Estimating the increase in wages from military service.
Kogut, Carl A. ; Short, Larry E. ; Wall, Jerry L. 等
INTRODUCTION
The benefits of higher education for individuals is well documented
in that there is a positive correlation between higher levels of
education and higher earnings for all racial/ethical groups and for both
men and women (College Board, 2007). Can the same benefits be obtained
for military service? That is, does business and industry value an
individual's service in the all-volunteer military by awarding an
earnings premium for such service--and if so, does the earnings premium
exist regardless of race and gender? Can military service be a
substitute for higher education? Specifically, can an individual
graduating from high school make a choice to enter the military instead
of going to college and reap benefits in terms of increased earnings in
civilian employment? This study will attempt to ascertain if service in
the all-volunteer military can provide a similar advantage in terms of
higher earnings that higher education has done over the years.
The value of military service to civilian employment has been
studied intensively over the past 50 years. Most early studies of
veterans of World War II and Korea found that, over the long run, these
veterans had higher earnings than non-veterans (Martindale and Poston,
1979; Little and Fredland, 1979). The earning premium earned by World
War II and Korea veterans over non-veterans appeared to exist regardless
of veterans' race (Villemez and Kasarda, 1976; Mardindale &
Poston, 1979; Little and Fredland, 1979). Studies of Vietnam-era
veterans suggested that military service did not have the same
consistent income premium impact on civilian earnings that WWII and
Korean veterans enjoyed (Schwartz, 1986; Martindale & Poston, 1979;
Berger & Hirsch, 1983). Minority group veterans of the Vietnam-era,
however, appeared to receive civilian earning benefits, when compared to
comparable non-veterans, while many non-minority veterans suffered an
income disadvantage (Poston, 1979). Interestingly, some studies found
that the Vietnam-era veterans with less education often received a
larger civilian earnings premium than those with more education
(Villemez and Kasarda, 1976; Rosen and Taubman, 1982; Berger and Hirsch,
1983).
After the end of the compulsory draft in 1973, researchers began to
study the effect that service in the all-volunteer armed forces had on
subsequent civilian earnings including protected group veterans, i.e.,
women and minority group members. A study in 1993 found that the impact
of service in the all-volunteer military on subsequent civilian earnings
differed with race and education; non-whites and high school dropouts
benefited from service in the military while college graduates suffered
a large earnings penalty (Bryant, Samaranayake, and Wilhite, 1993).
Studies of the earnings premiums of female veterans appear somewhat
mixed with one study finding an earnings advantage to female veterans
(Mehay and Hirsch, 1996), another finding an earnings advantage to older
female veterans and a penalty to younger female veterans (Prokos and
Padavic, 2000), and another finding female veterans losing ground
relative to their female nonveteran civilian counterparts (Cooney,
Segal, Segal, and Falk, 2003).
PURPOSE OF THE STUDY
The purpose of this study is to determine if an earnings premium
exists for veterans of the all-volunteer military, and if such exists,
to estimate the increase in earnings that results from serving in the
all-volunteer military, and to compare that return to the benefit from
attaining additional education.
METHODOLOGY
This study employs a variant on the standard human capital wage
equation used by most researchers by including a variable to capture the
effect on wages from military service. Although most studies typically
exclude women from the analysis due to their intermittent labor force
participation which renders age an inappropriate measure for experience,
we have elected to include females in the first model since they are
becoming an increasingly important part of the all-volunteer armed
services. Model 2 is the more traditional form which excludes females
from the analysis so these results can be compared to the more
traditional estimating equation. Model 3 replicates the analysis on just
females to compare to the results in Model 2. The regression analysis is
also done separately by education groups defined as 1) those with a high
school diploma or equivalent, 2) those who had some college education,
3) those who graduated college with a Bachelor's degree, 4) those
who attained a Master's degree, and 5) those who attained a
Professional or Doctoral level degree. The equations estimated are as
follows:
Model 1
LogWage = a + [b.sub.1] Age + [b.sub.2][Age.sup.2] +
[b.sub.3]Married + [b.sub.4]Black + [b.sub.5]Other + [b.sub.6] Male +
[b.sub.7]Military + [euro]
Models 2 and 3
LogWage = a + [b.sub.1] Age + [b.sub.2][Age.sup.2] +
[b.sub.3]Married + [b.sub.4]Black + [b.sub.5]Other + [b.sub.6]Military +
[euro]
where:
LogWage = natural log of the hourly wage
Age = the age (in years) for the individual and [Age.sup.2] is the
square of Age
Married = 1 if the individual is married, spouse present
Black = 1 if the individual is only Black
Other = 1 if the individual is neither just Black nor just White
Male = 1 if male
Military = 1 if the individual served in the military
Thus, the base group in Models 1 and 3 consists of single white
females who did not serve in the military, while in Model 2 the base
group is single white males without military service.
