Read the box “the Return to Education and the Gender Gap” in Section 8.3. a) Consider a male with 16 years of education and 2 years of experience. Use the results from column (4) of Table 8.1 and the method in Key Concept 8.1. to estimate the expected change in the logarithm of average hourly earnings (AHE) associated with an additional year of experience.  b) Explain why your answer to (a) does not depend on the region he is from. c) Repeat (a), assuming 10 years of experience. d) Explain why the answers to (a) and (b) are different. e) Is the difference in the answers to (a) and (b) statistically significant at the 5% level? Explain.  f) Would your answers to (a) through (d) change if the person were female? Explain.  g) How would you change the regression if you suspected that the effect of experience on earnings was different for men than for women?

MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
icon
Related questions
Question

Read the box “the Return to Education and the Gender Gap” in Section 8.3.

a) Consider a male with 16 years of education and 2 years of experience. Use the results from column (4) of Table 8.1 and the method in Key Concept 8.1. to estimate the expected change in the logarithm of average hourly earnings (AHE) associated with an additional year of experience. 

b) Explain why your answer to (a) does not depend on the region he is from.

c) Repeat (a), assuming 10 years of experience.

d) Explain why the answers to (a) and (b) are different.

e) Is the difference in the answers to (a) and (b) statistically significant at the 5% level? Explain. 

f) Would your answers to (a) through (d) change if the person were female? Explain. 

g) How would you change the regression if you suspected that the effect of experience on earnings was different for men than for women?

