In a survey conducted in March 2013 by the National Consortium for the Study of Terrorism and Responses to Terrorism, 1515 adults were asked about the effectiveness of the government in preventing terrorism and whether they believe that it could eventually prevent all major terrorist attacks. 37.06% of the 510 adults who consider the government to be very effective believed that it can eventually prevent all major attacks, while this proportion was 28.36% among those who consider the government somewhat, not too, or not at all effective in preventing terrorism. The other people surveyed considered that terrorists will always find a way.

a. Identify the response variable, the explanatory variable, and their categories.

b. Construct a contingency table that shows the counts for the different combinations of categories.

c. Use a contingency table to display the percentages for the categories of the response variables, separately for each category of the explanatory variable.

d. Are the percentages reported in part c conditional? Explain.

e. Sketch a graph that compares the responses for each category of the explanatory variable.

f. Compute the difference and the ratio of proportions. Interpret.

g. Give an example of how the results would show that there is no evidence of association between these variables.