STA442/1008 Assignment 3

Quiz on Friday Oct. 14th

This assignment is based on Chapter 2 of the class notes and associated lecture material. You will do the job described below, and bring your log file and your list file to the quiz. Then you will be asked a few   very simple questions, like what's the mean number of hours of sports programming watched per household, or how many households in the sample do not have a TV. The answers will all be numerical, and they will all be directly from your printout. The quiz will consist of your circling a few numbers and writing a few words on your printouts, and turning them in. It should only take a few minutes.

The file tv1.dat contains data from a 1982 survey conducted in Stevens County in the United States. At the time, Stevens County was divided into 75 districts including rural, small-town and urban areas. For each of 500 households interviewed, the data file contains district number, household number within district, assessed value of home in US dollars (an indirect measure of income, which was not asked), and answers to 9 questions related to the respondents' interest in getting cable TV. The variables are:

1. District: 1-25 are rural, 26-50 small town, 51-75 city.
2. Household (numbered within district)
3. Assessed value of home in US dollars
4. Number of persons 12 and older in household
5. Number of persons 11 and younger in household
6. Number of TV sets in Household
7. Price willing to pay for cable TV
8. Total TV hours watched last week (add hours for all persons in household)
9. Hours Public Affairs watched last week
10. Hours Sports watched last week
11. Hours Children's programming watched last week
12. Hours Movies watched last week

You can get a copy of the data file here, but the file is pretty long, and copy-paste with the mouse might not be the way to go. One thing you might try is to make your browser download the page "source," which in this case is just the file itself.

Here's what you do

Write a SAS program that reads the data and labels the variables with the label statement. Create a new variable with 3 values: Rural, Small Town and City. Use proc means to obtain n, mean and standard deviation for all the quantitative variables.Use proc freq to obtain frequency distributions of all the categorical variables, including the quantitative variables that take on just a few values. That's it.

For debugging, your initial run should include frequency distributions of District and Household for data cleaning. But once the data are cleaned, you should omit these, because printing them is a waste of paper.

Bring your log file and your list file to the quiz. You will hand both of them in. Here are a few suggestions and comments:

• Make sure your name is written on both your log file and your list file. Do not write anything else on the printouts before the quiz.
• Make sure the printouts are complete. It is smart to staple the pages together.
• You could get zero marks for the quiz if there are any error messages on your log file. Substantial marks will be deducted if there are warnings. Error messages mean there is something wrong, and it needs to be fixed before you proceed to statistical analysis. Usually, warnings indicate something wrong too, though in some cases you can tolerate warnings if you know why SAS is warning you and you are satisfied with the action it takes. But for this assignment, the rule is clear: No errors and no warnings.
• You must be absolutely sure that the log file and list file come from the same run. For me to check your work, the program on your log file must be exactly the program that generated your statistical output.
• This all sounds intimidating, but the objective is to keep you from losing a lot of marks for "samll" mistakes that are actually big -- and avoidable.
• Of course you may edit the data file.
• Don't delete your program; later assignments will build on it.