Econ 107 LAB Session: Week1

Ran Wang

About Me

TA: Ran Wang

Email: rwang022@ucr.edu

Office hours: Friday 10:00AM-12:00PM at Sproul Hall 3125

Several Important Things

In class assignment (every two weeks)

Email subject: Econ 107+Assignment name+your name+your student id

Example: Econ 107_Assignment 1_Ran Wang_ID:861199999

Assignment email: econ107lab@gmail.com

Questions email: rwang022@ucr.edu

Intro to Stata

Stata is a data analysis and statistical software created in 1985 by StataCorp. Most of its users work in research, especially in the fields of economics, sociology, political science, biomedicine and epidemiology.

Stata's capabilities include data management, statistical analysis, graphics, simulations, regression, and custom programming.

Intro to Stata

Intro to Stata

Stata command:

Example: Sample Mean

clear
set obs 1000
gen x =rnormal(0,1)
mean x
histogram x

Intro to Stata

Stata command:

Do-file: run all the commands automatically

Question Part

Download Data: CPS92_08

It contains data on full-time, full-year workers, age 25-34, with a high school diploma or BA/BS as their highest degree.

  • ( a ) Compute the sample mean for average hourly earnings (AHE) in 1992 and 2008. Construct a 95% condence interval for the population means of AHE in 1992 and 2008 and the change between 1992 and 2008.

  • ( b ) In 2008, the value of the Consumer Price Index (CPI) was 215.2. In 1992, the value of the CPI was 140.3. Repeat (a) but use AHE measured in real 2008 dollars; that is, adjust the 1992 data for the price ination that occurred between 1992 and 2008.

Question Part

  • ( c ) If you were interested in the change in workerspurchasing power from 1992 to 2008, would you use the results from (a) or from (b)? Explain.

  • ( d ) Use the 2008 data to construct a 95% condence interval for the mean of AHE for high school graduates. Construct a 95% condence interval for the mean of AHE for workers with a college degree. Construct a 95% condence interval for the difference between the two means.

  • ( e ) Repeat (d) using the 1992 data expressed in real 2008 dollars.

Question Part

  • ( f ) Did real wages of high school graduates increase from 1992 to 2008? Explain. Did real wages of college graduates increase? Did the gap between earnings of college and high school graduates increase? Explain, using appropriate estimates, condence intervals, and test statistics.