Exercise 9. Candidate character and presidential vote
Another reason for using three-variable tables in our data analysis is to examine the joint influence of two independent variables on a dependent variable. To illustrate this situation, we can consider the influence of how perceptions of candidate personal characteristics influence the vote. Specifically, we can look at how voters perceived the leadership abilities of Bush and Kerry. This dataset contains several items of information about the perceptions of the personal characteristics of the two presidential candidates, including questions that asked the respondents whether or not they thought that Bush and Kerry were strong leaders (V035 and V042).
To begin, you should generate a table that shows the relationship between how voters perceived Bush's leadership abilities (V035). For the reasons suggested in Exercise 1, you should use the recoded version of V002 that you created for that exercise, so that you examine only the major-party vote (i.e., only the Bush and Kerry voters). After creating this table (Table 9A), create a similar table (9B) using the same question about Kerry's leadership abilities (V042).
Tables 9A and 9B each indicate that perceptions of both Bush's and Kerry's leadership abilities were related to the vote. However, looking at each perception separately does not answer the most interesting question, which is what effect perceptions of differences between the candidates have on the vote. That is, some voters who thought that Bush was a strong leader may also have felt the same about Kerry, in which case they did not see a difference between the candidates on this attribute. Other voters who thought that Bush was a strong leader may have felt that Kerry was not, and this group clearly saw a difference between the candidates on this attribute. To examine the joint influence of V035 and V042 on presidential vote, you should generate a three-variable table. In this case, it does not matter whether V035 is treated as the independent variable and V042 as the control variable or the reverse.