Gender effect on the perceived value of human capital in management.
Brahmasrene, Tantatape ; Chaiprasop, Ruangthong
ABSTRACT
This study examined earnings inequality in Thailand. There is a
relatively higher ratio of men than women in high level management
positions in manufacturing. Women are typically employed in lower level
positions such as bookkeeping, human resources and secretarial staff.
They are the main force in the service sector such as banking, retail
trades, education, hospitality and tourism. The trend has shifted in
recent years when more women than men enter into a managerial level
position. However, earnings for women are relatively lower than that of
their male counterparts.
A human capital model was employed to assess factors affecting
earnings among men and women at managerial levels. These factors
included education, work experience, marital status, job satisfaction,
number of hours at work and at home, willingness to engage in frequent
business trips and gender. The empirical analysis found that education,
work experience, marital status and willingness to engage in frequent
business trips had a significant effect on all samples in the study.
Education and work experience profoundly affected earnings for both men
and women. However, only women's earnings were affected by marital
status and willingness to engage in frequent business trips.
INTRODUCTION
Thailand is currently undergoing reforms and adjustments in
economic development planning aimed at bolstering market confidence and
achieving economic recovery and stability. Amidst the past financial
crisis, female employment has played an important role in the Thai
economy, especially in the private sector. Table 1 provides selected
statistics to compare males and females in the labor force. The Thai
labor force is about 57 percent male and 43 percent female. More than
twice the number of administrative, managerial and professional workers
reside in an urban area. The percentage of women in administrative,
managerial and professional positions increased from 49.7 in 1996 to
56.8 percent in 2000. There have been more job opportunities and better
career advancement for women in the modern private sector. However,
women with college degrees continue to earn less than their male
counterparts. Wage and earnings inequality may arise due to
heterogeneous jobs and workers. The initial motivation behind this
research was to assess the impact of crucial factors affecting earnings
at the entry to middle managerial levels in Thailand in order to control
for some consequences of heterogeneities. Previous research has shown
gender effect on employment and earnings inequality mainly among low
educated and unskilled workers. Higher educated women at the managerial
level have rarely been investigated.
REVIEW OF RELATED LITERATURE
The US historical trend in the female-male ratio indicated a rapid
increase during the 1980s and stood at .72 by 1990 (O'Neill &
Polachek, 1993). American women's economic status improved
significantly in the 1980s. Understanding the gender gap in pay is
important because even in the absence of any labor-market
discrimination, it is unlikely that the wage rates of women and men
would be equal (O'Neill, 2003). The relative improvement in
women's wages can be attributed to an increase in labor market experience and work attachment (Blau & Kahn, 1997; O'Neill
& Polachek, 1993). Not only can changes in the structure of the
economy affect the wage distribution, but also human capital investments
can create income inequality within a particular population.
Earnings dispersion generally occurs due to differences in job
characteristics and worker skills. Conversely, earnings inequality may
occur among equally skilled workers in the same job because of gender,
race and other irrelevant characteristics. It is widely accepted that
differences in human capital between men and women do matter (Borjas,
2000). Men tend to acquire more human capital than women. The human
capital that women acquire depreciates somewhat during the child bearing
years when they engage in household production. According to Polachek
(1981), women who wish to maximize the present value of lifetime
earnings will not enter occupations where their skills will depreciate rapidly during the child bearing years. The human capital explanation of
gender wage differential states that because women have shorter payoff
periods, they invest less in on-the-job training and other forms of
human capital, and hence have lower wages. Becker (1985) pointed out
that women remained largely responsible for child care and household
production with high effort intensive. Thereby, married women seek
occupations that require less effort. They segregate themselves into
less demanding occupations. In addition, wage depends not only on hours
worked but also work effort. Hence, women's earnings are lower.
Lower wages lead to less incentive to work. Gronau (1988) and Neumark
(1995) examined whether a woman weaker work's attachment resulted
in a lower wage or whether the lower wage led to less work attachment.
Some studies (England, Farkas, Kilbourne and Dou, 1998; Macpherson &
Hirsch, 1995) investigated the relationship between women's
employment and earnings in a particular occupation. After holding
constant the human capital and other socioeconomic characteristics,
these studies found that female jobs pay lower wages.
