d*m
2 楼
同一个职位转成EB3，那不就是说这个职位需要EB3就可以了，那以后如果EB2比EB3又快
了，你们公司以后的人还好办EB2了吗？
了，你们公司以后的人还好办EB2了吗？
s*a
3 楼
【 以下文字转载自 Returnee 讨论区 】
发信人: syria (syria), 信区: Returnee
标 题: 请问办理《留学回国人员证明》的毕业证复印件必须是公证过的吗？
发信站: BBS 未名空间站 (Fri Jul 2 02:55:17 2010, 美东)
直接复印一下毕业证不行吗？
发信人: syria (syria), 信区: Returnee
标 题: 请问办理《留学回国人员证明》的毕业证复印件必须是公证过的吗？
发信站: BBS 未名空间站 (Fri Jul 2 02:55:17 2010, 美东)
直接复印一下毕业证不行吗？
v*m
5 楼
http://www.bls.gov/opub/mlr/2015/article/stem-crisis-or-stem-su
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ARTICLE
MAY 2015
STEM crisis or STEM surplus? Yes and yes
The last decade has seen considerable concern regarding a shortage of
science, technology, engineering, and mathematics (STEM) workers to meet the
demands of the labor market. At the same time, many experts have presented
evidence of a STEM worker surplus. A comprehensive literature review, in
conjunction with employment statistics, newspaper articles, and our own
interviews with company recruiters, reveals a significant heterogeneity in
the STEM labor market: the academic sector is generally oversupplied, while
the government sector and private industry have shortages in specific areas.
Introduction
Economic projections point to a need for approximately 1 million more STEM
professionals than the U.S. will produce at the current rate over the next
decade if the country is to retain its historical preeminence in science and
technology.—President’s Council of Advisors on Science and Technology1
Unemployment rates within STEM elds…are often higher than they’ve been
in years—a sign that there is a shortage of jobs, not workers.—Michael
Anft2
Over the past decade, there has been substantial concern regarding the
adequacy of the science, technology, engineering, and math (STEM) workforce.
Opposing sides paint a polarizing picture: Is there a “STEM crisis” or a
“STEM surplus”? Our answer is that there are both.
STEM covers a diverse array of occupations, from mathematicians to
biomedical researchers, and at degree levels from bachelor to Ph.D. Some
occupations have a shortage of qualified talent, such as nuclear and
electrical engineering Ph.D.’s who are U.S.citizens; in other areas,
such as biology Ph.D.’s aiming to become professors, there is a surplus.
Although many studies have examined the science and engineering workforce in
the aggregate,3little analysis has been aimed at identifying specific
areas of STEM worker shortage or surplus. Using a “taxicab queuing model”
as a framing metaphor, this article examines the heterogeneous nature of
STEM occupations by studying distinct STEM disciplines and employment
sectors on the basis of current literature and statistical data, as well as
anecdotal evidence from newspapers.4To augment our findings, we
interviewed company recruiters from a wide range of industries in order to
gauge the ability of employers to fill open positions. We evaluate these
interviews by means of labor market data and scholarly work so as to
understand better, from a recruiter’s perspective, the hiring needs of
employers and the hiring difficulties encountered by STEM workers.
The ongoing STEM debate.Depending on the definition, the size of the
STEM workforce can range from 5 percent to 20 percent of all U.S. workers.
Although fields such as computer programming and mechanical engineering are
generally considered STEM fields, there is less consensus on areas such as
medicine, architecture, science education, social sciences, and blue-collar
manufacturing work. In this article, “STEM” refers to the science,
engineering, mathematics, and information technology domain detailed by the
Standard Occupation Classification Policy Committee, but excluding
managerial and sales occupations. Under this definition, postsecondary
teachers in STEM fields and lab technicians are considered STEM workers, but
workers in skilled trades, such as machinists, are not. Our analysis
focuses on graduates with postsecondary education within this STEM domain.
Numerous reports detail the growing concern of policymakers and industry
leaders regarding a shortage in the STEM workforce believed necessary to
sustain the U.S. innovation enterprise, global competitiveness, and national
security.5Most notable is the National Academies’ reportRising
Above the Gathering Storm, which called for improvements in kindergarten
through 12th-grade science and mathematics education and increasing the
attractiveness of higher education, among other recommendations.6The
report highlighted troubling issues in a number of areas: low STEM retention
rates, a relative decline in the number of U.S. citizens enrolled in
science and engineering graduate school, and lower percentages of STEM
graduates than those of other developed countries. These sentiments were
echoed in a 2012 report by the U.S. Congress Joint Economic Committee which
stated that the current STEM workforce was falling short of demand in both
STEM and non-STEM occupations.7According to the President’s Council of
Advisors on Science and Technology, the United States would need to increase
its yearly production of undergraduate STEM degrees by 34 percent over
current rates to match the demand forecast for STEM professionals.8
There are, however, many who hold a different view. For example, Michael S.
Teitelbaum, vice president of the Sloan Foundation, opined that there are no
general shortages of scientists and engineers.9He went even further, to
state that there is evidence suggesting surpluses: there are significantly
more science and engineering graduates in the United States than attractive
positions available in the workforce. Similarly, B. Lindsay Lowell and
Harold Salzman have pointed to the disproportionate percentage of bachelor’
s degree STEM holders not employed in STEM occupations.10
Looking at the STEM labor market, Salzman and colleagues concluded that, for
every two students graduating with a U.S. STEM degree, only one is employed
in STEM and that 32percent of computer science graduates not employed
in information technology attributed their situation to a lack of available
jobs.11In 2014, the U.S. Census Bureau reported that 74 percent of those
who have a bachelor’s degree in a STEM major are not employed in STEM
occupations.12
Taxicab queuing metaphor
The taxicab queuing problem was first documented in the literature by David
George Kendall.13According to the taxicab queuing metaphor, each taxi–
passenger system represents a narrow segment of the STEM employment system.
Employers or job positions can be thought of as a finite number of taxicabs,
and STEM workers can be thought of as a stream of would-be passengers. We
have employers searching for employees, analogous to a queue of taxis
waiting for passengers, and another queue of STEM workers searching for jobs
, similar to how passengers wait for taxis. If the number of employers
searching for employees is greater than the number of STEM workers, we have
a queue of taxis, which manifests itself in the real world as a STEM
shortage. If the number of STEM workers is greater than the number of
employers, we have a queue of STEM workers, meaning that there is a STEM
surplus. If the number of employers and the number of STEM workers are equal
, we have a momentary match between supply and demand and there is no queue.
This queuing theory framework provides a novel approach to looking at the
STEM labor market and the STEM crisis-versus-surplus conundrum. The demand
and supply of STEM workers vary by market and location in much the same way
that the demand and supply of taxicabs and passengers do. Just as there are
separate lines for taxicabs that accept credit cards versus ones that do not
, there are distinct lines for each type of STEM occupation. The demand for
workers with doctorates in mechanical engineering is different from the
demand for those with bachelor’s degrees in mechanical engineering, and the
supply of workers with doctorates in the biomedical sciences is different
from the supply of those with doctorates in physics. There are also spatial
differences. A queue of waiting taxis may be a common sight at an airport,
but outside a hotel it may be more common to see a queue of waiting
passengers. Analogously, the demand for petroleum engineers in Texas is
different from the demand for petroleum engineers in Massachusetts. The
upshot is that there may not be a STEM “crisis” in all job categories, but
instead just in select ones at certain degree levels and in certain
locations.
This model also captures the probabilistic nature of supply-and-demand
markets. The times at which both employers and STEM workers enter the job
market are uncertain. A job segment that traditionally has a shortage of
workers may at some times have a surplus and vice versa. Thus, it is
probably far more accurate to state that, within STEM job categories, there
is a “crisis” or a “surplus” depending on the circumstances at the time
the categories are investigated.
Methodology and data
The STEM supply-and-demand dynamics involve many actors: students, current
STEM workers, educational institutions, government, and the private sector.
Depending on the STEM segment, changes in each of the actors influence the
market to varying degrees. Detailed data on STEM labor markets tend to be
sparse. On the supply side, underreporting surpluses is a problem: the
reported unemployment rate of STEM graduates is consistently low, but does
not reflect those who are underemployed or have switched fields. On the
demand side, there is little available data on job openings in the aggregate
for various STEM job segments.
To analyze the STEM labor market, we used an indepth literature review of
available data sources in conjunction with other sources, such as newspaper
articles. To obtain firsthand data, we also interviewed talent recruiters
from a wide variety of organizations, including government contractors,
media companies, information technology companies, research institutes,
startups, and consulting agencies. Because of the small sample size (n=
18), the interviews may be limited in generalizability. Hence, interview
results are included only when they supplement the literature or fill gaps
in it. Our objective is to highlight the heterogeneity of the demand for and
supply of STEM workers, rather than paint a complete picture of supply and
demand across all STEM job segments.
Literature survey and results
As intimated from the outset, the literature on the supply and demand of
STEM workers is bipolar, with one side proclaiming an impending STEM crisis
and the other side asserting a STEM surplus. To understand this conundrum
better, we examine the STEM market at a deeper level. By segmenting the STEM
labor market into different disciplines, sectors, and skill levels, we find
that there is considerable heterogeneity in the supply and demand of
workers. Our analysis of the STEM labor market is broken down into three
main employment sectors—academia, government, and the private sector—and
then further narrowed down by specific job categories and disciplines.
