PA 705
Fall 2004

Homework Assignment # 6

Tests of Statistical Significance

due October 27

I. Please do the following problems for Homework and Discussion from ORB: Q2, Q4

II. Lab work: using the 2004 SF Citizen survey

You can find this in the lab on "my computer/data on neptune/Naff", or on the Class web page

Please include your output when you turn in the homework.

1. Choose a variable measured at the ordinal level (Q1-16) and one of the demographic variables (under General Information).
    

   1. State a hypothesis specifying the relationship you expect to find between these variables (it should be a comparison of means).
       

   2. State the null hypothesis
       

   3. Choose an alpha level and explain why you chose that particular level.
       

   4. Run the appropriate statistical test to test your hypothesis.
       

   5. Report the results.
      
       
2. We know that in the past the the overall job rating San Franciscans have given to local government service provision (see Q16 on survey) is 4.0 (representing "poor" on the 5 point scale). The mayor wants to know whether the sample of citizens surveyed this year show improvement in ratings.
    
   1. Choose the appropriate statistical test to determine if the sample mean represents a significant difference from the mean of 4.0.
       
   2. What alpha level will you use and why?
       
   3. Report the results.
      
       
3. Choose two variables that are measured at the nominal level. (I suggest that you choose them such that you have no more than 9 cells). Be
    
   1. State a hypothesis describing the relationship you expect to find between these variables
       
   2. Run the appropriate statistical test to test your hypothesis at the p<.05 level.
       
   3. Report the results in terms of column percentages,  statistical significance and "practical" significance.