Michael (1973) further investigated how human capital influenced
various aspect of a worker's behavior. Macpherson and Hirsch (1995)
found that women in a profession where at least seventy five percent of
the coworkers were women earned fourteen percent less than comparable
women in a profession where less than twenty five percent of the
coworkers were women. In contrast, a man in a predominantly female
profession earned fourteen percent less than a man in a predominantly
male profession.
HYPOTHESIS
The above literature review leads to the hypothesis that earnings
are affected by three categories of independent variables: human capital
variables, worker characteristics and working conditions.
Human capital variables include educational attainment (ED) and
years of work experience (WORK). Mincer (1974), employing earnings power
function, found the direct effect of years of education and work
experience on earnings. Educational attainment augments a worker's
productivity via enhancement of his/her abilities or skills, especially
cognitive skills. A more educated and better trained worker is able to
offer a greater productive potential than one with less education and
training. Additional years of education will increase an
individual's productivity. Johnson, Palermo, and Asgary (2002)
found positive effects of increased literacy on wages in manufacturing
in their international study. Mincer (1974) indicated that once the
postschooling on-the-job training investment was included in the human
capital definition, one-half to two-thirds of the personal earning
variations were explained. Over time, workers may acquire human capital
through work experience and thereby increase earnings (Mincer, 1974;
Naderi & Mace, 2003). Acquired additional job skill increases
productivity. Increase in marginal productivity results in higher
earning. Thus, education and work experience positively affect earnings
(Y).
Worker characteristics may include marital status (MSTATUS), weekly
hours worked at the office (HRWORK) and at home (HRHOME) and gender
(GENDER). Schumann, Ahlburg and Mahoney (1994) examined the influence of
both the worker characteristics and job characteristics on earnings.
Data were collected specifically for this purpose. They found that both
worker characteristics and job characteristics were important
determinants of pay. In addition, women held jobs that were of lower
value to the firm. This explains part, but not all, of the gross
male-female pay differential.
Marital status is expected to have either positive or negative
influence on earnings. Married persons may have a greater incentive to
increase earnings to support their families. On the other hand, married
women may engage in occupations that require less effort in order to
spend more time providing for child care and household production. This
leads to lower earnings. Time spent in the office increases productivity
if it is time well spent, but the fact that most women continue to take
the primary responsibility for child care is a cause of distraction,
diversion, anxiety and absenteeism (Schwartz, 1989). Hill (1983)
investigated allocation of weekly hours to various activities by gender
and marital status. Women allocated more hours to the non-market sector
than men. Married women worked about 35 hours per week as compared to 14
hours for married men. However, the total hours at work and at home were
above 50 hours per week for both genders. While weekly hours worked at
the office is positively related to earnings, weekly hours worked at
home is expected to have a negative impact on earnings.
Working conditions are reflected in job satisfaction (JOBSAT) and
willingness to engage in frequent business trips (FREQUENT). Job
satisfaction is conceived in terms of a worker's general reaction
to the job without reference to any specific job facets (Hamermesh,
1977). Higher job satisfaction results in higher productivity and
thereby increases earnings. Schumann, Ahlburg and Mahoney (1994)
indicated that the characteristics of both workers and jobs determine
pay. The introduction of job characteristics to the pay function reduces
the male-female pay differential. Willingness to engage in business
trips frequently (FREQUENT) is a newly introduced factor in this paper
that represents job characteristics and preference or tastes. If women
prefer jobs that require fewer business trips, then the exercise of this
preference may result in lower earnings. This should directly relate to
earnings.
For empirical analysis, the model has been constructed as shown
below:
Y or LnY = CONSTANT + b1ED + b2WORK + b3MSTATUS + b4JOBSAT +
b5HRWORK + b6HRHOME + b7FREQUENT + b8GENDER + ui
Description of variables is summarized in Table 2. ui is a
stochastic error term or disturbance term.
First, two models are estimated by controlling the gender variable.
In effect, the first model was estimated based upon men's earnings,
the second model on women's earnings. The last model includes
gender variables, along with other independent variables, to determine
whether the gender variable is statistically significant.
