Recently, a group of students was interested in the different factors that influence people to pet walked dogs. They compiled a list of all possible time slots between classes on school days from March 1 - April 16, 2004 (not including Spring Break or Good Friday) at ten locations on TAMU campus. First, they randomly selected 20 time slots to walk a small dog, and then they used a completely different set of random numbers to select 20 times slots to walk a big dog. Timeslots that occurred on rainy days were thrown out of the sample (3 walks for the small dog were cancelled). For each walk, the researchers recorded the number of people that stopped to pet the dog. The sample mean and sample standard deviation for number of people stopping to a big dog are 2.75 and 3.00657. For a small dog, those values are 7.52941 and 5.72405. The data from this study is used to test the claim "the average number of people who pet large dogs is different from the number who pet small dogs." Assume the test is done at the ? = 0.05 significance level.

(a) What is the response variable and what type of variable is it?

Size of dog, categorical

Size of dog, numerical

Number of people stopping to pet dog, categorical

Number of people stopping to pet dog, numerical

(b) Are the conditions satisfied for conducting an Independent Samples T Test on this data set?

No, because although the data was gathered randomly, there are less than 30 dogs in each group.

Yes, because the data was gathered randomly and there are more than 15 dogs in each group.

Yes, because the data was gathered randomly and there are more than 30 dogs total.

Yes, because the data was gathered randomly and the plots for each group do not reveal any strong skewness or extreme outliers.

(c) What is the p-value?

0.995

0.001

0.010

0.005

(Use 4 decimal places)