Question

TWO MEANS – INDEPENDENT SAMPLES

Choose a variable from the advising.sav data set to compare group means. While the choice of which variable to test is up to you, you must remember that it must be a metric variable. The grouping variable, which is used to define the two groups to be compared, must be categorical.   You can look in the “Measure” column of the “Variable View” in the data file for help in determining which is which. The managerial question is whether or not there is a significant difference between the groups for the metric variable you have chosen.

Once you have the results, report your findings using the five step hypothesis testing procedure outlined in class. (See below.)   For Step 4, simply cut and paste the SPSS output into the report. This can be done by clicking on the desired portion of the output which will then be highlighted, and then right clicking on the highlighted portion and copying it to your flash drive. (Note that you may want to drop the results into a word document immediately since if you do not have SPSS on your personal laptop, you will not be able to open any SPSS output.) Then state the answer to the managerial question that was initially posed. For example, is there a significant difference between the two groups defined by the grouping variable (which you must identify in your report) for the metric variable tested? Also, interpret the confidence interval provided for the test. Does it indicate a significant difference or not?   

PAIRED SAMPLE T-TEST

Choose a pair of metric variables and run a paired sample t-test on the pair. Again, these must be metric variables. The managerial question will be “Is there a significant difference between the two variables?” for the pair. Report your findings using the same procedure described above, including an interpretation of the confidence interval.

REPORT(SAMPLE)

Your report will consist of two hypotheses tests, (one for the independent sample test and one for the paired sample test). It will look something like this (for the independent sample test):

1: H₀: μ₁= μ₂

H_a: μ₁ ≠ μ₂

2: Two group independent sample t-test (note that SPSS does everything as a t-test regardless of sample size).

3: α=.05 → t_crit = ±whatever the appropriate value is

4

Group Statistics
	status	N	Mean	Std. Deviation	Std. Error Mean
dotest	0	185	1494.071	2249.4948	165.3861
	1	50	803.280	1080.0304	152.7394

Independent Samples Test
		Levene's Test for Equality of Variances		t-test for Equality of Means
		F	Sig.	t	df	Sig. (2-tailed)	Mean Difference	Std. Error Difference	95% Confidence Interval of the Difference
									Lower	Upper
dotest	Equal variances assumed	13.465	.000	2.104	233	.036	690.7914	328.2585	44.0572	1337.5255
	Equal variances not assumed			3.068	169.287	.003	690.7914	225.1264	246.3747	1135.2080

5: Make a decision regarding the null hypothesis and interpret the confidence interval.

6: Answer the managerial question.

RESULT

INDEPENDENT

Group Statistics
	Gender	N	Mean	Std. Deviation	Std. Error Mean
OverallSatisfaction	Female	131	4.97	1.771	.155
	Male	145	4.99	1.488	.124

Independent Samples Test
		Levene's Test for Equality of Variances		t-test for Equality of Means
		F	Sig.	t	df	Sig. (2-tailed)	Mean Difference	Std. Error Difference	95% Confidence Interval of the Difference
									Lower	Upper
OverallSatisfaction	Equal variances assumed	5.905	.016	-.120	274	.904	-.024	.196	-.410	.363
	Equal variances not assumed			-.119	255.054	.905	-.024	.198	-.414	.366

PAIRED

Paired Samples Statistics
		Mean	N	Std. Deviation	Std. Error Mean
Pair 1	DesiredConvenience	6.20	273	1.175	.071
	ActualConvenience	4.55	273	1.636	.099

Paired Samples Correlations
		N	Correlation	Sig.
Pair 1	DesiredConvenience & ActualConvenience	273	.213	.000

Paired Samples Test
		Paired Differences					t	df	Sig. (2-tailed)
		Mean	Std. Deviation	Std. Error Mean	95% Confidence Interval of the Difference
					Lower	Upper
Pair 1	DesiredConvenience - ActualConvenience	1.648	1.799	.109	1.434	1.863	15.140	272	.000

PLEASE ANSWER INDEPENDENT AND PAIRED REPORT

Answer 1

for the variable dotest ,

the independent sample t-test is showed that p-value (equal variance=0.036 and un-equal variance=0.003) is less than typical level of significance=0.05, so we reject the null hypothesis

for the variable OverallSatisfaction

the independent sample t-test is showed that p-value (equal variance=0.904 and un-equal variance=0.905) is more than typical level of significance=0.05, so we fail to reject the null hypothesis. but using paired t-test , the p-value=0.000 is less than typical level of significance=0.05, so we reject the null hypothesis.