DATA AND METHODOLOGY
The data source used in this study is an original survey conducted
in 36 parts of the Bangkok Metropolitan Area in 2002. A stratified simple random sampling was employed to obtain sample managers from two
groups of establishments, which included (1) manufacturing, handicraft,
construction, transportation, and (2) retail and service industries. The
population was restricted to entry to middle level men and women
managers in establishments of more than twenty employees. The number of
returned surveys totaled 203. Of those surveys completed and returned,
some had one or more items on the survey left blank. Therefore, 198
observations were analyzed. Members of the sample surveyed ranged in age
from 21-58 years, and 63 percent were married. Education ranged from
high school diplomas to Master's degrees.
Further data exploration is shown in Table 3, Subpopulation Differences. By and large, women managers' monthly earnings were
about 8 percent less than men's earnings. Monthly earnings are
shown in Thai baht (approximately 40 Baht = 1 US dollar). Married
persons earned 54 percent more than singles. Over all, when compared
with women, men managers showed slightly higher education (16.30 VS
15.83 years), years of work experiences (6.82 VS 6.32), job satisfaction
(.81 VS .69) and willingness to engage in frequent business trips (.65
VS .55). They also reported fewer numbers of hours worked in the office
(44.76 VS 46.04) and at home (6.43 VS 9.83).
The ordinary least square (OLS) method was employed to test the
above hypotheses. One of the tasks in performing regression analysis with several independent variables was to calculate a correlation matrix for all variables. Table 3 reports the Pearson Correlations for all
variables. Monthly managers' earnings were highly correlated with
education attainment, years of work experience and marital status (<
0.01). There were no particularly large intercorrelations among
independent variables. However, a measure of multicollinearity among
independent variables would be performed.
EMPIRICAL RESULTS
The assumption of linear multiple regression and the fitness of the
model was tested with no apparent violation. According to the computed
values of a multiple regression model, the null hypothesis was rejected
at a significant level of less than 0.01 (F test) in all three earnings
models shown in Table 5. This means that among these estimated
equations, there existed a relationship between earnings and the
explanatory variables; education, years of work experience, marital
status, job satisfaction, weekly hours worked at the office and home,
willingness to engage in frequent business trips and gender (for third
model only). The variance inflation factor (VIF) is presented in Table 5
to detect multicollinearity among independent variables. A value of VIF
less than 10 generally indicates no presence of multicollinearity. It
appears that the observed dependencies did not affect their
coefficients.
The coefficient of multiple determination (R Square) of earnings
model for men, women and both were 0.596, 0.515 and 0.527, respectively
(see Table 5). These indicated that 51.5 to 59.6 percent of variation in
the earnings could be explained by the variations of variables included
in each model. Furthermore, significant test (t-test) for men's
earnings indicated that coefficients of education and years of work
experience had a highly significant t-value (< 0.01). Therefore, the
null hypothesis of education and years of work experience was rejected.
Two additional independent variables, marital status (< 0.1) and
willingness to engage in frequent business trips (< 0.01) were
significant in women's earnings. When combining both men and
women's earnings, coefficients of education and years of work
experience had a highly significant t-value (< 0.01), while marital
status and willingness to engage in frequent business trip were
significant at < 0.05, all with expected signs. Job satisfaction,
weekly hours spent at work at the office and at home, and gender itself
had no significant influence on earnings.
DISCUSSION
This study found that years of education and work experience,
marital status and willingness to engage in frequent business trips were
crucial factors in determining the managerial earnings of both men and
women. Years of education and work experience positively affected
earnings. Marital status and willingness to engage in frequent business
trips seemed to have more effect on women's earnings, as these
variables were insignificant under men's earnings. When marital
status was coded as 0 for married and 1 for single persons, the negative
coefficient indicated that single women earned less than married women.
This might be because married persons strive to earn more to support
their families. The result contradicts what generally is found in the
USA, i.e., that married women earned less than singles due to high
effort for childcare and household production (Becker, 1985).
