TABLE 8-7
After an extensive advertising campaign, the manager of a company wants to estimate the proportion of potential customers that recognize a new product. She samples 120 potential consumers and finds that 54 recognize this product. She uses this sample information to obtain a 95% confidence interval that goes from 0.36 to 0.54.
-Referring to Table 8-7, this interval requires the assumption that the distribution of the number of people recognizing the product has a normal distribution.

Question

TABLE 8-7
 After an extensive advertising campaign, the manager of a company wants to estimate the proportion of potential customers that recognize a new product. She samples 120 potential consumers and finds that 54 recognize this product. She uses this sample information to obtain a 95% confidence interval that goes from 0.36 to 0.54.
-Referring to Table 8-7, this interval requires the assumption that the distribution of the number of people recognizing the product has a normal distribution.

Quizplus · Accepted Answer

The confidence interval for a proportion is based on the normal approximation to the binomial distribution, not the assumption that the number of people recognizing the product follows a normal distribution.

TABLE 8-7 After an Extensive Advertising Campaign, the Manager of a of a Company