In this data lab, we'll use the GSS Cross-Sectional Survey to create a plot evincing the evolution of peoples' attitudes towards interracial marriage and segregation.

Ex-Ante Thought Exercise

 - What do you expect to be the result of this exercise? Do you expect people's attitudes regarding interracial marriage and segregation are correlated? Perfectly correlated? How much of a change has taken place? What do you think is the best way to present the data?

Task Overview
 (1) Preliminaries -- read in the data
 (2) Create summary variables for both topics
     (a) One summary variable describing segregation attitudes
     (b) One summary variable describing interracial marriage attitudes
 (3) Introduce the longitudinal aspect by finding year-by-year summaries of each variable in (2)
 (4) Produce output -- here, a time series plot

Task 1: Read in data

 - data from GSS 1972-2010 Cross-Sectional Cumulative Data 
 - could be downloaded from:
   http://www3.norc.org/GSS+Website/Download/STATA+v8.0+Format/
 - here, we're providing you directly with the .dta file (a Stata binary format)
   - to load this in R, we'll need a new package -- haven
   - run the following command in R
       install.packages("haven")
   - load the package with the following command
       library(haven)
   - The function we want is called read_dta
       gss = read_dta("path/to/gss7210_r2.dta")
     - Replace path/to with the directory on your computer where this data file is located

Task 2: Neighborhood Segregation Variable

 - Create a variable taking the value TRUE if the respondent does not believe that whites "have a right to neighborhood segregation" (and FALSE otherwise)

Task 3: Interracial Marriage Variable

 - Create a variable taking the value TRUE if the respondent does not favor a law against interracial marriage (and FALSE otherwise)

Task 4: Yearly averages

 - For both of the variables form Tasks 2 and 3, create a new variable that captures its yearly average. That is, create a variable that captures the proportion of respondents in each year who do not believe whites have a right to neighborhood segregation (and a second variable about interracial marriage)

Task 5: Plotting

 - Create a graph plotting the proportion of respondents who don't believe that "whites have a right to segegation" and who don't favor a law against interracial marriage, over time. Specifically, the x-axis should be the year and the y-axis should be a percentage.