The willingness to engage in frequent business trips directly
affected women's earnings. Willingness to accept frequent business
trips was more likely to enhance women manager's earnings. This
frequent business trip factor may reflect that workers have different
tastes or job preferences, because it was not a significant factor in
estimating men's earnings. If frequent business trips become an
issue for women, then the exercise of their preference may result in
lower earnings than men.
Table 6 further displays the independent sample test results about
differences in group means of earnings between men and women. The
equality hypothesis was accepted. It appeared that gender had no
significant effect on earnings. Gender was not a significant factor in
determining manager's earnings in this study. This may be due to
job characteristics and not the individual characteristics that
determine earnings. The introduction of job characteristics such as
frequent business trip to the earning function reduces the male-female
earning inequality. Moreover, responsibilities and effort required in
managerial positions are the same regardless of gender. A human resource
management approach, therefore bases pay on the job requirements, rather
than individual characteristics. Furthermore, there was no statistical
difference in means between men and women managers in terms of
education, years of work experience, number of hours at work and
willingness to engage in frequent business trips.
CONTRIBUTIONS
This paper makes three important contributions in the literature on
gender effect on earnings inequality. First, no existing research has
studied earnings inequality at management level in Thailand. By
controlling for similar observable dimensions, such as management level,
educational attainment, work experience and race, it demonstrates that
gender is not a significant factor in earnings inequality. Second, a
newly created job preference factor, such as frequent business trips,
was a significant factor in the women's earnings model. The
introduction of job characteristics such as frequent business trips to
the earning function reduces the male-female earning inequality. On the
other hand, the exercise of this preference may contribute to lower
earnings for women. Third, the results of testing for equality of means
between men and women managers showed that the two populations were
indifferent in terms of earnings, educational attainment, years of work
experience, work hours at office and willingness to engage in frequent
business trips. However, men and women managers were significantly
different in terms of marital status, job satisfaction and hours work at
home.
PRACTICAL IMPLICATIONS
For practical implication, a semi-logarithm of monthly
manager's earnings (LnY) was estimated. Table 7 relates the
predicted log on earnings to the independent variables, so that their
coefficients can be expressed in percentage terms. Several studies
(Becker & Chiswick, 1966; Mincer, 1974; Hanoch, 1967) estimated the
rate of return to education in this fashion. For example, the education
coefficient of 0.185 men's earnings (Model 4) indicated an 18.5
percent internal rate of return. If men increase education by 1 year,
their earnings will increase by 18.5 percent. The education coefficient
of women's earnings (Model 5) was 0.178 reflecting a 0.7 percent
return below their male counterparts. In Beker's work (1975), the
estimated rate of return in 1939, 1949 and 1958 was 14.5, 13.0 and 14.8
percent, respectively. Angrist and Krueger (1991) found a rate of return
of 8 percent in 1980. A more recent study by Kane and Rouse (1995)
reported a 9 percent rate of return for higher education in 1986.
However, work experience coefficients of men and women's
earnings were 0.046 and 0.048, respectively. An increase in one year
work experience among men will result in 4.6 percent higher in earnings.
Women had slight advantage of 0.2 percent over men at 4.8 percent. In
the USA, Duncan and Hoffman (1979) reported that the rate of return to a
year of experience was between 5.4-8.5percent. Rosen (1982), using the
same data set, found that after correcting for inflation, the real
return on investment in on-the-job training (OJT) as measured by
experience for college graduates was 12.6 percent and for non-college
graduates was 19 percent. Groot and Mekkelholt (1995) employed a 1985
labor market survey of the Organization of Strategic Labor Market
Research in the Netherlands with subset of male wage earners (1,339
observations). They discovered that the rate of return to OJT increased
with the level of education. The rate of return to OJT for the least
educated workers was 13 percent. At the intermediate level the rate of
return to OJT was 36 percent, while at the highest education levels the
rate of return to OJT was over 80 percent.
As found in Table 3, women managers overall spent more time than
men taking care of domestic chores (9.83 VS 6.43 hours) and have less
job satisfaction (0.69 VS 0.81). In particular, married women spent
17.94 hours as compared to 9.99 hours for married men on average to take
care of work at home. This finding suggests more support for women as
described below.
