A researcher conducts a study of white and black attitudes toward the police in her community.
The percentage of white respondents (N = 300) who say they have a favorable attitude toward the police is 55% with a 95% confidence interval of +/- 5.6%. The percentage of black respondents (N = 250) who say they have a favorable attitude toward the police is 41% +/- 6.1%.
You are asked if there is a real difference between the percentage of whites and blacks who have a positive attitude toward the police in the larger population, or is this sample difference likely to have occurred by random chance or sampling error. How do you respond? Explain your answer.