Introductory Econometrics: A Modern Approach 6th Edition by Jeffrey M Wooldridge

Exercise 3

Use the data in BWGHT.RAW to answer this question.

(i) How many women are in the sample, and how many report smoking during pregnancy?

(ii) What is the average number of cigarettes smoked per day? Is the average a good measure of the “typical” woman in this case? Explain.

(iii) Among women who smoked during pregnancy, what is the average number of cigarettes smoked per day? How does this compare with your answer from part (ii), and why?

(iv) Find the average of fatheduc in the sample. Why are only 1,192 observations usedto compute this average?

(v) Report the average family income and its standard deviation in dollars.

Step 1 of 5

(i)

There are 1,388 observations in the sample. Tabulating the variable cigs shows that 212 women have cigs > 0.