1. (R Companion Ch 4, Exercise 2, 20 points): Dataset: nes. Variables: gay_marry, libcon3, wt.) Should gay couples be legally permitted to marry? This controversial issue has gained center stage in political debate. One can imagine several characteristics that divide people on this issue. For example, one could hypothesize that self-described liberals are more likely to favor gay marriage than are self-described moderates, who in turn are more likely to favor gay marriage than are self-described conservatives.

Dataset nes contains gay_marry, a two-level factor that gauges approval of same-sex marriage: "No" or "Yes". Nes also has libcon3, a three-category factor that measures respondents' ideological leanings: "Lib", "Mod", or "Cons".

a. Use xtp to test the following hypothesis about the relationship between libcon3 (independent variable) and gay_marry (dependent variable): In a comparison of individuals, liberals will be more likely to favor gay marriage than will moderates, who in turn will be more likely to support gay marriage than will conservatives. In the xtp syntax, add labels to the mosaic plot: a y-axis label ("Opinion on Gay Marriage"), an x-axis label ("Ideology"), and a main title ("Gay Marriage Opinions, by Ideology"). Print the mosaic plot.

b. Fill in the numbers of cases (N) and column percentages (%) next to the question marks (?) in the table that follows. (Two of the values have been entered for you.)

Opinion on Gay Marriage Lib Mod Cons Total No N 611 ? ? ? % 32.6 ? ? Yes N ? ? ? ? Total N ? ? ? ? Ratings of Tea Party, by Perceived Government Threat and Political Knowledge Political Knowledge (polknow3) Perceived Threat of Government (dis_threat3) Low know Mid know High know None 7 Mod Extrm