Academia. The academic employment sector considered here comprises 2- and 4-
year colleges, universities, and university-affiliated research institutes.
STEM graduates at the bachelor’s level are typically employed as research
assistants, research associates, or technicians. Master’s-level graduates
are employed predominantly as research associates and staff scientists or,
at teaching institutions, as instructors or lecturers. The minimum
requirement for a tenure-track professor position is a Ph.D., with many
positions now even requiring one or more postdoctoral appointments (postdocs
). We found no literature proclaiming a shortage of STEM graduates in the
academic employment sector. On the contrary, numerous articles bemoan the
lack of permanent faculty positions—a state of affairs that forces young Ph
.D.’s to take low-paying temporary positions as postdocs and adjunct
faculty.
Many students enter doctoral programs with the intent of climbing the
academic ladder and obtaining tenure as a professor. But in many fields,
open positions are difficult to find. In fact, the intensified competition
for assistant professor openings has resulted in higher quality new hires,
meaning that there is a greatly increased chance of obtaining tenure. Then,
as the probability of achieving tenure increases, the number of new slots
will decline, further exacerbating the shortage of STEM faculty slots.
To examine the production of Ph.D.’s for the academic job market, we and a
colleague borrowed the concept ofR0, the basic reproduction number, and
applied it to academia.14For academia,R0was defined as the mean
number of new Ph.D.’s a typical tenure-track faculty member will graduate
during his or her academic career. WhenR0= 1.0, each professor, on
average, graduates one new Ph.D. that can replace him or her. WhenR0
> 1.0, the number of faculty slots has remained almost constant and there
are more workers with doctorates than there are faculty positions.
View Chart Data
Using this method, we estimateR0for all fields of study in the
United States. (We assume the average career duration to be 20 years.15
We use 2012–2013 data from the College and University Professional
Association for Human Resources (CUPA-HR), which reports the number of
tenured and tenure-track faculty at 794 institutions in the United States.16
We also use data from the National Center for Education Statistics’
Integrated Postsecondary Education Data System, which has the number of Ph.D
.’s awarded in 2012 at those same institutions. We group disciplines by
their Classification of Instructional Programs (CIP) code,17a taxonomic
scheme devised by the National Center for Education Statistics to track
fields of study. Figure 1 shows thatR0varies considerably across the
broad disciplines listed.
Although the number of Ph.D.’s has been climbing steadily, the number of
professor positions has remained almost constant in most fields, except for
the biomedical sciences and computer sciences.18A higherR0indicates
that more Ph.D.’s are competing for tenured and tenure-track faculty slots,
provided that the number of positions remains constant. For example,R0=
6.9 signifies that a tenure-track position is available for only 14 percent
(1 out of 6.9) of new Ph.D.’s in engineering. Our calculations show that
0
2R0> 1 for all STEM fields, indicating that there are more Ph.D.’s
eligible for academic positions than there are openings, assuming no growth
in the number of tenure-track faculty slots.
TheseR0statistics confirm anecdotal accounts. Faculty openings today
often attract hundreds of qualified applicants.19Henry Sauermann and
Michael Roach studied the preferences of science Ph.D. students (n= 4,
109) and found that the majority considered a faculty research career to be
an “extremely attractive” career path.20However, only a fortunate few
go directly from graduate school to a tenure-track faculty position. In 2010
, less than 15 percent of new Ph.D.’s in science, engineering, and health-
related fields found tenure-track positions within 3 years after graduation.
21For Ph.D.’s in the life sciences, the figure was an even smaller 7.6
percent. Most who want an academic career join academia as postdocs or
adjunct faculty, hoping to vie for a tenure-track faculty position in the
future.
Our findings here are consistent with many others in the literature. In 2007
, Michael S. Teitelbaum highlighted the poor prospects for recent doctorates
and postdocs.22Similarly, the RAND Corporation pointed out that the
length of postbaccalaureate study for the biosciences has increased
considerably, from between 7 and 8 years to between 9 and 12, and that many
are unable to secure stable employment with tenure until their late thirties
.23This finding was substantiated in a National Research Council report,
Bridges to Independence, which focused on the poor state of biomedical
research careers and urged immediate reform to enhance the quality of
training and to foster opportunities for young researchers to conduct
independent research.24Although this academic surplus began in the
biosciences, it has now extended to encompass many STEM fields, such as
astronomy, meteorology, and high-energy physics.25
Thus, in the academic employment sector, we find no evidence of any
shortages. To the contrary, it appears that the mismatch is between an
oversupply of Ph.D.’s desiring an academic career and the relative paucity
of tenure-track faculty positions.26Although the degree of mismatch
varies according to discipline, we have long queues of Ph.D.’s competing
for nearly all STEM-related faculty positions.
The government and government-related sector.For the purposes considered
here, this sector comprises different branches of civilian government
organizations that require their employees to hold U.S. citizenship and
certain security clearances. Examples are the U.S. Department of Energy’s
National Laboratories and the U.S. Department of Defense (DOD), the military
, and a number of defense and aerospace contractors and research institutes.
This section synthesizes reports produced by the National Academies that
studied the hiring needs of the U.S. Air Force and the DOD with anecdotal
accounts from the authors’ interviews.
The National Research Council Committee states that the Air Force had a
robust supply of personnel with STEM degrees to meet its recruiting goals
for STEM positions, with a few exceptions.27The Air Force Personnel
Center found staffing gaps in electrical engineering, operations research,
quantitative psychology, physics, nuclear engineering, and systems
engineering, specifically with regard to graduates with advanced degrees.
The Aeronautical Systems Center commander also identified shortages, in
areas such as electromagnetics, structures, software, reliability and
maintainability, and manufacturing engineering.
Similarly, the National Academy of Sciences Committee, charged with
identifying the needs of the U.S. DOD and the U.S. defense industrial base,
found that DOD representatives almost unanimously stated that there was no
STEM workforce crisis, but that there were specific areas in which needs
were not being met.28For example, 800 funded positions were open for 90
days or more for systems engineers and other STEM workers, and there were
opportunities for cybersecurity and intelligence professionals as well. In
addition, the aerospace and defense industry has experienced difficulty in
hiring mechanical engineers, systems engineers, and aerospace engineers.
These sentiments were generally echoed in our interviews. One participant, a
recruiting manager for a government research institute, said that hiring at
the bachelor’s level was relatively easy, but hiring those with advanced
degrees was proving more challenging because of skill set mismatches.29
He stated that, although there were many applicants from the mechanical,
aeronautical, and bioengineering disciplines, shortages of electrical
engineers existed at the doctoral level. Software development skills at all
degree levels were also in high demand.
Another recruiting manager for a government research institute found
difficulties hiring those with advanced degrees in computer sciences and
computer engineering.30Because of budget stipulations, salaries his
institute offered could not compete with those in the private sector.
Although foreign nationals can generally be brought in to bridge skill gaps
in academia and the private sector, that is currently not an option in many
areas for government workers and contractors, including defense-related
contractors. The International Traffic in Arms Regulations dictate that
information and material related to defense and military technologies may be
shared only with U.S. citizens unless a specific exemption is obtained. A
manager for a large government contractor found substantial shortages in
hiring of Ph.D.’s in fields such as nuclear engineering, materials science,
and thermohydraulic engineering.31This contractor requires only a dozen or
so workers in each field, but the supply of U.S. citizens with doctorates in
these fields is small.
A recruiter seeking people to work in engineering startup companies told us
of problems finding materials science Ph.D.’s who were U.S. citizens.32
Although the recruiter received dozens of applications from qualified
foreign nationals, the government funding involved required U.S. citizenship.
In the government and government-related employment sector, we found no
evidence of widespread STEM shortages; however, there may be shortages at
the advanced-degree level due to citizenship and security clearance
requirements.
Private sector.Much of the literature on the STEM crisis emanates from
concerns about shortages or surpluses in the private-sector STEM labor
market; however, the crisis is generally discussed in broad terms,
referencing the STEM workforce as a whole. For example, the report by the
President’s Council of Advisors on Science and Technology called for an
additional 1 million STEM degrees over the next decade.33Similarly, many
studies dispute the claim that there are STEM shortages at the aggregate
level and point to shortages only in specific fields.34However, the
disciplines involved and the degree levels at which graduates are actually
in demand are unclear.
The findings that follow are from a literature review and interviews.
1. Shortages.There are many accounts based on anecdotal evidence that
break down disciplines to a relatively detailed level and identify specific
areas with a shortage of STEM talent. For example, Lou Frenzel identified
shortages among analog/linear and radiofrequency/microwave design engineers
and skilled programmers.35Similarly, Jonathan Rothwell analyzed the
Conference Board’s Help-Wanted Online Seriesand found that in 2010
there were seven job openings in computer occupations for every graduate
with a relevant computer major.36And Abby Lombardi, inWanted Analytics,
which aggregates job listings from all over the World Wide Web, reported in
2013 that help-wanted ads for software developers were up 120percent
over the previous year.37
From our interviews with recruiters, we also find software development
skills to be the most in demand. Experienced mobile application developers
are especially coveted.38In certain cases, it does not even matter
whether a candidate has a bachelor’s degree in a specific area: companies39
are looking for candidates with hands-on experience in software
development through “hack-a-thons,” extracurricular projects, and
internships. These anecdotal accounts are supported by a falling
unemployment rate for software developers, from 4percent in 2011 to 2.8
percent in 2012 and down to 2.2percent in the first quarter of 2013.
