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SPSS Questions: (12 pts) A researcher would like to investigate whether or not t

ID: 3217425 • Letter: S

Question

SPSS Questions:

(12 pts) A researcher would like to investigate whether or not there is a difference in IQ between Psychology and History majors. She gathers 16 students (8 whose major is Psychology, and 8 whose major is history) and has them all take an IQ test to test this hypothesis using an alpha level of .01. Below are the data:

Psych

History

110

90

120

98

100

100

90

110

124

100

102

120

110

110

123

120

a.(2 pts) What is the appropriate test?

b.(1 pt) State the null hypothesis:

c.(1 pt) State the alternative hypothesis:

d.(2 pts) Find the critical value:

e.(2 pts) Calculate the obtained statistic:

f.(1 pts) Make a decision:

g.(1 pt) What does your decision mean?

h.(2 pts) Use SPSS to perform this same analysis and confirm the same result. Paste your output below:

Psych

History

110

90

120

98

100

100

90

110

124

100

102

120

110

110

123

120

Explanation / Answer

Below are the null and alternate hypothesis for this test:

H0: mu1 = mu2
H1: mu1 not equals to mu2

Here mu1 represents the mean IQ of population with major in Psycology and mu2 for History

The appropriate test to test this hypothesis is, 2 mean difference using t-test. As variances of two population are not same we use unpooled test.

As p-value is greater than the significance level of 0.01 we fail to reject the null hypothesis. This means there is no significant difference in the IQ level of two samples.

Same test is run using EXCEL, below are the results,

Input Given Data Sample 1 Sample 2 Name Psych History mean 109.875 106 Sample size 8 8 Std. dev. 12.12 10.80