Variable
Coefficients
p-value
Variable Definition
Sample Mean
Intercept
12.48
0.000
YEARS
0.012
0.023
# of years employed at UofA
16.4
AGE
0.011
0.355
Age of professor in years
56.6
AGESQ
-0.007
0.201
Age Squared
3,280
FEMALE
-0.041
0.132
=1 if Female
0.240
HISPANIC
-0.011
0.543
=1 if Hispanic
0.067
MEDICINE
0.426
0.000
=1 if in medical school
0.385
A cross-sectional sample of 104 UofA full professors was taken in 2011. A regression was run using the dependent variable, LSAL, the natural logarithm of the professors' salaries. The unconditional mean of salary is $153,959; the unconditional mean of log of salary is 11.87. The results of the regression are given below
Use the above information to answer the following questions
a. How do you interpret the coefficient on MEDICINE? Explain using full sentences.
b. Do female full professors earn lower salaries on average? Be sure to explain your reasoning.
c. Show in detail how you would calculate the marginal effect of YEARS on salary?
d. What does the sample mean of HISPANIC indicate? What are the units of measure of this variable? Explain.
e. How would you improve this model?
| Variable | Coefficients | p-value | Variable Definition | Sample Mean |
| Intercept | 12.48 | 0.000 | ||
| YEARS | 0.012 | 0.023 | # of years employed at UofA | 16.4 |
| AGE | 0.011 | 0.355 | Age of professor in years | 56.6 |
| AGESQ | -0.007 | 0.201 | Age Squared | 3,280 |
| FEMALE | -0.041 | 0.132 | =1 if Female | 0.240 |
| HISPANIC | -0.011 | 0.543 | =1 if Hispanic | 0.067 |
| MEDICINE | 0.426 | 0.000 | =1 if in medical school | 0.385 |
A cross-sectional sample of 104 UofA full professors was taken in 2011. A regression was run using the dependent variable, LSAL, the natural logarithm of the professors' salaries. The unconditional mean of salary is $153,959; the unconditional mean of log of salary is 11.87. The results of the regression are given below
Use the above information to answer the following questions
a. How do you interpret the coefficient on MEDICINE? Explain using full sentences.
b. Do female full professors earn lower salaries on average? Be sure to explain your reasoning.
c. Show in detail how you would calculate the marginal effect of YEARS on salary?
d. What does the sample mean of HISPANIC indicate? What are the units of measure of this variable? Explain.
e. How would you improve this model?
