Question

Gamila was interested in whether her friends' attendance at a party (present/absent) would differ depending on their primary method of travel (car or bus). The results are displayed in the following table. Using the .05 significance level, is attendance related to type of travel?

	Present	Absent
Car	10	3
Bus	20	10

Step 0:  Do you have any reason to be concerned that the assumptions of the test are violated? Why or why not?

Step 1:
Research hypothesis: ?
Null hypothesis: ?

Step 2:
Comparison Distribution Shape
t distribution

Comparison distribution df = ?

Step 3:
Critical value = ?

Answer 1

1. The common assumptions made when doing a t-test include those regarding the scale of measurement, random sampling, normality of data distribution, adequacy of sample size and equality of variance in standard deviation. With the data given to be, we cannot be sure that all the assumptions are met.

2. Research hypothesis: Attendance at a party differs significantly depending on the primary method of travel (car or bus).

Null hypothesis: Attendance at a party does not differ significantly depending on the primary method of travel (car or bus).

3. The df = 41.

4. 20.21 is the critical value.