The Return to Education and the Gender Gap
n addition to its intellectual pleasures, education
has economic rewards. As the boxes in Chapters 3
and 5 show, workers with more education tend to
earn more than their counterparts with less education.
The analysis in those boxes was incomplete, however,
for at least three reasons. First, it failed to control for
other determinants of earnings that might be cor-
related with educational achievement, so the OLS
estimator of the coefficient on education could have
omitted variable bias. Second, the functional form
used in Chapter 5-a simple linear relation-implies
that earnings change by a constant dollar amount for
each additional year of education, whereas one might
suspect that the dollar change in earnings is actually
larger at higher levels of education. Third, the box
in Chapter 5 ignores the sex differences in earnings
highlighted in the box in Chapter 3.
These limitations can be addressed by a multiple
regression analysis that controls for determinants of
earnings that, if omitted, could cause omitted vari-
able bias and that uses a nonlinear functional form
relating education and earnings. Table 8.1 summa-
rizes regressions estimated using data on full-time
workers, ages 30 through 64, from the Current Popu-
lation Survey (the CPS data are described in Appen-
dix 3.1). The dependent variable is the logarithm
of hourly earnings, so another year of education is
associated with a constant percentage increase (not
a dollar increase) in earnings.
Table 8.1 has four salient results. First, the omission
of sex in regression (1) does not result in substantial
omitted variable bias: Even though sex enters regres-
sion (2) significantly and with a large coefficient, sex
and years of education are nearly uncorrelated: On
average, men and women have nearly the same lev-
els of education. Second, the returns to education are
economically and statistically significantly different
for men and women: In regression (3), the t-statistic
testing the hypothesis that they are the same is 3.42
(= 0.006/0.0018). As the tight confidence intervals
attest, the return to education is precisely estimated
both for men and for women. Third, regression (4)
controls for the region of the country in which the
individual lives, thereby addressing potential omitted
variable bias that might arise if years of education
differ systematically by region. Controlling for region
makes a small difference to the estimated coefficients
on the education terms relative to those reported in
regression (3). Fourth, regression (4) controls for the
potential experience of the worker, as measured by
years since completion of schooling. The estimated
coefficients imply a declining marginal value for each
year of potential experience.
200
The estimated economic return to education in
regression (4) is 11.14% for each year of education
for men and 11.96% (= 0.1114 + 0.0082, in percent)
for women. Because the regression functions for
men and women have different slopes, the gender
gap depends on the years of education. For 12
years of education, the gender gap is estimated to
be 27.0% (= 0.0082 x 12 0.368, in percent);
for 16 years of education, the gender gap is less in
percentage terms, 23.7%.
These estimates of the return to education and
the gender gap still have limitations, including the
possibility of other omitted variables, notably the
native ability of the worker, and potential problems
associated with the way variables are measured in
the CPS. Nevertheless, the estimates in Table 8.1 are
consistent with those obtained by economists who
carefully address these limitations. A survey by the
econometrician David Card (1999) of dozens of
empirical studies concludes that labor economists'
best estimates of the return to education gener-
ally fall between 8% and 11% and that the return
depends on the quality of the education. If you are
interested in learning more about the economic
return to education, see Card (1999).
Transcribed Image Text:The Return to Education and the Gender Gap n addition to its intellectual pleasures, education has economic rewards. As the boxes in Chapters 3 and 5 show, workers with more education tend to earn more than their counterparts with less education. The analysis in those boxes was incomplete, however, for at least three reasons. First, it failed to control for other determinants of earnings that might be cor- related with educational achievement, so the OLS estimator of the coefficient on education could have omitted variable bias. Second, the functional form used in Chapter 5-a simple linear relation-implies that earnings change by a constant dollar amount for each additional year of education, whereas one might suspect that the dollar change in earnings is actually larger at higher levels of education. Third, the box in Chapter 5 ignores the sex differences in earnings highlighted in the box in Chapter 3. These limitations can be addressed by a multiple regression analysis that controls for determinants of earnings that, if omitted, could cause omitted vari- able bias and that uses a nonlinear functional form relating education and earnings. Table 8.1 summa- rizes regressions estimated using data on full-time workers, ages 30 through 64, from the Current Popu- lation Survey (the CPS data are described in Appen- dix 3.1). The dependent variable is the logarithm of hourly earnings, so another year of education is associated with a constant percentage increase (not a dollar increase) in earnings. Table 8.1 has four salient results. First, the omission of sex in regression (1) does not result in substantial omitted variable bias: Even though sex enters regres- sion (2) significantly and with a large coefficient, sex and years of education are nearly uncorrelated: On average, men and women have nearly the same lev- els of education. Second, the returns to education are economically and statistically significantly different for men and women: In regression (3), the t-statistic testing the hypothesis that they are the same is 3.42 (= 0.006/0.0018). As the tight confidence intervals attest, the return to education is precisely estimated both for men and for women. Third, regression (4) controls for the region of the country in which the individual lives, thereby addressing potential omitted variable bias that might arise if years of education differ systematically by region. Controlling for region makes a small difference to the estimated coefficients on the education terms relative to those reported in regression (3). Fourth, regression (4) controls for the potential experience of the worker, as measured by years since completion of schooling. The estimated coefficients imply a declining marginal value for each year of potential experience. 