40Also, the recent “big data” trend has sparked demand for data
scientists in all areas, from health care to retail.41
Because energy prices surged in the last decade and new technologies for the
domestic extraction of oil and gas emerged, petroleum engineers are now in
high demand, even though that occupation was an unattractive and declining
one throughout the 1980s and 1990s.42As an indicator, the real wages of
petroleum engineers have increased.43
Demand for STEM skills also exists below the bachelor’s level. A 2011
survey of manufacturers found that as many as 600,000 jobs remain unfilled
because there is a lack of qualified candidates for technical positions
requiring STEM skills—primarily production positions (e.g., machinists,
operators, craftworkers, distributors, and technicians).44Some are
concerned that very few people are pursuing employment in the skilled trades
.45
2. Surpluses.At the same time that shortages exist, there are areas with
surpluses of STEM talent—most notably, biomedical Ph.D.’s. An NIH blue-
ribbon panel found an increasing number of biomedical Ph.D.’s working in
science-related occupations that do not involve research and even that do
not require graduate training in science.46Chemistry and biomedical
graduates also have taken a hard hit, due to the downsizing and offshoring
of biotechnology, chemical, and pharmaceutical jobs.47Since 2000, U.S.
pharmaceutical companies have cut 300,000 jobs.48By 2012, downsizing had
increased the unemployment rate among chemists to 4.6percent, the
highest in 40 years. One recruiter we interviewed said he found that many
chemical engineering college graduates were seeking employment in software
development.49Among young Ph.D.’s, the situation was even worse: just
38percent of newly minted chemistry Ph.D.’s were employed in full-time,
nonpostdoc positions in 2011, down from 51percent in 2008.50New
chemical engineering Ph.D.’s fared better, with a full-time, nonpostdoc
employment rate of 61percent.
In 2010 and 2011, the unemployment rate for electrical engineers held at 3.4
percent, but it spiked to 6.5percent in the first quarter of 2013.
Although recruiters in the government and government contractor sector had
concerns about hiring electrical engineers, these concerns did not surface
in our interviews with private sector recruiters, suggesting that the hiring
challenge in the government sector is probably due to the U.S. citizenship
requirement.
View Chart Data
Because the unemployment rate for STEM Ph.D.’s is generally low, a more
useful indicator of job market strength is the number of STEM Ph.D.’s who
accept potentially permanent positions, compared with those who accept
postdocs. A considerable number of physics Ph.D.’s are unemployed,
accepting postdocs and other temporary positions (69 percent in 2010, as
opposed to 51 percent before the dot-com bust), indicating that the demand
for physics Ph.D.’s is not high. (See figure 2.)
View Chart Data
3. Geographic differences.There are also regional differences in the
labor markets for STEM workers. For example, software developers are in much
higher demand in California, Washington State, and New York, a fact that is
reflected in their higher wages in those states. (See figure 3.) This trend
is seen across different STEM occupations, and areas of demand vary.
Petroleum engineers, for instance, are clustered in Texas and Oklahoma. A
recruiter for a company in Connecticut stated that one of the primary
challenges he faced in hiring software developers was the location of the
office, because many qualified candidates were reluctant to relocate to
Connecticut.51Another recruiter mentioned that his company relocated to
the Boston area specifically to gain access to the local talent pool, a move
that improved recruitment.52
Summary
Across all the different disciplines, yes, there is a STEM crisis, and no,
there is no STEM crisis. It depends on how and where you look.
For most Ph.D.’s, the United States has a surplus of workers, especially in
tenure-track positions in academia. The exceptions are certain fields
within industry, such as petroleum engineering, process engineering, and
computer engineering, and other fields in the government sector, such as
nuclear engineering, materials science, and thermohydraulic engineering.
Academia tends to absorb the Ph.D.’s who are unable to find positions in
industry into postdoc positions. At the bachelor’s and master’s levels,
there is consistent demand for employees in software development, as well as
in high-growth areas such as mobile application development, data science,
and petroleum engineering. There is also demand below the bachelor’s level
in the manufacturing industry, which needs workers in the skilled trades,
such as machinists and technicians. Hence, we have aheterogeneousmixture
of supply and demand for different occupations: some have a queue of
workers, others a queue of unfilled positions.
Our findings are supported by the National Center for Education Statistics’
longitudinal study of baccalaureate holders, a survey which found that 69.7
% of graduates who had not enrolled in advanced-degree studies after they
completed their bachelor’s degrees in the 2007–2008 academic year were
employed in a full-time job with an annualized median salary of $46,000
between graduation and 2012.53For STEM majors, the full-time employment
rate increased to 77.2percent and the median salary was $60,000. However
, not all STEM majors were equally in demand: computer and information
sciences majors and engineering and engineering technology majors had full-
time employment rates of 77.1 percent and 83.2 percent, respectively, and
corresponding median salaries of $66,000 and $67,000, while graduates who
majored in the biological and physical sciences, science technology,
mathematics, or agricultural sciences had a full-time employment rate of 71.
4% with a median salary of $46,800, closer to that of non-STEM majors. These
data are consistent with our conclusion that there is significant variation
in the demand for graduates, depending on the STEM discipline.
Conclusion
This article draws upon a variety of data sources—professional science and
engineering societies, labor market data, the National Science Foundation,
literature reviews, and anecdotal accounts—to understand the supply-and-
demand landscape for the STEM labor market. The analysis presented offers a
first cut at identifying disciplines and degree levels that are either in
demand or oversupplied. A clearer picture of the supply and demand of the
STEM workforce will require better data and consistent monitoring of both
employer requirements and STEM worker availability.
We introduced the taxicab queuing model as a metaphor for the STEM labor
market. Depending on the STEM job segment, we can either have a queue of
positions waiting to be filled (cf. taxis) or a queue of STEM workers
waiting for jobs (cf. passengers). The characteristics of the queue depend
on different factors: the rate of job turnover (cf. taxi service rate); the
STEM worker arrival rate (cf. passenger arrival rate); the number of
positions available (cf. the number of taxis in the fleet); the location of
the job; the degree held by the worker (cf. type of taxi); and the worker’s
citizenship status. The model also highlights the probabilistic nature of
the supply-and-demand market: random fluctuations can cause job segments
that traditionally have a shortage of workers to have a surplus, and vice
versa. Although we currently lack the data to operationalize the model, it
presents a novel approach to characterizing the variation across STEM job
segments.
Our central question is whether there is a “STEM crisis” or a “STEM
surplus.” The answer is that both exist. Our analysis yields the following
findings:
The STEM labor market is heterogeneous. There are both shortages and
surpluses of STEM workers, depending on the particular job market segment.In
the academic job market, there is no noticeable shortage in any discipline.
In fact, there are signs of an oversupply of Ph.D.’s vying for tenure-
track faculty positions in many disciplines (e.g., biomedical sciences,
physical sciences).In the government and government-related job sector,
certain STEM disciplines have a shortage of positions at the Ph.D. level (e.
g., materials science engineering, nuclear engineering) and in general (e.g.
, systems engineers, cybersecurity, and intelligence professionals) due to
the U.S. citizenship requirement. In contrast, an oversupply of biomedical
engineers is seen at the Ph.D. level, and there are transient shortages of
electrical engineers and mechanical engineers at advanced-degree levels.In
the private sector, software developers, petroleum engineers, data
scientists, and those in skilled trades are in high demand; there is an
abundant supply of biomedical, chemistry, and physics Ph.D.’s; and
transient shortages and surpluses of electrical engineers occur from time to
time.The geographic location of the position affects hiring ease or
difficulty.
As our society relies further on technology for economic development and
prosperity, the vitality of the STEM workforce will continue to be a cause
for concern.
ACKNOWLEDGMENTS: Work on this project was supported by the National
Institutes of Health (NIH) under a grant titled “Developing a Scientific
Workforce Analysis and Modeling Framework (SWAM),” awarded to The Ohio
State University and the Massachusetts Institute of Technology (MIT), Center
for Engineering Systems Fundamentals (CESF)—NIH Grant # 5 U01 GM094141-02.
The discussion and conclusions presented are those of the authors and do
not necessarily represent the views of the NIH, The Ohio State University,
or MIT. We thank Joshua Hawley of The Ohio State University and Navid
Ghaffarzadegan of Virginia Tech for helpful comments on an earlier draft.
Notes
1President’s Council of Advisors on Science and Technology,Engage
to excel: producing one million additional college graduates with degrees in
science, technology, engineering, and mathematics(Executive Office of
the President of the United States, 2012).
2Michael Anft, “The STEM crisis: reality or myth?”The Chronicle of
Higher Education(November 11, 2013).
3B. Lindsay Lowell and Harold Salzman,Into the eye of the storm:
assessing the evidence on science and engineering education, quality, and
workforce demand(Washington, DC: Urban Institute, October 29, 2007);
Anthony P. Carnevale, Nicole Smith, and Michelle Melton,STEM: science,
technology, engineering, mathematics(Washington, DC: Georgetown
University Center on Education and the Workforce, 2011); and Terrence K.
Kelly, William P. Butz, Stephen Carroll, David M. Adamson, and Gabrielle
Bloom, eds.,The U.S. scientific and technical workforce(Santa Monica
, CA, Arlington, VA, and Pittsburgh, PA: RAND Corporation, June 2004).
