For several combined classes, forty-seven (n=47) students used the how-old.net website.

In one experiment the students took pictures of themselves squinting and another picture with their eyes wide open. This data was to be used to test the null hypothesis that squinting didn't make a difference in the expected age guessed versus the alternative that it would make you look older.

Overall, the ages guessed by the computer averaged 3.64 years older when the students were squinting with a standard deviation of 12.87 years.

1.What is the standard error of the mean in this situation?Show your computations.

2.Find the z-score for the test statistic and then the P-value.

Show your computations for the Z score and explain how you found the p-value. What do you conclude?

(You should arrive at a p-value of about 2 or 3 percent indicating that the null hypothesis that squinting has no affect is a poor explanation of the data.)

3.If we had analyzed the data for just your section of STAT 100 instead of all sections combined, then

A)the P-value probably would be higher

B)the P-value probably would be lower

C)the P-value probably would have stayed the same

4.If we had data for 200 students instead of just 47, then

A)the P-value probably would be higher

B)the P-value probably would be lower

C)the P-value probably would have stayed the same