Use the following scenario to complete the question 6 through 10. A market resea
ID: 3073420 • Letter: U
Question
Use the following scenario to complete the question 6 through 10. A market researcher for a consumer electronics company wants to stud the media vi of residents of a particular area. A random sample of 40 respondents is selected, and each respondent is instructed to keep a detailed record of time spent engaged viewing content across all screens (traditional TV, DVD/Blue-ray, game console, Internet on a computer, video on a computer, video on a smartphone) in a particular week. The results indicate that the content viewing time per week X-51 hours, and the population standard deviation is estimated as 3 hours. ewing behavicr 6. Construct a 90% confidence interval estimate for the population mean content viewing time per week in this area. (keep 2 digits after the dismal place, e.g. 2.22) 7, Please interpret your result from Question 6.8. Based on the same scenario give, construct a 99% confidence interval estimate for the mean content viewing time per week in this area. (keep 2 digits after the dismal place, e.g. 2.22) 9. If a random sample of 200 is selected, and the content viewing time per week is still X-51 hours. Construct a 90% confidence interval estimate for the population mean content viewing time per week in this area. (keep 2 digits after the dismal place, e.g. 2.22) 10. Compare the answers in Q8 with Q6, we see that when you increase the Confidence Level, the width of confidence interval ; compare the answers in Q9 with Q6, we see that. when you increase the sample size, the width of confidence intervalExplanation / Answer
n = 40 , mean = 51 , s = 3
6)
z value at 90% = 1.645
CI = mean +/- z *(s/sqrt(n))
= 51 +/- 1.645 *(3/sqrt(40))
= (50.22,51.78)
7)
z value at 99% = 2.576
CI = mean +/- z *(s/sqrt(n))
= 51 +/- 2.576 *(3/sqrt(40))
= (49.78,52.22)
9)
n = 200 , mean = 51 , s = 3
z value at 90% = 1.645
CI = mean +/- z *(s/sqrt(n))
= 51 +/- 1.645 *(3/sqrt(200))
= (50.65,51.35)
10)
when you increase the confidence level the width of ci increases
when you increase the sample size , the width of ci decreases