4The taxicab queue is a classic queuing theory problem that models the
queues for taxis and passengers as a function of the arrival rates of
passengers and taxis and the size of the taxi fleet. The arrival rate of
passengers is modeled as a Poisson process, and the arrival time for a taxi
is modeled as a conditional Poisson process which depends on the number of
taxis that are currently busy. Numerical and graphical results of the
taxicab queuing model can be found in Yi Xue, “STEM Crisis or STEM Surplus?
” master’s thesis, Technology and Policy Program (Cambridge, MA:
Massachusetts Institute of Technology, 2014).
5Tapping America’s potential: the Education for Innovation Initiative(
Washington, DC, Business Roundtable, 2005);Ensuring a strong U.S.
scientific, technical, and engineering workforce in the 21st century(
Washington, DC: National Science and Technology Council, April 2000);The
science and engineering workforce: realizing America’s potential(Arlington,
VA: National Science Board, 2003).
6National Academy of Sciences, National Academy of Engineering, and
Institute of Medicine,Rising above the gathering storm: energizing and
employing America for a brighter economic future(Washington, DC: The
National Academies Press, 2007), pp. 1–591.
7Senator Bob Casey,STEM education: preparing for the jobs of the
future(Washington, DC: U.S. Congress Joint Economic Committee, April 2012).
8Engage to excel.
9“Testimony of Michael S. Teitelbaum before the Subcommittee on
Technology and Innovation,” November 6, 2007; see transcript,https://
science.house.gov/sites/republicans.science.house.gov/files/documents/
hearings/110607_teitelbaum.pdf.
10Lowell and Salzman,Into the eye of the storm.
11Hal Salzman, Daniel Kuehn, and B. Lindsay Lowell,Guestworkers in
the high-skill U.S. labor market: an analysis of supply, employment and wage
trends, EPI Briefing Paper no. 359 (Washington, DC: Economic Policy
Institute, April 24, 2013), pp. 1–35.
12Newsroom: Census Bureau reports majority of STEM college graduates do
not work in STEM occupations(U.S. Census Bureau, 2014). The U.S. Census
Bureau includes sales and managerial occupations, as well as social science
occupations, in its definition of STEM occupations.
13David George Kendall, “Some problems in the theory of queues,”
Journal of the Royal Statistical Society, Series B, vol. 13, no. 2, 1951, pp
. 151–185,http://www.jstor.org/stable/2984059?origin=JSTOR-pdf.
14Richard C. Larson, Navid Ghaffarzadegan, and Yi Xue, “Too many PhD
graduates or too few academic job openings: the basic reproductive number
0
2R0in academia,”Systems Research and Behavioral Science,
November/
December 2014, pp. 745–750.
15See Richard C. Larson and Mauricio Gómez Díaz, “Nonfixed retirement
age for university professors: modeling its effects on new faculty hires,”
Service Science, March 2012, pp. 69–78.
16Although only 294 of the 794 institutions have doctoral programs, the
number of faculty used in the calculation ofR0is the total for all
of those institutions, because the positions referred to are still tenured
and tenure-track faculty positions.
17Disciplines were included only if there were data available for both
the number of Ph.D.’s and the number of faculty.
18National Science Board,Science and engineering indicators 2014(
Arlington, VA: National Science Foundation, 2014).
19Beryl Lieff Benderley, “The real science gap,”Pacific Standard,
June 14, 2010,http://www.psmag.com/science/the-real-science-gap-16191.
20Henry Sauermann and Michael Roach, “Science PhD career preferences:
levels, changes, and advisor encouragement,”PLOS One, May 2, 2012,http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0036307.
21National Science Board,Science and engineering indicators 2014.
22Michael S. Teitelbaum,The current model of STEM graduate education
and postdocs: is it evolving to meet needs of the nation and its
participants?paper presented at the National Institutes of Health,
Washington, DC, November 5–6, 2007,http://rbm.nih.gov/stem/Teitelbaum.pdf.
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ARTICLE
MAY 2015
STEM crisis or STEM surplus? Yes and yes
The last decade has seen considerable concern regarding a shortage of
science, technology, engineering, and mathematics (STEM) workers to meet the
demands of the labor market. At the same time, many experts have presented
evidence of a STEM worker surplus. A comprehensive literature review, in
conjunction with employment statistics, newspaper articles, and our own
interviews with company recruiters, reveals a significant heterogeneity in
the STEM labor market: the academic sector is generally oversupplied, while
the government sector and private industry have shortages in specific areas.
Introduction
Economic projections point to a need for approximately 1 million more STEM
professionals than the U.S. will produce at the current rate over the next
decade if the country is to retain its historical preeminence in science and
technology.—President’s Council of Advisors on Science and Technology1
Unemployment rates within STEM elds…are often higher than they’ve been
in years—a sign that there is a shortage of jobs, not workers.—Michael
Anft2
Over the past decade, there has been substantial concern regarding the
adequacy of the science, technology, engineering, and math (STEM) workforce.
Opposing sides paint a polarizing picture: Is there a “STEM crisis” or a
“STEM surplus”? Our answer is that there are both.
STEM covers a diverse array of occupations, from mathematicians to
biomedical researchers, and at degree levels from bachelor to Ph.D. Some
occupations have a shortage of qualified talent, such as nuclear and
electrical engineering Ph.D.’s who are U.S.citizens; in other areas,
such as biology Ph.D.’s aiming to become professors, there is a surplus.
Although many studies have examined the science and engineering workforce in
the aggregate,3little analysis has been aimed at identifying specific
areas of STEM worker shortage or surplus. Using a “taxicab queuing model”
as a framing metaphor, this article examines the heterogeneous nature of
STEM occupations by studying distinct STEM disciplines and employment
sectors on the basis of current literature and statistical data, as well as
anecdotal evidence from newspapers.4To augment our findings, we
interviewed company recruiters from a wide range of industries in order to
gauge the ability of employers to fill open positions. We evaluate these
interviews by means of labor market data and scholarly work so as to
understand better, from a recruiter’s perspective, the hiring needs of
employers and the hiring difficulties encountered by STEM workers.
The ongoing STEM debate.Depending on the definition, the size of the
STEM workforce can range from 5 percent to 20 percent of all U.S. workers.
Although fields such as computer programming and mechanical engineering are
generally considered STEM fields, there is less consensus on areas such as
medicine, architecture, science education, social sciences, and blue-collar
manufacturing work. In this article, “STEM” refers to the science,
engineering, mathematics, and information technology domain detailed by the
Standard Occupation Classification Policy Committee, but excluding
managerial and sales occupations. Under this definition, postsecondary
teachers in STEM fields and lab technicians are considered STEM workers, but
workers in skilled trades, such as machinists, are not. Our analysis
focuses on graduates with postsecondary education within this STEM domain.
Numerous reports detail the growing concern of policymakers and industry
leaders regarding a shortage in the STEM workforce believed necessary to
sustain the U.S. innovation enterprise, global competitiveness, and national
security.5Most notable is the National Academies’ reportRising
Above the Gathering Storm, which called for improvements in kindergarten
through 12th-grade science and mathematics education and increasing the
attractiveness of higher education, among other recommendations.6The
report highlighted troubling issues in a number of areas: low STEM retention
rates, a relative decline in the number of U.S. citizens enrolled in
science and engineering graduate school, and lower percentages of STEM
graduates than those of other developed countries. These sentiments were
echoed in a 2012 report by the U.S. Congress Joint Economic Committee which
stated that the current STEM workforce was falling short of demand in both
STEM and non-STEM occupations.7According to the President’s Council of
Advisors on Science and Technology, the United States would need to increase
its yearly production of undergraduate STEM degrees by 34 percent over
current rates to match the demand forecast for STEM professionals.8
There are, however, many who hold a different view. For example, Michael S.
Teitelbaum, vice president of the Sloan Foundation, opined that there are no
general shortages of scientists and engineers.9He went even further, to
state that there is evidence suggesting surpluses: there are significantly
more science and engineering graduates in the United States than attractive
positions available in the workforce. Similarly, B. Lindsay Lowell and
Harold Salzman have pointed to the disproportionate percentage of bachelor’
s degree STEM holders not employed in STEM occupations.10
Looking at the STEM labor market, Salzman and colleagues concluded that, for
every two students graduating with a U.S. STEM degree, only one is employed
in STEM and that 32percent of computer science graduates not employed
in information technology attributed their situation to a lack of available
jobs.11In 2014, the U.S. Census Bureau reported that 74 percent of those
who have a bachelor’s degree in a STEM major are not employed in STEM
occupations.12
Taxicab queuing metaphor
The taxicab queuing problem was first documented in the literature by David
George Kendall.13According to the taxicab queuing metaphor, each taxi–
passenger system represents a narrow segment of the STEM employment system.
Employers or job positions can be thought of as a finite number of taxicabs,
and STEM workers can be thought of as a stream of would-be passengers. We
have employers searching for employees, analogous to a queue of taxis
waiting for passengers, and another queue of STEM workers searching for jobs
, similar to how passengers wait for taxis. If the number of employers
searching for employees is greater than the number of STEM workers, we have
a queue of taxis, which manifests itself in the real world as a STEM
shortage. If the number of STEM workers is greater than the number of
employers, we have a queue of STEM workers, meaning that there is a STEM
surplus. If the number of employers and the number of STEM workers are equal
, we have a momentary match between supply and demand and there is no queue.