DATA
The source of the data for this study is the 2009 Current
Population Survey March Supplement. The CPS is a monthly survey of over
50,000 households conducted by the Bureau of the Census for the Bureau
of Labor Statistics and is the official Government statistics on
employment and unemployment. The sample is scientifically selected to
represent the civilian non-institutional population of the United
States. The sample population is located in 792 sample areas comprising
2,007 counties and independent cities with coverage in every State and
in the District of Columbia. Currently CPS interviews about 57,000
households monthly. The CPS is the primary source of information on
labor force characteristics of the U.S. population and CPS data are used
by government policy makers and legislators as important indicators of
our nation's economic situation (US Census Bureau, 2009).
Since this study attempts to determine the impact that service in
the all-volunteer military has upon civilian pay, the samples we used
for analysis were limited by three decision rules. First, only
year-round, full-time workers were included in the sample. The U.S.
Bureau of Labor Statistics defines year-round workers as being employed
for at least 50 weeks a year and fulltime workers as working 35 or more
hours a week. Second, a minimum age restriction of 25 years was imposed
to permit personnel sufficient time to complete their military service
and enter the civilian workforce. Third, a maximum age restriction of 53
years was imposed to ensure that only military personnel who volunteered
for military service were included in the sample. The military draft was
eliminated in 1973, thus any veteran between the ages of 25 and 53 at
the time the CPS data was collected would have voluntarily joined the
military.
Table 1 presents the sample mean age and percentages for each of
the education groups. A few interesting results are readily noticeable.
First, the percentage of individuals who are married increases as
education level increases. Second, the percentage Black falls with
education level while the percentage Other rises, peaking at the
Professional/Doctoral level. Finally, the percent with military service
rises to those with some College education but then falls for those with
even higher levels of education.
RESULTS
Table 2 reports the estimated coefficients from Model 1. The first
six rows report the usual regression coefficients from earnings equation
estimates. Age and its square term are both significant at greater than
the 1% level across all education groups and the signs imply the usual
age-earnings profile; the log of wages increases at a decreasing rate.
The coefficient estimates on Married are also positive and significant
at greater than the 1% level across all education groups. This premium
to being married is commonly interpreted to exist because being married
serves as a proxy for things such as stability and motivation. It should
be noted that the size of the coefficient is somewhat less than commonly
reported (see for example, Newman 1988), since those equations are
usually estimated with just males. The coefficient estimates in Model 2
indicate a higher premium, similar to other studies.
The race coefficients, Black and Other, are negative across all
education groups, but the significance of the coefficients falls from
being significant at greater than a 1% level at low education levels to
being insignificant (less than 10%) at higher education levels. That
would indicate that any bias against minorities tends to diminish as
those individuals attain jobs that require higher levels of education.
The coefficients associated with Male are positive across all
education levels and indicate a highly significant (greater than 1%)
difference in the earnings of males versus females ranging from about
23% to approximately 26%. As mentioned above, including females in these
earnings equation estimates is somewhat unusual, but the result that
males earn more than females is well known (See, for example, BLS 2009).
The variable Military measures the impact from military service on
earnings. The coefficient estimates are positive across all education
levels, but only for those with Some College or less are the estimates
significant. This indicates that military service has a much greater
impact for those who do not pursue higher education. Although military
service does have a positive impact on earnings, the effect is clearly
greater for those who just graduate from high school or only spend some
time in college. There is a 12% premium to those with just a high school
degree and a nearly 10% premium if they attend, but never graduate from
college. A typical teenager who graduates from high school faces a
decision about whether to join the military, go directly to college, or
simply enter the workforce. Our results indicate that a white male who
is 40 years old, married and only has a high school education will
receive, on average, an hourly wage of approximately $15.84. But a
married, 40 year old white male with only a high school education who
also served in the military can expect an hourly wage of approximately
$17.91. However, that increase in wages due to military service pales in
comparison to what the same person with a college degree will earn
(i.e., $29.63 per hour).
