|IQ, Income, and the 2004 US Presidential Election
The data were extracted from the page at http://www.sq.4mg.com/stateIQ-income.htm by Jim Clark, who kindly posted them on the Teaching in the Psychological Sciences listserv. The subjects are states in the US. In the plain text data file each record represents one state. The first variable is the average IQ in the state (estimated from SAT and ACT means), the second is the name of the state, the third is the average income in the state (in thousands of dollars), the fourth is a dummy variable representing how the state voted (0 = for Kerry, 1 = for Bush), and the fifth is simply the name of the candidate for whom the state voted.
These data can be used to explore the relationships among income, IQ, and voting. To read them into SAS and get a quick look at the correlations among the variables, use the following statements (change the infile statement to point at the location of the data file on your computer):
options pageno=min nodate formdlim='-';
proc format; value bk 0='Kerry' 1='Bush'; run;
title 'Income, IQ, and Presidential Voting'; run;
data Voting; infile 'D:/StatData/Bush-Kerry2004.txt';
input IQ state $ income vote candidate $; format vote bk. ;
proc corr; var vote iq income; run;
Since we are covering independent samples t now, please use t to test the null hypotheses that states that went for Bush do not differ from states that went for Kerry on IQ and on income. Do compute g, but don’t bother computing a confidence interval for d.
Thought Question: If the 50 states and the D.C. are the sample, what is the population?
Download the Data:
See the correlation matrix below. Remember that high scores on vote represent voting for Bush and low scores voting for Kerry.