POLICY IMPLICATIONS
Improvements in women's labor work status coexists with
deterioration in their relative economic well-being such as inhibiting
fertility and dissolving marriage (Smith and Ward, 1989). Balancing
efforts in the labor market and the family should be taken into account
in formulating public policy on women's issues. In particular,
policies should address how well they promote gender equity in the work
force and what impact they will have on family. Nevertheless, it is
imperative to address important policy implications of this result for
business in the developing countries. In general, there appears to be a
need to combine two types of policy action for women that promote
progressive social change (Beneria, 2003). The first is a focus on the
transformation of gender relations with policies that will enhance
gender equality. These policies and actions can rely on a wide range of
possibilities, from educational policies to the many dimensions of
cultural transformation. Secondly, more structural policies aimed at
socioeconomic change and the promotion of development models capable of
incorporating progressive social change should be an integral part of
this transformation. Both types of policy can complement each other and
are interconnected in the organizational culture.
Our findings in this study provide a rationale for policy makers to
encourage business organizations to support women managers, especially
the married. O'Neill (2003) examined the trends and reasons of the
gender-gap in wages in the United States. Gender gap was largely due to
non-discriminatory factors that were unlikely to change unless the roles
of men and women in the home become more nearly identical. The dual role
of women workers in Thai society should be recognized and every effort
should be taken to facilitate women's contributions. Flexible
working schedules and management practices, in-plant childcare
nurseries, daycare operations and other nontraditional benefits are some
examples found in a conventional work setting. A study by a
multinational corporation showed that the rate of turnover in management
position was two and a half times higher among top performing women than
it was among men. A large producer of consumer goods reported that one
half of the women who took maternity leave return to their jobs late or
not at all (Schwartz, 1989). Thus, it is important to provide support
for women who want to both raise children and pursue a career, and to
promote women's freedom to pursue a career and a family.
Also noteworthy are the advances in technology that continue to
increase competition in the job market. Automated technology enhances a
firm's ability to accommodate employees in a non-conventional work
setting, such as working from home. Thai business organizations should
embrace the idea of flexible work schedules, including allowing
employees to do some work from home. Women should equip themselves with
computer skills and communication technologies to fully utilize
home-based work environments. With these non-conventional work
opportunities, government and business organizations should emphasize
the importance of education and training in dealing with the highly
competitive, global business, and provide financial and technical
support to women. Equality in education is a necessary, but
insufficient, condition to couteract gender-based and other forms of
inequality due to discriminatory practices. Anti-discriminatory policies
must also be implemented.
CONCLUSIONS
Much of the earnings inequality literature has attempted to
evaluate the impact of gender on earnings. This paper investigated the
gender effect on earnings inequality at the administrative and
managerial level in the private sector of Thailand. Factors that are
important in explaining earnings inequality were explored. Contradictory
to the popular findings, this study found no gender influence on
earnings and no earnings inequality between men and women managers in
Thailand. An avenue for further research might be to investigate other
dimensions of gender inequality that likely exist in hiring, promotion
and training. In addition, there is room for future research to include
studies in other countries for generalization of these results. Such
research will contribute significantly toward our understanding of the
perceived value of human capital in different organizational cultures.
Note: The authors acknowledge financial support from National
Research Council of Thailand. The authors wish to thank Journal Editor,
referees and their colleagues for comments on the earlier draft.
REFERENCES
Angrist, J.D. & Alan B. Krueger (1991). Does compulsory school
attendance affect schooling and earnings? Quarterly Journal of
Economics, November, 979-1014.
Becker, Gary S. (1985). Human capital, effort, and the sexual
division of labor. Journal of Labor Economics, January, 33-58.
Becker, Gary S. (1975). Human capital, New York: National Bureau of
Economic Research.
Becker, Gary S. & B.R. Chiswick (1966). Education and the
distribution of earnings. American Economic Review, 56, 358-369.
Beneria, Lourdes (2003). Gender, development and globalization:
economics as if people mattered, New York, NY: Routledge.
Blau, F. and L.F. Kahn (1997). Swimming upstream: trends in gender
wage differential in the 1980s. Journal of Labor Economics, 15, 1-42.