Table 3 reports the regression coefficients for Model 2 which
estimates the earnings equation for males alone. Interestingly, the age
variables are essentially the same so the argument that these sorts of
studies should be done only on males seems questionable. However, our
results from Model 3 show that the size of the coefficient estimates for
females alone are significantly less than for males. More study would be
necessary to further examine these results.
One major difference in the results in Model 2 compared to Model 1
is the impact from being married. The premium for males alone appears to
be almost double than what is estimated for all workers.
Another interesting difference in the estimates for just males
compared to all workers is the size of the negative coefficients on
Black. The negative impact from race on just males is nearly twice as
large as it is for all workers. Thus, it appears that any discrimination
that still exists in terms of earnings is directed mostly at black
males.
Finally, comparing the Military variable in the two models we see
that the effect from military service disappears at higher education in
both. We also see that the estimated increase in wages is lower for
males than for everyone. That result becomes clearer when considering
the estimates from Model 3.
Table 4 reports the regression coefficients for Model 3 which
estimates earnings for females only. Interestingly, although the size of
the coefficient estimates for Age and Age Squared are smaller than they
are for males alone, they generally still indicate the same earnings
profile. The effect of being married is also much lower and in most
cases, insignificant. Thus, although being married is seen as a positive
influence on earnings for males, it doesn't make any real
difference for females. There also appears to be less racial bias for
females than males but that result is not uncommon, especially for
CPS-type data (Neal, 2004). Most importantly for our purposes here, the
coefficients on Military have the same pattern we observed for males,
there is a positive and significant impact on earnings for those with
Some College or less, but that effect disappears once a college degree
has been attained. However, the size of the coefficients are
significantly larger, indicating a 16% and 12% wage premium from
military service for females with a high school degree or some college
respectively. Thus, it appears that female military service is more
highly rewarded than military service by males. That could be due to
supply effects in the sense that there are many fewer females with
military service than males. There is also the "novelty"
factor in that female veterans are still a relatively new group.
CONCLUSIONS
Our results indicate that there is a definite increase in earnings
for those who choose to serve in the military and that female veterans
are more highly rewarded than male veterans. The increase is strongest
among those with lower education attainment and fades as the level of
education increases. If an individual is either unable to go to college
or chooses not to go, then that individual should certainly consider
joining the military as a way to increase lifetime earnings. Although
military service is not a substitute for education, we've estimated
that it can be somewhat of a complement in that wages will be about 10%
higher for males with military service, at least at lower education
levels. In addition, the increase in wages from military service at
lower education levels is even more pronounced for females (about 12%).
REFERENCES
Berger, Mark C. and Barry T. Hirsch. 1983. "The Civilian
Earnings Experience of Vietnam-Era Veterans." The Journal of Human
Resources, 17(4): 455-479.
Bryant, Richard R, V.A. Samaranayake and Allen Wilhite. (1993).
"The Effect of Military Service on the Subsequent Civilian Wage of
the Post-Vietnam Veteran." The Quarterly Review of Economics and
Finance, 33(1): 15-31.
College Board. 2007. Trends in Higher Education Series. Washington,
D. C.: The College Board.
Cooney, Jr., Richard T., Mary Wechsler Segal, David G, Segal, and
William W. Falk. 2003. "Racial Differences in the Impact of
Military Service on the Socioeconomic Status of Women Veterans."
Armed Forces and Society, 30(1): 53-86.
Little, R.D. and J.E. Fredland. (1979). "Veterans Status,
Earning, and Race," Armed Forces & Society, 5(2): 244-260.
Martindale, Melanie and Dudley L. Poston, Jr. 1979.
"Variations in Veteran/Nonveteran Earnings Patterns Among World War
II, Korea, and Vietnam War Cohorts." Armed Forces and Society, 5:
219-243.
Mehay, Stephen L. and Barry T. Hirsch. 1996. "The Postmilitary
Earnings of Female Veterans." Industrial Relations, 35(2): 197-217.
Neal, Derek. 2004. "The Measured Black-White Wage Gap among
Women Is Too Small." Journal of Political Economy, 112(S1): S1-S28.
Poston, Jr., Dudley L. (1979). "The Influence of Military
Service on the Civilian Earnings Patterns of Blacks, Mexican Americans,
and Anglos." Journal of Political and Military Sociology, 7: 71-88.
Prokos, Anastasia and Irene Padavic. 2000. "Earn All That You
Can Earn: Income Difference Between Women Veterans and
Non-Veterans." Journal of Political and Military Sociology, 28(1):
60-74.
