Why a Parameter? Given the results described in Exercise 3, is the mean of 140.0 executives expressed with μ or x ¯ ? Explain why the mean of 140.0 executives is a parameter instead of a statistic.

Answer :

Step 1 :

Given, An Office Team survey of 150 executives found that 93.3% of them said that they would be concerned about gaps in a résumé of a job applicant. Based on these results, such randomly selected groups of 150 executives have a mean of 140.0 executives and a standard deviation of 3.1 executives

Here, the mean is calculated for the population of all groups of 150 executives, not just for one group.Because the mean is calculated for the population, it is a parameter.

Std dev = 3.1

Variance = npq

Where n = 150, p = 0.933 and q = 1 - p = 0.067

Variance = 150(0.933)(0.067)

= 9.3766