Question

How Different?

For this discussion, you will compare a group of acquaintances to the population in regards to social media use. Consider the following: Analyzes of national data have suggested that the adult population uses social media an average of 3 hours per day, with a standard deviation of 1 hour. Develop a main response in which you address the following:

• Ask a group of friends (or other acquaintances) how many hours they spent on social media the previous day.
• Calculate the mean for this group (this is your sample mean).
• Use this value, along with the population mean and standard deviation provided above, to conduct a one-sample z-test.
• Share your z-test and the results on the discussion board.
• Explain whether or not the difference between your sample and the population is statistically significant.
• Discuss some reasons for this significant difference or lack thereof.

Please post a response of your own first, and then reply to at least two classmates.

Answer 1

For doing the study, I had asked 20 of my friends in my locality of the dusration in hours(rounded to the nearest hour) that he/she spent on social media like tv, internet, mails, facebook,...

The follwing data was recorded:

3 1 2 0 3 0 3 5 3 3 2 4 3 3 0 3 2 3 6 2

For this particular dataset, the mean duartion of time spent on media is 2.55 hrs.

It is given that the population mean is hours with the standard deviation .  

One-sample z-test:

Objective: To find out whether the avearge duration spent on media is significant from teh population average of 3 hours or not.

Null Hypothesis H0: The sample mean =population mean ie

Alternative Hypothesis: H1: The sample mean >population mean ie . In this case, I am testing the hypothesis that my sample of the population spends more time than the population on media.

Test Statistics;

Decision: Null hypothesis will be rejected if the calculated value or the p-value is <0.05.

For this particular example, the p-value calculated (using excel) is 0.9779. Since this p-value is more than 0.05, the null hypothesis is not rejected that means, the sample's duration on media can be regarded as the same that of the population.

My sample lacks significance because most of the duration are lesser than the population mean of 3 hours and in 3 individuals they are 0. This may be bacause of this fact.