Question

Twelve different video games showing substance use were observed and the duration of times of game play​ (in seconds) are listed below. The design of the study justifies the assumption that the sample can be treated as a simple random sample. Use the sample data to construct a 99​% confidence interval estimate of sigma​, the standard deviation of the duration times of game play. Assume that this sample was obtained from a population with a normal distribution. 4 comma 833 5 comma 033 4 comma 292 4 comma 093 4 comma 506    4 comma 621 4 comma 392 4 comma 646 3 comma 864 4 comma 437 3 comma 835 4 comma 338

Answer 1

From the given sample data :

The sample size is , n=12

The sample standard deviation is ,

The critical values are ,

; The Excel function is , =CHIINV(0.005,11)

; The Excel function is , =CHIINV(0.995,11)

Therefore , the 99​% confidence interval estimate of sigma​, the standard deviation of the duration times of game play is ,