200 The estimated economic return to education in regression (4) is 11.14% for each year of education for men and 11.96% (= 0.1114 + 0.0082, in percent) for women. Because the regression functions for men and women have different slopes, the gender gap depends on the years of education. For 12 years of education, the gender gap is estimated to be 27.0% (= 0.0082 x 12 0.368, in percent); for 16 years of education, the gender gap is less in percentage terms, 23.7%. These estimates of the return to education and the gender gap still have limitations, including the possibility of other omitted variables, notably the native ability of the worker, and potential problems associated with the way variables are measured in the CPS. Nevertheless, the estimates in Table 8.1 are consistent with those obtained by economists who carefully address these limitations. A survey by the econometrician David Card (1999) of dozens of empirical studies concludes that labor economists' best estimates of the return to education gener- ally fall between 8% and 11% and that the return depends on the quality of the education. If you are interested in learning more about the economic return to education, see Card (1999).
TABLE 8.1
Dependent variable: logarithm of Hourly earnings.
Regressor
(1)
Years of education
Female
Female X Years of education
Potential experience
The Return to Education and the Gender Gap: Regression Results
for the United States in 2015
Potential experience²
R²
a. Regional control variables?
No
95% confidence interval for return to education
Combined men & women
For men
For women
0.1056
(0.0009)
[0.104, 0.107]
0.209
(2)
0.1089
(0.0009)
-0.252
(0.005)
No
[0.107, 0.111]
0.251
(3)
0.1063
(0.0018)
The Expected Change in Y from a Change in X₁
in the Nonlinear Regression Model [Equation (8.3)]
-0.342
(0.026)
0.0063
(0.0018)
No
[0.104, 0.109]
[0.110, 0.115]
0.251
(4)
0.1114
(0.0013)
The expected change in Y, AY, associated with the change in X₁, AX₁, holding
X₂,..., X constant, is the difference between the value of the population regres-
sion function before and after changing X₁, holding X₂, ..., X constant. That is,
the expected change in Y is the difference:
ΔΥ = f(X + ΔΧ, Χ2, Xk) − f(Xí, X2, ..., X).
(8.4)
The estimator of this unknown population difference is the difference between
the predicted values for these two cases. Let (X₁, X₂, ..., X) be the predicted
value of Y based on the estimator f of the population regression function. Then
the predicted change in Y is
AŶ = Ĵ(X₁ + AX₁, X₂, ..., Xk) - Ĵ(X₁, X₂,..., Xk). (8.5)
-0.368
(0.026)
0.0082
(0.0018)
0.0147
(0.0013)
-0.000183
(0.000024)
Yes
[0.109, 0.114]
[0.117, 0.122]
The data are from the March 2016 Current Population Survey (see Appendix 3.1). The sample size is n = 47,233 obser-
vations for each regression. Female is an indicator variable that equals 1 for women and 0 for men. Potential experience
equals the number of years since completion of schooling. The regional control variables included in regression (4) are
Midwest, South, and West which are indicator variables denoting the region of the United States in which the worker
lives (the omitted region is Northeast). Heteroskedasticity-robust standard errors are reported in parentheses below
the estimated coefficients.
0.262
KEY CONCEPT
8.1
Transcribed Image Text:TABLE 8.1 Dependent variable: logarithm of Hourly earnings. Regressor (1) Years of education Female Female X Years of education Potential experience The Return to Education and the Gender Gap: Regression Results for the United States in 2015 Potential experience² R² a. Regional control variables? No 95% confidence interval for return to education Combined men & women For men For women 0.1056 (0.0009) [0.104, 0.107] 0.209 (2) 0.1089 (0.0009) -0.252 (0.005) No [0.107, 0.111] 0.251 (3) 0.1063 (0.0018) The Expected Change in Y from a Change in X₁ in the Nonlinear Regression Model [Equation (8.3)] -0.342 (0.026) 0.0063 (0.0018) No [0.104, 0.109] [0.110, 0.115] 0.251 (4) 0.1114 (0.0013) The expected change in Y, AY, associated with the change in X₁, AX₁, holding X₂,..., X constant, is the difference between the value of the population regres- sion function before and after changing X₁, holding X₂, ..., X constant. That is, the expected change in Y is the difference: ΔΥ = f(X + ΔΧ, Χ2, Xk) − f(Xí, X2, ..., X). (8.4) The estimator of this unknown population difference is the difference between the predicted values for these two cases. Let (X₁, X₂, ..., X) be the predicted value of Y based on the estimator f of the population regression function. Then the predicted change in Y is AŶ = Ĵ(X₁ + AX₁, X₂, ..., Xk) - Ĵ(X₁, X₂,..., Xk). (8.5) -0.368 (0.026) 0.0082 (0.0018) 0.0147 (0.0013) -0.000183 (0.000024) Yes [0.109, 0.114] [0.117, 0.122] The data are from the March 2016 Current Population Survey (see Appendix 3.1). The sample size is n = 47,233 obser- vations for each regression. Female is an indicator variable that equals 1 for women and 0 for men. Potential experience equals the number of years since completion of schooling. The regional control variables included in regression (4) are Midwest, South, and West which are indicator variables denoting the region of the United States in which the worker lives (the omitted region is Northeast). Heteroskedasticity-robust standard errors are reported in parentheses below the estimated coefficients. 0.262 KEY CONCEPT 8.1
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 4 steps with 7 images

Blurred answer
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
MATLAB: An Introduction with Applications
MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc
Probability and Statistics for Engineering and th…
Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning
Statistics for The Behavioral Sciences (MindTap C…
Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning
Elementary Statistics: Picturing the World (7th E…
Elementary Statistics: Picturing the World (7th E…
Statistics
ISBN:
9780134683416
Author:
Ron Larson, Betsy Farber
Publisher:
PEARSON
The Basic Practice of Statistics
The Basic Practice of Statistics
Statistics
ISBN:
9781319042578
Author:
David S. Moore, William I. Notz, Michael A. Fligner
Publisher:
W. H. Freeman
Introduction to the Practice of Statistics
Introduction to the Practice of Statistics
Statistics
ISBN:
9781319013387
Author:
David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:
W. H. Freeman