The average duration of sustained attention for adults is = 20 minutes. There is speculation that social media platforms such as Vine or TikTok affect our attention span. The researcher recruits a sample of n = 15 individuals and has them watch several 15-second clips for 20 minutes every day. After a month, the researcher measures the sample's attention span and finds the average duration of attention is M = 18 minutes, s = 4 minutes. Is there a significant effect of consuming short-term media on attention span?

1. Based on the question above, should a one-tailed or two-tailed test be used?

2. State your hypotheses ( = .05)

3. Find the critical region

4. Compute the test statistic(s_M= 1.03)

5. Make a decision

6. Interpret the results

A manufacturer of smartphones knows that the average lifetime for a particular model of phone is 24 months. Someone in the research and development division of the company claims to have developed a longer lasting product. This new product was given to a sample of n = 25 individuals and lasted on average for M = 26 months, s = 5.5 months. Is the designer's claim of a better phone supported by the trial results?

1. Based on the question above, should a one-tailed or two-tailed test be used?

2. State your hypotheses ( = .05)

3. Find the critical region

4. Compute the test statistic(s_M= 1.1)

5. Make a decision

6. Interpret the results