political inquiry (statistics)
political inquiry (statistics)
Click here to order this paper
Part A. Crosstabs and Summary Tables
1. A survey organization recently conducted a random sample of 1000 individuals from the
population of American adults. The survey assessed the relationship between religiosity and
partisanship. It asked the individuals whether religion is an important part of your life,” and
asked them if they think of themselves as Democrats, Republicans, or Independents. The
results were as follows:
a. Calculate appropriate percentages for the table, justify your choice of row, column, or total
percentages, and comment on the relationship.
b. Construct a 95% confidence interval for the proportion of American adults who claim
that religion is important to them. Show your work and tell us what your results suggest
about the overall population of all American adults.
c. Suppose that you only had a sample of 100 subjects but the same proportions. What
would the confidence interval be? Now, suppose you had a sample of 10,000 subjects. What
would the confidence interval be? Since polling firms charge based on the number of
respondents, which size sample (n=100, n=1000, n=10,000) seems like the best deal?
Part B. Correlation and Regression
Consider the following dataset which contains Years of Education (IV) and Starting
Monthly Income in Thousands (DV).
1. Make a scatterplot (by hand) of the following dataset. Do your best – it doesn’t have
to be perfect. Comment on the plot.
2. Calculate the correlation coefficient, R^2, regression slope and intercept (by hand,
and show your work), and interpret them for the following dataset.
Partisanship Religion Not Important Religion Important Total
Democrat 130 220 350
Independent 85 255 340
Republican 100 210 310
Total 315 685 1000
Part C. Initial Test for Your Data Project (USE STATA!!!)
You are going to begin to explore the relationships between one of the independent
variables in your hypothesis and your dependent variable. We’ll wait until the final homework
to ask you to conduct tests of statistical significance.
1. Restate your hypothesis from the first homework (or a new hypothesis if you have
changed direction). Restate the types of the variables in your hypotheses.
2. With only one of your independent variables, use Stata to produce a graph and table
of the bivariate relationship between this independent variable and your dependent
variable. Do they appear to be related? Describe the pattern you see. (Include a
print-out of the Stata graph and/or output AND code or log).
An important part of this assignment is figuring out which tool you should use –
YOU must decide what kind of table and what kind of graph to make. The answer
depends on the type of variable you chose for your independent variable and for your
dependent variable. Ask for help here if you need it.
Education in
Years
Starting Monthly
Income in Thousands
12 1
12 2
14 3
16 4
16 5
IV DV Nominal Ordinal Interval Ratio
Nominal Crosstab and Bar
plot
Crosstab and Bar
plot
Summary Table
and Summary
bar plot
Summary Table
and Summary
bar plot
Ordinal Crosstab and Bar
plot
Crosstab and Bar
plot
Summary Table
and Summary
bar plot
Summary Table
and Summary
bar plot
Interval Recode IV into
groups, then
crosstab or bar
plot
Recode IV into
groups, then
crosstab or bar
plot
Scatterplot and
Regression
Table
Scatterplot and
Regression
Table
Ratio Recode IV into
groups, then
crosstab or bar
plot
Recode IV into
groups, then
crosstab or bar
plot
Scatterplot and
Regression
Table
Scatterplot and
Regression
Table