This queuing theory framework provides a novel approach to looking at the
STEM labor market and the STEM crisis-versus-surplus conundrum. The demand
and supply of STEM workers vary by market and location in much the same way
that the demand and supply of taxicabs and passengers do. Just as there are
separate lines for taxicabs that accept credit cards versus ones that do not
, there are distinct lines for each type of STEM occupation. The demand for
workers with doctorates in mechanical engineering is different from the
demand for those with bachelor’s degrees in mechanical engineering, and the
supply of workers with doctorates in the biomedical sciences is different
from the supply of those with doctorates in physics. There are also spatial
differences. A queue of waiting taxis may be a common sight at an airport,
but outside a hotel it may be more common to see a queue of waiting
passengers. Analogously, the demand for petroleum engineers in Texas is
different from the demand for petroleum engineers in Massachusetts. The
upshot is that there may not be a STEM “crisis” in all job categories, but
instead just in select ones at certain degree levels and in certain
locations.
This model also captures the probabilistic nature of supply-and-demand
markets. The times at which both employers and STEM workers enter the job
market are uncertain. A job segment that traditionally has a shortage of
workers may at some times have a surplus and vice versa. Thus, it is
probably far more accurate to state that, within STEM job categories, there
is a “crisis” or a “surplus” depending on the circumstances at the time
the categories are investigated.
Methodology and data
The STEM supply-and-demand dynamics involve many actors: students, current
STEM workers, educational institutions, government, and the private sector.
Depending on the STEM segment, changes in each of the actors influence the
market to varying degrees. Detailed data on STEM labor markets tend to be
sparse. On the supply side, underreporting surpluses is a problem: the
reported unemployment rate of STEM graduates is consistently low, but does
not reflect those who are underemployed or have switched fields. On the
demand side, there is little available data on job openings in the aggregate
for various STEM job segments.
To analyze the STEM labor market, we used an indepth literature review of
available data sources in conjunction with other sources, such as newspaper
articles. To obtain firsthand data, we also interviewed talent recruiters
from a wide variety of organizations, including government contractors,
media companies, information technology companies, research institutes,
startups, and consulting agencies. Because of the small sample size (n=
18), the interviews may be limited in generalizability. Hence, interview
results are included only when they supplement the literature or fill gaps
in it. Our objective is to highlight the heterogeneity of the demand for and
supply of STEM workers, rather than paint a complete picture of supply and
demand across all STEM job segments.
Literature survey and results
As intimated from the outset, the literature on the supply and demand of
STEM workers is bipolar, with one side proclaiming an impending STEM crisis
and the other side asserting a STEM surplus. To understand this conundrum
better, we examine the STEM market at a deeper level. By segmenting the STEM
labor market into different disciplines, sectors, and skill levels, we find
that there is considerable heterogeneity in the supply and demand of
workers. Our analysis of the STEM labor market is broken down into three
main employment sectors—academia, government, and the private sector—and
then further narrowed down by specific job categories and disciplines.
Academia. The academic employment sector considered here comprises 2- and 4-
year colleges, universities, and university-affiliated research institutes.
STEM graduates at the bachelor’s level are typically employed as research
assistants, research associates, or technicians. Master’s-level graduates
are employed predominantly as research associates and staff scientists or,
at teaching institutions, as instructors or lecturers. The minimum
requirement for a tenure-track professor position is a Ph.D., with many
positions now even requiring one or more postdoctoral appointments (postdocs
). We found no literature proclaiming a shortage of STEM graduates in the
academic employment sector. On the contrary, numerous articles bemoan the
lack of permanent faculty positions—a state of affairs that forces young Ph
.D.’s to take low-paying temporary positions as postdocs and adjunct
faculty.
Many students enter doctoral programs with the intent of climbing the
academic ladder and obtaining tenure as a professor. But in many fields,
open positions are difficult to find. In fact, the intensified competition
for assistant professor openings has resulted in higher quality new hires,
meaning that there is a greatly increased chance of obtaining tenure. Then,
as the probability of achieving tenure increases, the number of new slots
will decline, further exacerbating the shortage of STEM faculty slots.
To examine the production of Ph.D.’s for the academic job market, we and a
colleague borrowed the concept ofR0, the basic reproduction number, and
applied it to academia.14For academia,R0was defined as the mean
number of new Ph.D.’s a typical tenure-track faculty member will graduate
during his or her academic career. WhenR0= 1.0, each professor, on
average, graduates one new Ph.D. that can replace him or her. WhenR0
> 1.0, the number of faculty slots has remained almost constant and there
are more workers with doctorates than there are faculty positions.
View Chart Data
Using this method, we estimateR0for all fields of study in the
United States. (We assume the average career duration to be 20 years.15
We use 2012–2013 data from the College and University Professional
Association for Human Resources (CUPA-HR), which reports the number of
tenured and tenure-track faculty at 794 institutions in the United States.16
We also use data from the National Center for Education Statistics’
Integrated Postsecondary Education Data System, which has the number of Ph.D
.’s awarded in 2012 at those same institutions. We group disciplines by
their Classification of Instructional Programs (CIP) code,17a taxonomic
scheme devised by the National Center for Education Statistics to track
fields of study. Figure 1 shows thatR0varies considerably across the
broad disciplines listed.
Although the number of Ph.D.’s has been climbing steadily, the number of
professor positions has remained almost constant in most fields, except for
the biomedical sciences and computer sciences.18A higherR0indicates
that more Ph.D.’s are competing for tenured and tenure-track faculty slots,
provided that the number of positions remains constant. For example,R0=
6.9 signifies that a tenure-track position is available for only 14 percent
(1 out of 6.9) of new Ph.D.’s in engineering. Our calculations show that
0
2R0> 1 for all STEM fields, indicating that there are more Ph.D.’s
eligible for academic positions than there are openings, assuming no growth
in the number of tenure-track faculty slots.
TheseR0statistics confirm anecdotal accounts. Faculty openings today
often attract hundreds of qualified applicants.19Henry Sauermann and
Michael Roach studied the preferences of science Ph.D. students (n= 4,
109) and found that the majority considered a faculty research career to be
an “extremely attractive” career path.20However, only a fortunate few
go directly from graduate school to a tenure-track faculty position. In 2010
, less than 15 percent of new Ph.D.’s in science, engineering, and health-
related fields found tenure-track positions within 3 years after graduation.
21For Ph.D.’s in the life sciences, the figure was an even smaller 7.6
percent. Most who want an academic career join academia as postdocs or
adjunct faculty, hoping to vie for a tenure-track faculty position in the
future.
Our findings here are consistent with many others in the literature. In 2007
, Michael S. Teitelbaum highlighted the poor prospects for recent doctorates
and postdocs.22Similarly, the RAND Corporation pointed out that the
length of postbaccalaureate study for the biosciences has increased
considerably, from between 7 and 8 years to between 9 and 12, and that many
are unable to secure stable employment with tenure until their late thirties
.23This finding was substantiated in a National Research Council report,
Bridges to Independence, which focused on the poor state of biomedical
research careers and urged immediate reform to enhance the quality of
training and to foster opportunities for young researchers to conduct
independent research.24Although this academic surplus began in the
biosciences, it has now extended to encompass many STEM fields, such as
astronomy, meteorology, and high-energy physics.25
Thus, in the academic employment sector, we find no evidence of any
shortages. To the contrary, it appears that the mismatch is between an
oversupply of Ph.D.’s desiring an academic career and the relative paucity
of tenure-track faculty positions.26Although the degree of mismatch
varies according to discipline, we have long queues of Ph.D.’s competing
for nearly all STEM-related faculty positions.
The government and government-related sector.For the purposes considered
here, this sector comprises different branches of civilian government
organizations that require their employees to hold U.S. citizenship and
certain security clearances. Examples are the U.S. Department of Energy’s
National Laboratories and the U.S. Department of Defense (DOD), the military
, and a number of defense and aerospace contractors and research institutes.
This section synthesizes reports produced by the National Academies that
studied the hiring needs of the U.S. Air Force and the DOD with anecdotal
accounts from the authors’ interviews.
The National Research Council Committee states that the Air Force had a
robust supply of personnel with STEM degrees to meet its recruiting goals
for STEM positions, with a few exceptions.27The Air Force Personnel
Center found staffing gaps in electrical engineering, operations research,
quantitative psychology, physics, nuclear engineering, and systems
engineering, specifically with regard to graduates with advanced degrees.
The Aeronautical Systems Center commander also identified shortages, in
areas such as electromagnetics, structures, software, reliability and
maintainability, and manufacturing engineering.
Similarly, the National Academy of Sciences Committee, charged with
identifying the needs of the U.S. DOD and the U.S. defense industrial base,
found that DOD representatives almost unanimously stated that there was no
STEM workforce crisis, but that there were specific areas in which needs
were not being met.28For example, 800 funded positions were open for 90
days or more for systems engineers and other STEM workers, and there were
opportunities for cybersecurity and intelligence professionals as well. In
addition, the aerospace and defense industry has experienced difficulty in
hiring mechanical engineers, systems engineers, and aerospace engineers.
These sentiments were generally echoed in our interviews. One participant, a
recruiting manager for a government research institute, said that hiring at
the bachelor’s level was relatively easy, but hiring those with advanced
degrees was proving more challenging because of skill set mismatches.29
He stated that, although there were many applicants from the mechanical,
aeronautical, and bioengineering disciplines, shortages of electrical
engineers existed at the doctoral level. Software development skills at all
degree levels were also in high demand.
