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 062 5 comma 019 4 comma 877 4 comma 992 4 comma 394 ??? 5 comma 046 4 comma 210 4 comma 154 4 comma 238 4 comma 747 4 comma 230 4 comma 943 Chi-Square critical values. The confidence interval estimate is nothing secless than sigmaless thannothing sec. ?(Round to one decimal place as? needed.)

Answer 1

Following is the output of descriptive statistics :

Descriptive statistics
	X
count	12
mean	4,576.00
sample standard deviation	391.74
sample variance	1,53,459.64
minimum	4062
maximum	5046
range	984

Sample size: n =12

The degree of freedom : df=n-1=11

For 99% confidence interval value critical value of chi sqaure statitics will be

The confidence interval for the population standard deviation is