Borjas (2000). Labor Economics, Crawfordsville: Irwin-McGraw-Hill
Duncan, G. & Hoffman, J. (1979). On-the-job training and
earning differences by race and sex, The Review of Economics and
Statistics, 61, 594-603.
England, P., G. Farkas, B.S. Kilbourne & T. Dou (1998).
Explaining occupational sex segregation and wages: findings from a model
with fixed effects. American Sociological Review, 53, 544-558.
Gronau, Reuben (1988). Sex-related wage differentials and
women's interrupted labor careers-the chicken or the egg. Journal
of Labor Economics, 6, 277-301.
Groot, Wim & Eddie Mekkelholt (1995). The rate of return to
investments in on-the-job training, Applied Economics, 27 (2), 173-181.
Hamermesh, D. (1977). Economics aspects of job satisfaction. In
O.Ashenfelter and W.Oates (Eds), Essays in Labor market analysis. New
York: John Wiley & Sons.
Hanoch, Giora (1967). An economic analysis of earning and
schooling, Journal of Human Resources, 2, 310-329.
Hill, Martha S. (1983). Pattern of time use. In F. Thomas Juster
& Frank P. Stafford (Eds.), Time, Good, and Well Being. Ann Arbor:
University of Michigan Survey Research Center.
Johnson, Peter, Tia Palermo & Nader Asgary (2002). Effects of
increased literacy on wages in manufacturing: an international study,
Proceedings of the Academy for Economics and Economic Education.
Kane, T. J. & Rouse, C. (1995). Labor market returns to two-and
four-year colleges. American Economic Review, June, 600-613.
Macpherson, D. & B.T. Hirsch (1995). Wages and gender
composition: why do women's job pay less? Journal of Labor
Economics, 13, 426-471.
Michael, Robert T. (1973). Education in non market Production. The
Journal of Political Economy, 81, 306-327.
Mincer, J. (1974). Schooling, Experience, and Earnings, New York:
Columbia University.
Naderi, A. & J. Mace (2003). Education and earnings: a
multilevel analysis (a case study of the manufacturing sector in Iran),
Economics of Education Review, 22, 143-156.
Neumark, David (1995). Sex discrimination and women's labor
market outcomes. Journal of Human Resources, 30, 713-740.
O'Neill, June (2003). The gender gap in wages, circa 2000.
American Economic Review, 93 (2), 309-314.
O'Neill, J. & S. Polachek (1993). Why the gender gap in
wages narrowed in the 1980s. Journal of Labor Economics, 11, 205-228.
Polachek, S.W. (1981). Occupational self selection: a human capital
approach to sex differences in occupational structure. Review of
Economics and Statistics, 63, 60-69.
Rosen, H. S. (1982). Taxation and on-the-job training decisions,
The Review of Economics and Statistics, 64, 442-449.
Schumann, Paul L.; Dennis A. Ahlburg & Christine Brown Mahoney
(1994). The effects of human capital and job characteristics on pay.
Journal of Human Resources, Spring, 29 (2), 481-503.
Schwartz, Felice N. (1989). Management women and the new facts of
life. Harvard Business Review, January-February, 65-79.
Smith, James P., & Michael Ward (1989). Women in the labor
market and in the family. The Journal of Economic Perspectives, 3 (1),
9-23.