Another recruiting manager for a government research institute found
difficulties hiring those with advanced degrees in computer sciences and
computer engineering.30Because of budget stipulations, salaries his
institute offered could not compete with those in the private sector.
Although foreign nationals can generally be brought in to bridge skill gaps
in academia and the private sector, that is currently not an option in many
areas for government workers and contractors, including defense-related
contractors. The International Traffic in Arms Regulations dictate that
information and material related to defense and military technologies may be
shared only with U.S. citizens unless a specific exemption is obtained. A
manager for a large government contractor found substantial shortages in
hiring of Ph.D.’s in fields such as nuclear engineering, materials science,
and thermohydraulic engineering.31This contractor requires only a dozen or
so workers in each field, but the supply of U.S. citizens with doctorates in
these fields is small.
A recruiter seeking people to work in engineering startup companies told us
of problems finding materials science Ph.D.’s who were U.S. citizens.32
Although the recruiter received dozens of applications from qualified
foreign nationals, the government funding involved required U.S. citizenship.
In the government and government-related employment sector, we found no
evidence of widespread STEM shortages; however, there may be shortages at
the advanced-degree level due to citizenship and security clearance
requirements.
Private sector.Much of the literature on the STEM crisis emanates from
concerns about shortages or surpluses in the private-sector STEM labor
market; however, the crisis is generally discussed in broad terms,
referencing the STEM workforce as a whole. For example, the report by the
President’s Council of Advisors on Science and Technology called for an
additional 1 million STEM degrees over the next decade.33Similarly, many
studies dispute the claim that there are STEM shortages at the aggregate
level and point to shortages only in specific fields.34However, the
disciplines involved and the degree levels at which graduates are actually
in demand are unclear.
The findings that follow are from a literature review and interviews.
1. Shortages.There are many accounts based on anecdotal evidence that
break down disciplines to a relatively detailed level and identify specific
areas with a shortage of STEM talent. For example, Lou Frenzel identified
shortages among analog/linear and radiofrequency/microwave design engineers
and skilled programmers.35Similarly, Jonathan Rothwell analyzed the
Conference Board’s Help-Wanted Online Seriesand found that in 2010
there were seven job openings in computer occupations for every graduate
with a relevant computer major.36And Abby Lombardi, inWanted Analytics,
which aggregates job listings from all over the World Wide Web, reported in
2013 that help-wanted ads for software developers were up 120percent
over the previous year.37
From our interviews with recruiters, we also find software development
skills to be the most in demand. Experienced mobile application developers
are especially coveted.38In certain cases, it does not even matter
whether a candidate has a bachelor’s degree in a specific area: companies39
are looking for candidates with hands-on experience in software
development through “hack-a-thons,” extracurricular projects, and
internships. These anecdotal accounts are supported by a falling
unemployment rate for software developers, from 4percent in 2011 to 2.8
percent in 2012 and down to 2.2percent in the first quarter of 2013.
40Also, the recent “big data” trend has sparked demand for data
scientists in all areas, from health care to retail.41
Because energy prices surged in the last decade and new technologies for the
domestic extraction of oil and gas emerged, petroleum engineers are now in
high demand, even though that occupation was an unattractive and declining
one throughout the 1980s and 1990s.42As an indicator, the real wages of
petroleum engineers have increased.43
Demand for STEM skills also exists below the bachelor’s level. A 2011
survey of manufacturers found that as many as 600,000 jobs remain unfilled
because there is a lack of qualified candidates for technical positions
requiring STEM skills—primarily production positions (e.g., machinists,
operators, craftworkers, distributors, and technicians).44Some are
concerned that very few people are pursuing employment in the skilled trades
.45
2. Surpluses.At the same time that shortages exist, there are areas with
surpluses of STEM talent—most notably, biomedical Ph.D.’s. An NIH blue-
ribbon panel found an increasing number of biomedical Ph.D.’s working in
science-related occupations that do not involve research and even that do
not require graduate training in science.46Chemistry and biomedical
graduates also have taken a hard hit, due to the downsizing and offshoring
of biotechnology, chemical, and pharmaceutical jobs.47Since 2000, U.S.
pharmaceutical companies have cut 300,000 jobs.48By 2012, downsizing had
increased the unemployment rate among chemists to 4.6percent, the
highest in 40 years. One recruiter we interviewed said he found that many
chemical engineering college graduates were seeking employment in software
development.49Among young Ph.D.’s, the situation was even worse: just
38percent of newly minted chemistry Ph.D.’s were employed in full-time,
nonpostdoc positions in 2011, down from 51percent in 2008.50New
chemical engineering Ph.D.’s fared better, with a full-time, nonpostdoc
employment rate of 61percent.
In 2010 and 2011, the unemployment rate for electrical engineers held at 3.4
percent, but it spiked to 6.5percent in the first quarter of 2013.
Although recruiters in the government and government contractor sector had
concerns about hiring electrical engineers, these concerns did not surface
in our interviews with private sector recruiters, suggesting that the hiring
challenge in the government sector is probably due to the U.S. citizenship
requirement.
View Chart Data
Because the unemployment rate for STEM Ph.D.’s is generally low, a more
useful indicator of job market strength is the number of STEM Ph.D.’s who
accept potentially permanent positions, compared with those who accept
postdocs. A considerable number of physics Ph.D.’s are unemployed,
accepting postdocs and other temporary positions (69 percent in 2010, as
opposed to 51 percent before the dot-com bust), indicating that the demand
for physics Ph.D.’s is not high. (See figure 2.)
View Chart Data
3. Geographic differences.There are also regional differences in the
labor markets for STEM workers. For example, software developers are in much
higher demand in California, Washington State, and New York, a fact that is
reflected in their higher wages in those states. (See figure 3.) This trend
is seen across different STEM occupations, and areas of demand vary.
Petroleum engineers, for instance, are clustered in Texas and Oklahoma. A
recruiter for a company in Connecticut stated that one of the primary
challenges he faced in hiring software developers was the location of the
office, because many qualified candidates were reluctant to relocate to
Connecticut.51Another recruiter mentioned that his company relocated to
the Boston area specifically to gain access to the local talent pool, a move
that improved recruitment.52
Summary
Across all the different disciplines, yes, there is a STEM crisis, and no,
there is no STEM crisis. It depends on how and where you look.
For most Ph.D.’s, the United States has a surplus of workers, especially in
tenure-track positions in academia. The exceptions are certain fields
within industry, such as petroleum engineering, process engineering, and
computer engineering, and other fields in the government sector, such as
nuclear engineering, materials science, and thermohydraulic engineering.
Academia tends to absorb the Ph.D.’s who are unable to find positions in
industry into postdoc positions. At the bachelor’s and master’s levels,
there is consistent demand for employees in software development, as well as
in high-growth areas such as mobile application development, data science,
and petroleum engineering. There is also demand below the bachelor’s level
in the manufacturing industry, which needs workers in the skilled trades,
such as machinists and technicians. Hence, we have aheterogeneousmixture
of supply and demand for different occupations: some have a queue of
workers, others a queue of unfilled positions.
Our findings are supported by the National Center for Education Statistics’
longitudinal study of baccalaureate holders, a survey which found that 69.7
% of graduates who had not enrolled in advanced-degree studies after they
completed their bachelor’s degrees in the 2007–2008 academic year were
employed in a full-time job with an annualized median salary of $46,000
between graduation and 2012.53For STEM majors, the full-time employment
rate increased to 77.2percent and the median salary was $60,000. However
, not all STEM majors were equally in demand: computer and information
sciences majors and engineering and engineering technology majors had full-
time employment rates of 77.1 percent and 83.2 percent, respectively, and
corresponding median salaries of $66,000 and $67,000, while graduates who
majored in the biological and physical sciences, science technology,
mathematics, or agricultural sciences had a full-time employment rate of 71.
4% with a median salary of $46,800, closer to that of non-STEM majors. These
data are consistent with our conclusion that there is significant variation
in the demand for graduates, depending on the STEM discipline.
Conclusion
This article draws upon a variety of data sources—professional science and
engineering societies, labor market data, the National Science Foundation,
literature reviews, and anecdotal accounts—to understand the supply-and-
demand landscape for the STEM labor market. The analysis presented offers a
first cut at identifying disciplines and degree levels that are either in
demand or oversupplied. A clearer picture of the supply and demand of the
STEM workforce will require better data and consistent monitoring of both
employer requirements and STEM worker availability.
We introduced the taxicab queuing model as a metaphor for the STEM labor
market. Depending on the STEM job segment, we can either have a queue of
positions waiting to be filled (cf. taxis) or a queue of STEM workers
waiting for jobs (cf. passengers). The characteristics of the queue depend
on different factors: the rate of job turnover (cf. taxi service rate); the
STEM worker arrival rate (cf. passenger arrival rate); the number of
positions available (cf. the number of taxis in the fleet); the location of
the job; the degree held by the worker (cf. type of taxi); and the worker’s
citizenship status. The model also highlights the probabilistic nature of
the supply-and-demand market: random fluctuations can cause job segments
that traditionally have a shortage of workers to have a surplus, and vice
versa. Although we currently lack the data to operationalize the model, it
presents a novel approach to characterizing the variation across STEM job
segments.
Our central question is whether there is a “STEM crisis” or a “STEM
surplus.” The answer is that both exist. Our analysis yields the following
findings:
The STEM labor market is heterogeneous. There are both shortages and
surpluses of STEM workers, depending on the particular job market segment.In
the academic job market, there is no noticeable shortage in any discipline.
