Question

You are interested in investigating whether the type of computer a person primarily uses and the type of car they drive are dependent. The table below shows the results of a survey.

Frequencies of Computer and Car Types

	Sedan	SUV	Truck
Tablet	72	98	50
Notebook	87	96	30
Desktop	106	103	22

What can be concluded at the αα = 0.10 significance level?

1. What is the correct statistical test to use?
   • Paired t-test
   • Homogeneity
   • Goodness-of-Fit
   • Independence
2. What are the null and alternative hypotheses?
   H0:H0:
   • The distribution of computer types is not the same for each car type.
   • Computer type and car type are independent.
   • Computer type and car type are dependent.
   • The distribution of computer types is the same for each car type.
   
   
   
   H1:H1:
   • The distribution of computer types is the same for each car type.
   • The distribution of computer types is not the same for each car type.
   • Computer type and car type are independent.
   • Computer type and car type are dependent.
3. The test-statistic for this data = (Please show your answer to three decimal places.)
   
4. The p-value for this sample = (Please show your answer to four decimal places.)
   
5. The p-value is Select an answergreater thanless than (or equal to) αα

Answer 1

a)Independence (since we are checking if variables are independent)

b) Ho:Computer type and car type are independent.

H1: Computer type and car type are dependent.

c)

Applying chi square test of independence:

Expected	Ei=row total*column total/grand total	Sedan	SUV	Trruck	Total
	Tablet	87.801	98.404	33.795	220
	Notebook	85.008	95.273	32.720	213
	Desktop	92.191	103.324	35.485	231
	total	265	297	102	664
chi square    χ2	=(Oi-Ei)2/Ei	Sedan	SUV	Trruck	Total
	Tablet	2.8437	0.0017	7.7702	10.6156
	Notebook	0.0467	0.0056	0.2261	0.2783
	Desktop	2.0683	0.0010	5.1245	7.1939
	total	4.9587	0.0082	13.1208	18.0878
test statistic X2 =		18.088

d) p value =0.0012

e)  he p-value is < alpha