Rosen, Sherwin and Paul Taubman. 1982. "Changes in Life-Cycle
Earnings: What Do Social Security Data Show?" Journal of Human
Resources, 17: 321-38.
Schwartz, Saul. 1986. "The Relative Earnings of Vietnam and
Korean-Era Veterans." Industrial and Labor Relations Review, 39(4):
564-572.
U.S. Department of Labor, U.S. Bureau of Labor Statistics, July
2009, Report 1017, "Highlights of Women's Earnings in
2008".
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Carl A. Kogut, University of Louisiana at Monroe
Larry E. Short, Northwestern State University
Jerry L. Wall, Northwestern State University
Table 1
Sample Averages
Some College Prof/
Variable HS Grad College Grad Masters Doctorate
Age 40.2 39.8 39.4 40.3 41.4
Married 63.80% 64.10% 69.10% 73.70% 77.10%
Black 12.30% 12.40% 8.10% 8.90% 5.70%
Other 7.00% 7.90% 10.50% 12.70% 16.10%
Male 60.30% 52.80% 54.80% 52.10% 62.90%
Military 6.70% 8.40% 4.60% 5.00% 3.50%
Num obs 14,317 14,651 12,129 4,480 1,879
Table 2
Regression Coefficient Estimates--Model 1
Some College
Variable HS Grad College Grad
Intercept 1.5415 * 1.5832 * 1.1370 *
Age 0.0425 * 0.0479 * 0.0873 *
Age Squared -0.0005 * -0.0005 * -0.0010 *
Married 0.0762 * 0.0994 * 0.1153 *
Black -0.0670 * -0.648 * -0.0904 *
Other -0.0713 * -0.0631 * 0.0151
Male 0.2447 * 0.2269 * 0.2446 *
Military 0.1230 * 0.0975 * 0.016
F-Statistic 130.60 * 151.27 * 114.46 *
Prof/
Variable Masters Doctorate
Intercept 1.5127 * 0.59
Age 0.0747 * 0.1265 *
Age Squared -0.0008 * -0.0014 *
Married 0.1072 * 0.1325 *
Black -0.0759 ** 0.0767
Other -0.0101 -0.0631
Male 0.2605 * 0.2271 *
Military 0.0608 0.0418
F-Statistic 60.04 * 16.09 *
Note: * = Significant at the .01 level, ** = Significant at the .05
level
Table 3
Regression Coefficient Estimates--Model 2
Some College
Variable HS Grad College Grad
Intercept 1.5734 * 1.6121 * 1.1050 *
Age 0.0519 * 0.0568 * 0.0967 *
Age Squared -0.0006 * -0.0006 * -0.0011 *
Married 0.1409 * 0.1653 * 0.2202 *
Black -0.1264 * -0.1229 * -0.2313 *
Other -0.1196 * -0.1058 * 0.0318
Military 0.0934 * 0.0790 * 0.0055
F-Statistic 63.81 * 71.98 * 67.92 *
Prof/
Variable Masters Doctorate
Intercept 1.6275 * 0.8677
Age 0.0771 * 0.1204 *
Age Squared -0.0008 * -0.0013
Married 0.1570 * 0.2576 *
Black -0.1555 * 0.1096
Other -0.0206 -0.1546 **
Military 0.0607 0.0016
F-Statistic 20.22 * 8.44 *
Note: * = Significant at the .01 level, ** = Significant at the .05
level
Table 4
Regression Coefficient Estimates--Model 3
Some College
Variable HSGrad College Grad
Intercept 2.09 * 1.77 * 1.51 *
Age 0.01 0.04 * 0.07 *
Age Squared -0.00009 -0.0004 * -0.0009 *
Married 0.009 0.040 * 0.017
Black -0.029 -0.053 * -0.004
Other -0.034 -0.041 0.054 **
Military 0.158 ** 0.117 * -0.035
F-Statistic 13.58 * 26.73 * 13.54 *
Prof/
Variable Masters Doctorate
Intercept 1.50 * 0.42
Age 0.08 * 0.14 *
Age Squared -0.0009 * -0.0015 *
Married 0.063 ** 0.014
Black -0.016 0.063
Other 0.004 0.87
Military 0.023 0.098
F-Statistic 9.31 * 4.19 *
Note: * = Significant at the .01 level, ** = Significant at the .05
level