In: Math
A researcher conducts a study of white and black attitudes toward the police in her community.
The percentage of a random sample of white respondents (N = 200) who say they have a favorable attitude toward the police is 53%. The percentage of a random sample of black respondents (N = 200) who say they have a favorable attitude toward the police is 45%.
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.
Construct a 95% confidence interval for the proportion of Blacks in the population who have a favorable attitude toward the police
For White Respondents:
For Black Respondents:
Null and Alternative Hypothesis
Test statistic:
At = 0.05, the critical value = 1.96
As z= 1.605 < =1.96. so we do not reject H0.
Thus there is not enough evidence to claim that there is a real difference between the percentage of whites and blacks who have a positive attitude toward the police in the larger population.
95% confidence interval for the proportion of Blacks
At = 0.05, the critical value = 1.96