TABLE 8-6
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 8-6, this interval requires the use of the t distribution to obtain the confidence coefficient.

Question

Quizplus · Accepted Answer

The confidence interval for a proportion is typically calculated using the normal (Z) distribution, not the t distribution, especially when the sample size is large enough (n=120 in this case).

TABLE 8-6 After an Extensive Advertising Campaign, the Manager of a Company