Question

8) Two high schools have a similar number of students and parking lots of similar size. The safety officers at both schools want to investigate whether there is an average difference in the number of cars parked per day in the student parking lots for the school year. A random sample of 15 school days will be selected. For each selected day, the number of cars parked in the student parking lots will be counted at both schools and the difference will be recorded. Assuming all conditions for inference are met, which of the following is the appropriate test for the investigation? A two-sample 2-test for a difference between proportions ® A two-sample t-test for a difference between means © A matched-pairs t-test for a mean difference O A chi-square test of homogeneity e A chi-square test of independence

Answer 1

Here two diffrent investigators are taking data for two schools for investigating number of parked cars independebtly. There is no such case that two different investigators are investigating the data of parked cars in a particular school. So we can not see any sign of dependency in survey of data. Two diffrent investigators, two different schools, two different parking lots. So when they are collecting data its completely independent from each other . And here sample size is also very small according to large sample theory . N=15(<30). So we can not perform Z test for this case. So to test the difference of number of parked cars for both school we would like to perform A two sample t - test for a difference between means.

please study the notion about independent sample t test , matched paired sample t test . And for further knowledge study z- test.