In fact, there are signs of an oversupply of Ph.D.’s vying for tenure-
track faculty positions in many disciplines (e.g., biomedical sciences,
physical sciences).In the government and government-related job sector,
certain STEM disciplines have a shortage of positions at the Ph.D. level (e.
g., materials science engineering, nuclear engineering) and in general (e.g.
, systems engineers, cybersecurity, and intelligence professionals) due to
the U.S. citizenship requirement. In contrast, an oversupply of biomedical
engineers is seen at the Ph.D. level, and there are transient shortages of
electrical engineers and mechanical engineers at advanced-degree levels.In
the private sector, software developers, petroleum engineers, data
scientists, and those in skilled trades are in high demand; there is an
abundant supply of biomedical, chemistry, and physics Ph.D.’s; and
transient shortages and surpluses of electrical engineers occur from time to
time.The geographic location of the position affects hiring ease or
difficulty.
As our society relies further on technology for economic development and
prosperity, the vitality of the STEM workforce will continue to be a cause
for concern.
ACKNOWLEDGMENTS: Work on this project was supported by the National
Institutes of Health (NIH) under a grant titled “Developing a Scientific
Workforce Analysis and Modeling Framework (SWAM),” awarded to The Ohio
State University and the Massachusetts Institute of Technology (MIT), Center
for Engineering Systems Fundamentals (CESF)—NIH Grant # 5 U01 GM094141-02.
The discussion and conclusions presented are those of the authors and do
not necessarily represent the views of the NIH, The Ohio State University,
or MIT. We thank Joshua Hawley of The Ohio State University and Navid
Ghaffarzadegan of Virginia Tech for helpful comments on an earlier draft.
Notes
1President’s Council of Advisors on Science and Technology,Engage
to excel: producing one million additional college graduates with degrees in
science, technology, engineering, and mathematics(Executive Office of
the President of the United States, 2012).
2Michael Anft, “The STEM crisis: reality or myth?”The Chronicle of
Higher Education(November 11, 2013).
3B. Lindsay Lowell and Harold Salzman,Into the eye of the storm:
assessing the evidence on science and engineering education, quality, and
workforce demand(Washington, DC: Urban Institute, October 29, 2007);
Anthony P. Carnevale, Nicole Smith, and Michelle Melton,STEM: science,
technology, engineering, mathematics(Washington, DC: Georgetown
University Center on Education and the Workforce, 2011); and Terrence K.
Kelly, William P. Butz, Stephen Carroll, David M. Adamson, and Gabrielle
Bloom, eds.,The U.S. scientific and technical workforce(Santa Monica
, CA, Arlington, VA, and Pittsburgh, PA: RAND Corporation, June 2004).
4The taxicab queue is a classic queuing theory problem that models the
queues for taxis and passengers as a function of the arrival rates of
passengers and taxis and the size of the taxi fleet. The arrival rate of
passengers is modeled as a Poisson process, and the arrival time for a taxi
is modeled as a conditional Poisson process which depends on the number of
taxis that are currently busy. Numerical and graphical results of the
taxicab queuing model can be found in Yi Xue, “STEM Crisis or STEM Surplus?
” master’s thesis, Technology and Policy Program (Cambridge, MA:
Massachusetts Institute of Technology, 2014).
5Tapping America’s potential: the Education for Innovation Initiative(
Washington, DC, Business Roundtable, 2005);Ensuring a strong U.S.
scientific, technical, and engineering workforce in the 21st century(
Washington, DC: National Science and Technology Council, April 2000);The
science and engineering workforce: realizing America’s potential(Arlington,
VA: National Science Board, 2003).
6National Academy of Sciences, National Academy of Engineering, and
Institute of Medicine,Rising above the gathering storm: energizing and
employing America for a brighter economic future(Washington, DC: The
National Academies Press, 2007), pp. 1–591.
7Senator Bob Casey,STEM education: preparing for the jobs of the
future(Washington, DC: U.S. Congress Joint Economic Committee, April 2012).
8Engage to excel.
9“Testimony of Michael S. Teitelbaum before the Subcommittee on
Technology and Innovation,” November 6, 2007; see transcript,https://
science.house.gov/sites/republicans.science.house.gov/files/documents/
hearings/110607_teitelbaum.pdf.
10Lowell and Salzman,Into the eye of the storm.
11Hal Salzman, Daniel Kuehn, and B. Lindsay Lowell,Guestworkers in
the high-skill U.S. labor market: an analysis of supply, employment and wage
trends, EPI Briefing Paper no. 359 (Washington, DC: Economic Policy
Institute, April 24, 2013), pp. 1–35.
12Newsroom: Census Bureau reports majority of STEM college graduates do
not work in STEM occupations(U.S. Census Bureau, 2014). The U.S. Census
Bureau includes sales and managerial occupations, as well as social science
occupations, in its definition of STEM occupations.
13David George Kendall, “Some problems in the theory of queues,”
Journal of the Royal Statistical Society, Series B, vol. 13, no. 2, 1951, pp
. 151–185,http://www.jstor.org/stable/2984059?origin=JSTOR-pdf.
14Richard C. Larson, Navid Ghaffarzadegan, and Yi Xue, “Too many PhD
graduates or too few academic job openings: the basic reproductive number
0
2R0in academia,”Systems Research and Behavioral Science,
November/
December 2014, pp. 745–750.
15See Richard C. Larson and Mauricio Gómez Díaz, “Nonfixed retirement
age for university professors: modeling its effects on new faculty hires,”
Service Science, March 2012, pp. 69–78.
16Although only 294 of the 794 institutions have doctoral programs, the
number of faculty used in the calculation ofR0is the total for all
of those institutions, because the positions referred to are still tenured
and tenure-track faculty positions.
17Disciplines were included only if there were data available for both
the number of Ph.D.’s and the number of faculty.
18National Science Board,Science and engineering indicators 2014(
Arlington, VA: National Science Foundation, 2014).
19Beryl Lieff Benderley, “The real science gap,”Pacific Standard,
June 14, 2010,http://www.psmag.com/science/the-real-science-gap-16191.
20Henry Sauermann and Michael Roach, “Science PhD career preferences:
levels, changes, and advisor encouragement,”PLOS One, May 2, 2012,http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0036307.
21National Science Board,Science and engineering indicators 2014.
22Michael S. Teitelbaum,The current model of STEM graduate education
and postdocs: is it evolving to meet needs of the nation and its
participants?paper presented at the National Institutes of Health,
Washington, DC, November 5–6, 2007,http://rbm.nih.gov/stem/Teitelbaum.pdf.
a*u
6 楼
同问～
v*m
7 楼
n fact, there are signs of an oversupply of Ph.D.’s vying for tenure- track
faculty positions in many disciplines (e.g., biomedical sciences, physical
sciences).In the government and government-related job sector, certain STEM
disciplines have a shortage of positions at the Ph.D. level (e. g.,
materials science engineering, nuclear engineering) and in general (e.g. ,
systems engineers, cybersecurity, and intelligence professionals) due to the
U.S. citizenship requirement. In contrast, an oversupply of biomedical
engineers is seen at the Ph.D. level, and there are transient shortages of
electrical engineers and mechanical engineers at advanced-degree levels.In
the private sector, software developers, petroleum engineers, data
scientists, and those in skilled trades are in high demand; there is an
abundant supply of biomedical, chemistry, and physics Ph.D.’s; and
transient shortages and surpluses of electrical engineers occur from time to
time.The geographic location of the position affects hiring ease or
difficulty.
【在 v**********m 的大作中提到】
: http://www.bls.gov/opub/mlr/2015/article/stem-crisis-or-stem-su
: US Department of Labor
: A to Z Index|FAQs|About BLS|
: Contact Us
: U.S. Bureau of Labor Statistics
: Follow Us|What's New|Release Calendar|Site
: Map
: HomeSubjectsData ToolsPublicationsEconomic ReleasesStudentsBeta
: HOMEARCHIVESFOR AUTHORSABOUT
: ARTICLE
faculty positions in many disciplines (e.g., biomedical sciences, physical
sciences).In the government and government-related job sector, certain STEM
disciplines have a shortage of positions at the Ph.D. level (e. g.,
materials science engineering, nuclear engineering) and in general (e.g. ,
systems engineers, cybersecurity, and intelligence professionals) due to the
U.S. citizenship requirement. In contrast, an oversupply of biomedical
engineers is seen at the Ph.D. level, and there are transient shortages of
electrical engineers and mechanical engineers at advanced-degree levels.In
the private sector, software developers, petroleum engineers, data
scientists, and those in skilled trades are in high demand; there is an
abundant supply of biomedical, chemistry, and physics Ph.D.’s; and
transient shortages and surpluses of electrical engineers occur from time to
time.The geographic location of the position affects hiring ease or
difficulty.
