**Categorical Lab #5
Assignment**

Please
use the "turnout" dataset within the Zelig
package, which details a random subset of 2000 individuals (out of 15,837
surveyed) during the 1992 presidential election. There are 5 variables in these
data: race (whether the participant was "white"
or nonwhite ["others"]), age (how old the participant
was at the time), educate (the participant's
years of education), income (a categorical
measure of the participant's level of income), and vote
(whether the participant voted or not [1 = voted, 0 = did not vote]).

To
access this dataset, first call the Zelig package
[i.e., library(Zelig)], then use data(turnout)
to "attach" the dataset to R. You may then use the turnout dataset
in R.

1. Run a logistic regression, with vote as the dependent variable and educate as
the independent variable. Please report the beta estimate of the effect of educate on vote, and
provide a meaningful interpretation of this estimate.

2. Provide a 95% profile likelihood ratio
confidence interval and a 95% Wald confidence interval of the beta estimate in
Question 1. Translate the intervals into odds and provide a meaningful
interpretation of each confidence interval. According to each confidence
interval, is the estimate significant?

3. Create a probability plot for the logistic
regression in Question 1. Provide this plot. Calculate the probability for the
following questions: What is the probability of voting at a high school
education (12 years)? At a college education (16 years)? At the mean level of
education?

4. What is the median effective
level of education for this model? In other words, what is the value of education
at which the probability of voting is 50%? What significance does this point
have for the rate of change of the probability?