Table 1: Description of
Variables
(Note:
This analysis is for men only)
|
Variable
Name |
Description |
|
Lnwage |
The
log of wages. Lnwage=ln(wage) |
|
Wage_re |
Wage
in $ per hour (not used in this analysis) |
|
Asian,
Black, Hispanic |
1
if the respondent is in that race/ethnic group, 0 otherwise (Non-Hispanic
white (“white” ) is the excluded category) |
|
Years
of Education |
The
respondent’s years of education |
|
(group-name)*Edyrs |
The
interaction term between the race/ethnic group and education (in
Stata, the result of including the term i.re*edyrs, where “re” is the categorical variable for
race/ethnicity) |
(Note:
When discussing differences in log wages, you can call them “log points”. Using
log wages is useful because we are estimating proportional differences in wages.
For
example ln(10)-ln(5) = ln(2) – ln(1) because
10/5 = 2 = 2/1
ln(10) = 2.302
ln(5) = 1.609
ln(2)=.693
ln(1)=0
If
you doubled everyone’s wage, the results for the gender gap using log wages
would not change.)
Table 2: Summary Statistics,
by Race/Ethnicity
(The mean of lnwage and edyrs for each
race/ethnic group)
Ignore the column
“weight”
. by re: sum lnwage wage_re edyrs [w=weight]
-------------------------------------------------------------------------------
-> re = white
(analytic weights assumed)
Variable | Obs Weight Mean Std. Dev. Min Max
-------------+-----------------------------------------------------------------
lnwage | 44133 87748824.8 2.847951 .593882 .9618849 5.318708
wage_re | 44133 87748824.8 20.58432 13.11469 2.616624 204.12
edyrs | 44133 87748824.8 13.80586 2.725675 1 21
-------------------------------------------------------------------------------
-> re = black
Variable | Obs Weight Mean Std. Dev. Min Max
-------------+-----------------------------------------------------------------
lnwage | 3383 9538143.66 2.587464 .5316631 1.021423 5.230694
wage_re | 3383 9538143.66 15.43376 9.603858 2.777143 186.9224
edyrs | 3383 9538143.66 13.18191 2.301107 1 21
-------------------------------------------------------------------------------
-> re = asian
Variable | Obs Weight Mean Std. Dev. Min Max
-------------+-----------------------------------------------------------------
lnwage | 1905 4701733.92 2.918734 .6587708 1.175573 5.125326
wage_re | 1905 4701733.92 22.91397 15.92213 3.24 168.2289
edyrs | 1905 4701733.92 15.11951 3.267622 1 21
-------------------------------------------------------------------------------
-> re = hispanic
Variable | Obs Weight Mean Std. Dev. Min Max
-------------+-----------------------------------------------------------------
lnwage | 4637 13299069 2.407758 .4745804 1.013054 4.537548
wage_re | 4637 13299069 12.60776 7.619075 2.754 93.46136
edyrs | 4637 13299069 10.21205 3.737197 1 21
Table 3: Regression
Estimates of Race and Ethnic Inequality for Men, 2005 Current Population Survey
|
|
(1) |
(2) |
(3) |
|
|
lnwage |
Lnwage |
lnwage |
|
Black |
-0.260 |
-0.202 |
-0.168 |
|
|
(0.009)** |
(0.008)** |
(0.046)** |
|
Asian
|
0.071 |
-0.053 |
-0.173 |
|
|
(0.013)** |
(0.011)** |
(0.053)** |
|
Hispanic |
-0.440 |
-0.103 |
0.567 |
|
|
(0.008)** |
(0.008)** |
(0.023)** |
|
Years
of education |
|
0.094 |
0.106 |
|
|
|
(0.001)** |
(0.001)** |
|
(Black)*Edyrs |
|
|
-0.002 |
|
|
|
|
(0.003) |
|
(Asian)*Edyrs |
|
|
0.007 |
|
|
|
|
(0.003)* |
|
(Hispanic)*Edyrs |
|
|
-0.061 |
|
|
|
|
(0.002)** |
|
Constant |
2.848 |
1.552 |
1.388 |
|
|
(0.003)** |
(0.011)** |
(0.013)** |
|
Observations |
54058 |
54058 |
54058 |
|
R-squared |
0.07 |
0.26 |
0.28 |
Standard
errors in parentheses
*
significant at 5%; ** significant at 1%
1. a. How does the
coefficient on the variable “Asian” in Model 1 of Table 3 relate to the average
values of lnwage by race and ethnicity listed in
Table 2? [I.e., if you only had Table 2
you could tell me what the results of Model 1 of Table 3 would be (but not the
other models)….why?]
b. What is the 80%
confidence interval for the coefficient on Asian in Model 1 in Table 3? [You
can use the standard normal distribution rather than the t-distribution because
the number of cases is large. If the
z-score is between two numbers, choose the closest one.]
2. Test the hypothesis that the coefficient on Asian
in Model 1 equals 0.05,
3. Explain why the coefficient on Asian has a
positive effect in Model 1 and a negative effect in Model 2. How
could you argue that the coefficient on Asian in Model 2 is measuring the
effect of discrimination in the labor market?
What information from Table 2 is useful in understanding what happens to
the coefficient on Asian going from Model 1 to Model 2 of Table 3?
4. a) In Model 3, what
is the size of the predicted wage gap (in terms of log wages) between white and
Hispanic men with 12 years of education? (I.e., what is the predicted
difference in log wages for a white man with 12 years of education and a
Hispanic man with 12 years of education?)
b) In Model 3, does the
size of the wage gap (in
terms of log wages) between white and Hispanic men get bigger or smaller as the
number of years of education increases?