Tantatape Brahmasrene, Purdue University North Central Ruangthong
Chaiprasop, Ramkhamhaeng University, Thailand
Table 1: Thailand Labor Force Survey
Selected Categories by Gender
Year 1996
Gender Male Female
Labor force in millions (percent) 17.2 (57.34) 12.8 (42.66)
Administrative, Managerial & Professional Workers
Urban Area (percent) 170,850 (50.3) 168,700 (49.7)
Rural Area (percent) 82,400 (44.7) 101,800 (55.3)
Year 2000
Gender Male Female
Labor force in millions (percent) 17.4 (57.24) 13.0 (42.76)
Administrative, Managerial & Professional Workers
Urban Area (percent) 248,600 (43.2) 326,200 (56.8)
Rural Area (percent) 96,100 (40.7) 139,800 (59.3)
Year 1994 N/A
Avg. Monthly Earnings (Baht) of College Graduates
Urban Area 10,192 9,662
Rural Area 9,618 8,390
Avg. Weekly Hour Work of College Graduates
Urban Area 38.6 37.9
Rural Area 38.6 37.9
Source: Thai National Statistical Office
Table 2: Description of Variables
Dependent variables
Y Monthly earnings
LnY Natural logarithm of monthly earnings
Human capital variables
ED Years of education
WORK Years of work experience
Worker characteristics
MSTATUS Marital status: 0 = married, 1 = otherwise
HRWORK Weekly hours work at the office
HRHOME Weekly hours work at home
GENDER 0 = Men, 1 = Women
Working conditions
JOBSAT Job satisfaction: 0 = unsatisfied to unsure, 1 = satisfied
FREQUENT Willingness to engage in business trip frequently: 0 = No,
1 = Yes
Table 3: Subpopulations Differences
Gender Mstatus Y Ed
Men .00 24,747.7273 16.4667
1.00 16,470.0000 16.1667
Total 20,372.3571 16.3030
Women .00 24,849.0789 16.0000
1.00 15,978.9024 15.7595
Total 18,787.7917 15.8333
Total .00 24,801.9718 16.2154
1.00 16,131.5966 15.8870
Total 19,371.5789 16.0056
Mstatus Work Jobsat Hrwork
.00 9.2059 .9062 45.7000
1.00 4.7462 .7250 43.9630
Total 6.8233 .8056 44.7620
.00 9.3925 .8250 46.4406
1.00 4.8027 .6235 45.8306
Total 6.3200 .6880 46.0383
.00 9.3068 .8611 46.1309
1.00 4.7843 .6560 45.2640
Total 6.5094 .7310 45.5951
Mstatus Hrhome Frequent
.00 9.9853 .7187
1.00 3.4075 .6000
Total 6.4297 .6528
.00 17.9359 .3750
1.00 6.1059 .6353
Total 9.8266 .5520
.00 14.2329 .5278
1.00 5.2424 .6240
Total 8.5571 .5888
Note Marital status: 0 = married, 1 = otherwise
Table 4: Correlations
Y Edu Work
Y 1 .285(**) .371(**)
EDU .285(**) 1 -.042
WORK .371(**) -.042 1
MSTATUS -.305(**) -.173(*) -.389(**)
JOBSAT .122 -.051 .171(*)
HRWORK .028 -.004 .023
HRHOME .157 -.038 .187(*)
FREQUENT .052 .079 -.096
GENDER -.056 -.249(**) -.044
Mstatus Jobsat Hrwork
Y -.305(**) .122 .028
EDU -.173(*) -.051 -.004
WORK -.389(**) .171(*) .023
MSTATUS 1 -.223(**) -.050
JOBSAT -.223(**) 1 -.119
HRWORK -.05 -.119 1
HRHOME -.474(**) -.002 .036
FREQUENT .094 -.083 -.008
GENDER .142(*) -.125 .066
Hrhome Frequent Gender
Y .157 .052 -.056
EDU -.038 .079 -.249(**)
WORK .187(*) -.096 -.044
MSTATUS -.474(**) .094 .142(*)
JOBSAT -.002 -.083 -.125
HRWORK .036 -.008 .066
HRHOME 1 -.256(**) .190(*)
FREQUENT -.256(**) 1 -.095
GENDER .190(*) -.095 1
NOTE ** Correlation is significant at the 0.01 level (2-tailed).
* Correlation is significant at the 0.05 level (2-tailed).