【在 v**********m 的大作中提到】
: http://www.bls.gov/opub/mlr/2015/article/stem-crisis-or-stem-su
: US Department of Labor
: A to Z Index|FAQs|About BLS|
: Contact Us
: U.S. Bureau of Labor Statistics
: Follow Us|What's New|Release Calendar|Site
: Map
: HomeSubjectsData ToolsPublicationsEconomic ReleasesStudentsBeta
: HOMEARCHIVESFOR AUTHORSABOUT
: ARTICLE
l*d
8 楼
在哪里办理这个？谢～
【在 s***a 的大作中提到】
: 【 以下文字转载自 Returnee 讨论区 】
: 发信人: syria (syria), 信区: Returnee
: 标 题: 请问办理《留学回国人员证明》的毕业证复印件必须是公证过的吗？
: 发信站: BBS 未名空间站 (Fri Jul 2 02:55:17 2010, 美东)
: 直接复印一下毕业证不行吗？
【在 s***a 的大作中提到】
: 【 以下文字转载自 Returnee 讨论区 】
: 发信人: syria (syria), 信区: Returnee
: 标 题: 请问办理《留学回国人员证明》的毕业证复印件必须是公证过的吗？
: 发信站: BBS 未名空间站 (Fri Jul 2 02:55:17 2010, 美东)
: 直接复印一下毕业证不行吗？
v*m
9 楼
At the same time that shortages exist, there are areas with surpluses of
STEM talent—most notably, biomedical Ph.D.’s. An NIH blue- ribbon panel
found an increasing number of biomedical Ph.D.’s working in science-related
occupations that do not involve research and even that do not require
graduate training in science.46 Chemistry and biomedical graduates also have
taken a hard hit, due to the downsizing and offshoring of biotechnology,
chemical, and pharmaceutical jobs.47 Since 2000, U.S. pharmaceutical
companies have cut 300,000 jobs.48 By 2012, downsizing had increased the
unemployment rate among chemists to 4.6 percent, the highest in 40 years.
One recruiter we interviewed said he found that many chemical engineering
college graduates were seeking employment in software development.49 Among
young Ph.D.’s, the situation was even worse: just 38 percent of newly
minted chemistry Ph.D.’s were employed in full-time, nonpostdoc positions
in 2011, down from 51 percent in 2008.50 New chemical engineering Ph.D.’s
fared better, with a full-time, nonpostdoc employment rate of 61 percent.
track
physical
STEM
the
【在 v**********m 的大作中提到】
: n fact, there are signs of an oversupply of Ph.D.’s vying for tenure- track
: faculty positions in many disciplines (e.g., biomedical sciences, physical
: sciences).In the government and government-related job sector, certain STEM
: disciplines have a shortage of positions at the Ph.D. level (e. g.,
: materials science engineering, nuclear engineering) and in general (e.g. ,
: systems engineers, cybersecurity, and intelligence professionals) due to the
: U.S. citizenship requirement. In contrast, an oversupply of biomedical
: engineers is seen at the Ph.D. level, and there are transient shortages of
: electrical engineers and mechanical engineers at advanced-degree levels.In
: the private sector, software developers, petroleum engineers, data
STEM talent—most notably, biomedical Ph.D.’s. An NIH blue- ribbon panel
found an increasing number of biomedical Ph.D.’s working in science-related
occupations that do not involve research and even that do not require
graduate training in science.46 Chemistry and biomedical graduates also have
taken a hard hit, due to the downsizing and offshoring of biotechnology,
chemical, and pharmaceutical jobs.47 Since 2000, U.S. pharmaceutical
companies have cut 300,000 jobs.48 By 2012, downsizing had increased the
unemployment rate among chemists to 4.6 percent, the highest in 40 years.
One recruiter we interviewed said he found that many chemical engineering
college graduates were seeking employment in software development.49 Among
young Ph.D.’s, the situation was even worse: just 38 percent of newly
minted chemistry Ph.D.’s were employed in full-time, nonpostdoc positions
in 2011, down from 51 percent in 2008.50 New chemical engineering Ph.D.’s
fared better, with a full-time, nonpostdoc employment rate of 61 percent.
track
physical
STEM
the
【在 v**********m 的大作中提到】
: n fact, there are signs of an oversupply of Ph.D.’s vying for tenure- track
: faculty positions in many disciplines (e.g., biomedical sciences, physical
: sciences).In the government and government-related job sector, certain STEM
: disciplines have a shortage of positions at the Ph.D. level (e. g.,
: materials science engineering, nuclear engineering) and in general (e.g. ,
: systems engineers, cybersecurity, and intelligence professionals) due to the
: U.S. citizenship requirement. In contrast, an oversupply of biomedical
: engineers is seen at the Ph.D. level, and there are transient shortages of
: electrical engineers and mechanical engineers at advanced-degree levels.In
: the private sector, software developers, petroleum engineers, data
j*a
10 楼
这边的公证连个ups店都能做 无所谓
【在 s***a 的大作中提到】
: 【 以下文字转载自 Returnee 讨论区 】
: 发信人: syria (syria), 信区: Returnee
: 标 题: 请问办理《留学回国人员证明》的毕业证复印件必须是公证过的吗？
: 发信站: BBS 未名空间站 (Fri Jul 2 02:55:17 2010, 美东)
: 直接复印一下毕业证不行吗？
【在 s***a 的大作中提到】
: 【 以下文字转载自 Returnee 讨论区 】
: 发信人: syria (syria), 信区: Returnee
: 标 题: 请问办理《留学回国人员证明》的毕业证复印件必须是公证过的吗？
: 发信站: BBS 未名空间站 (Fri Jul 2 02:55:17 2010, 美东)
: 直接复印一下毕业证不行吗？
v*m
11 楼
船在下沉，没必要陪葬。
转马工的同学，统计局已经注意到你们了，为美帝分忧，值得表扬。
要说黑生物职业，谁也比不上这个有分量。这是在国家层面在主动黑。
学术界上层吸血鬼阶层为了维持他们自己不垮台，在向国家哭穷要经费的同时继续无序
不负责任的扩大trainee的蓄水池。
related
have
【在 v**********m 的大作中提到】
: At the same time that shortages exist, there are areas with surpluses of
: STEM talent—most notably, biomedical Ph.D.’s. An NIH blue- ribbon panel
: found an increasing number of biomedical Ph.D.’s working in science-related
: occupations that do not involve research and even that do not require
: graduate training in science.46 Chemistry and biomedical graduates also have
: taken a hard hit, due to the downsizing and offshoring of biotechnology,
: chemical, and pharmaceutical jobs.47 Since 2000, U.S. pharmaceutical
: companies have cut 300,000 jobs.48 By 2012, downsizing had increased the
: unemployment rate among chemists to 4.6 percent, the highest in 40 years.
: One recruiter we interviewed said he found that many chemical engineering
转马工的同学，统计局已经注意到你们了，为美帝分忧，值得表扬。
要说黑生物职业，谁也比不上这个有分量。这是在国家层面在主动黑。
学术界上层吸血鬼阶层为了维持他们自己不垮台，在向国家哭穷要经费的同时继续无序
不负责任的扩大trainee的蓄水池。
related
have
【在 v**********m 的大作中提到】
: At the same time that shortages exist, there are areas with surpluses of
: STEM talent—most notably, biomedical Ph.D.’s. An NIH blue- ribbon panel
: found an increasing number of biomedical Ph.D.’s working in science-related
: occupations that do not involve research and even that do not require
: graduate training in science.46 Chemistry and biomedical graduates also have
: taken a hard hit, due to the downsizing and offshoring of biotechnology,
: chemical, and pharmaceutical jobs.47 Since 2000, U.S. pharmaceutical
: companies have cut 300,000 jobs.48 By 2012, downsizing had increased the
: unemployment rate among chemists to 4.6 percent, the highest in 40 years.
: One recruiter we interviewed said he found that many chemical engineering
j*a
12 楼
使馆
【在 l********d 的大作中提到】
: 在哪里办理这个？谢～
【在 l********d 的大作中提到】
: 在哪里办理这个？谢～
l*8
13 楼
国内机会可能大一些。
s*g
14 楼
公正很多地方都可以做 但是回国证明必须在使馆
话说现在还需要做这个么？
话说现在还需要做这个么？
v*m
15 楼
美国有86000的千老没出路，其中一半以上估计是大陆培养的，这些人要是不转行，中
国也会重复美国的情况。
【在 l********8 的大作中提到】
: 国内机会可能大一些。
国也会重复美国的情况。
【在 l********8 的大作中提到】
: 国内机会可能大一些。
E*T
16 楼
要这个证 做什么用啊？
s*y
17 楼
不是中国重复美国，是中国一直在美国前头
否则也不会有这么多人来美国当千老搬砖了，还有很多自带干粮搬砖的（政府补贴嫖资
的访学和交换学生）。
说明中国已经先于美国无法承载这么多皮挨着地了。
生物在国内说是上天无路入地无门一点都不夸张。
【在 v**********m 的大作中提到】
: 美国有86000的千老没出路，其中一半以上估计是大陆培养的，这些人要是不转行，中
: 国也会重复美国的情况。
否则也不会有这么多人来美国当千老搬砖了，还有很多自带干粮搬砖的（政府补贴嫖资
的访学和交换学生）。
说明中国已经先于美国无法承载这么多皮挨着地了。
生物在国内说是上天无路入地无门一点都不夸张。
【在 v**********m 的大作中提到】
: 美国有86000的千老没出路，其中一半以上估计是大陆培养的，这些人要是不转行，中
: 国也会重复美国的情况。
t*7
18 楼
在中国柱洛杉矶总领事馆 一号窗口办， 就是你们一般去领passport visa 的楼的对面
， 你们可以打电话给他们先， 问个清楚， 一般1－2个礼拜
， 你们可以打电话给他们先， 问个清楚， 一般1－2个礼拜
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