Table 5: Earnings Model Coefficients
Coefficients Men
(1) Y VIF
CONSTANT -33856.264 * (-1.743)
ED 2764.699 *** (2.800) 1.376
WORK 900.398 *** (3.288) 1.309
MSTATUS -5747.549 (-1.555) 1.800
JOBSAT 3108.047 (.776) 1.220
HRWORK 107.260 (.714) 1.038
HRHOME -79.442 (-.426) 1.326
FREQUENT 134.501 (.043) 1.095
GENDER
R Square 0.596
F Statistics 6.736 ***
Women
(2) Y VIF
CONSTANT -33638.461 ** (-2.250)
ED 2808.614 *** (3.697) 1.084
WORK 1054.021 *** (4.989) 1.275
MSTATUS -5118.356 * (-1.712) 1.745
JOBSAT 3724.927 (1.332) 1.327
HRWORK -33.708 (-.280) 1.205
HRHOME 55.742 (.584) 1.590
FREQUENT 7099.004 *** (2.796) 1.354
GENDER
R Square 0.515
F Statistics 9.716 ***
Both
(3) Y VIF
CONSTANT -34758.282 *** (-3.018)
ED 2812.594 *** (4.819) 1.162
WORK 952.408 *** (5.943) 1.222
MSTATUS -4820.381 ** (-2.160) 1.700
JOBSAT 3305.612 (1.543) 1.184
HRWORK -3.100 (-.035) 1.082
HRHOME 25.588 (.318) 1.519
FREQUENT 4532.556 ** (2.437) 1.173
GENDER 2244.466 (1.182) 1.168
R Square 0.527
F Statistics 14.344 ***
Notes t statistics are in parentheses. Significant
level : * 0.10, ** 0.05, *** 0.01
VIF = Variance inflation factor, a measure of collinearity
Table 6: Independent Samples Test
Variables Variances Assumed Levene's Test for Equality
of Variances
F Sig.
Y Equal .260 .611
Not Equal
ED Equal .169 .681
Not Equal
WORK Equal 1.568 .212
Not Equal
MSTATUS Equal 9.86 .002
Not Equal
JOBSAT Equal 14.415 .000
Not Equal
HRWORK Equal .007 .932
Not Equal
HRHOME Equal 4.989 .027
Not Equal
FREQUENT Equal 7.725 .006
Not Equal
Variances t-test for Equality of Means
Assumed t Sig. (2-tailed)
Equal .764 .446
Not Equal .793 .429
Equal 1.287 .200
Not Equal 1.249 .214
Equal .617 .538
Not Equal .610 .543
Equal -2.019 .045
Not Equal -1.981 .049
Equal 1.764 .079
Not Equal 1.839 .068
Equal -1.035 .302
Not Equal -1.070 .287
Equal -2.201 .029
Not Equal -2.424 .017
Equal 1.338 .183
Not Equal 1.352 .178
Table 7: Model Coefficients for Natural Logarithm Of Monthly Earnings
Coefficients Men
(4) LnY VIF
CONSTANT 6.087 *** (7.063)
ED .185 *** (4.229) 1.376
WORK .046 *** (3.762) 1.309
MSTATUS -.212 (-1.291) 1.800
JOBSAT .216 (1.213) 1.220
HRWORK .009 (1.307) 1.038
HRHOME -.003 (-.328) 1.326
FREQUENT -.084 (-.602) 1.095
GENDER
R Square 0.685
F Statistics 9.930 ***
Coefficients Women
(5) LnY VIF
CONSTANT 6.536 *** (9.399)
ED .178 *** (5.032) 1.084
WORK .048 *** (4.884) 1.275
MSTATUS -.223 (-1.600) 1.745
JOBSAT .090 (.690) 1.327
HRWORK .000 (-.009) 1.205
HRHOME .004 (.794) 1.590
FREQUENT .190 (1.605) 1.354
GENDER
R Square 0.515
F Statistics 9.716 ***
Coefficients Both
(6) LnY VIF
CONSTANT 6.346 *** (12.034)
ED .180 *** (6.750) 1.162
WORK .044 *** (6.046) 1.222
MSTATUS -.208 ** (-2.035) 1.700
JOBSAT .123 (1.250) 1.184
HRWORK .003 (.632) 1.082
HRHOME .002 (.573) 1.519
FREQUENT .106 (1.245) 1.173
GENDER .082 (.943) 1.168
R Square 0.590
F Statistics 18.520 ***
Notes t statistics are in parentheses.
Significant level : * 0.10, ** 0.05, *** 0.01
VIF = Variance inflation factor, a measure of collinearity