Question

Using SPSS, the outcome of the data analysis are as follow;

	Paired Differences
					95% Confidence Interval of the difference
		Mean	Std. Deviation	Std. Error Mean	Lower	Upper	T	df	Sig.(2-tailed)
Pair 1	Method A-Method B	5.200	6.125	1.937	0.819	9.581	2.685	9

1-Provide a statement about the finding in this table for paired t-test and it is interpretation?

2-Report the estimate difference for u_a-u_b between the mean scores obtained by children taught by the two methods and its 95% confidence interval?

E. Using the same data, assuming that they are independent sample and not paired. Using SPSS, the outcome of the data analysis as follow.

	Independent Samples Test
		Levene’s Test for equality of variances		t-test for equality of means
									95% Confidence Interval of the difference
		F	Sig.	t	df	Sig.(2-tailed)	Mean Difference	Std. Error Difference	Lower	Upper
Test score	Equal variances assumed	0.153	0.700	1.215	18	.240	5.200	4.280	-3.793	14.193
	Equal variances not assumed			1.215	17.694	.240	5.200	4.280	-3.804	14.204

1-What is the point estimate of the mean difference for test scores, making two possible assumptions for the structure of the data?

2-What is the purpose of levene’s test; and based on the result what does it suggest regarding the variances?

3-Provide a statement about the finding in this table for independent t-test and it is interpretation? [Note: the levene’s test showed equal variance is assumed]

Answer 1

1)We see that the CI(difference)=[0.819,9.581] which means the difference is greater than 0 at 95% interval.

2)Estimate differnce=5.2, CI=[0.819,9.581]

Part E

1)Point estimate=5.2

assumptions are: Equal variance, pooled variance, df=d1+d2-2

2)Levenes test shows us if we can assume the variances are equal. It dggests that the variances are equal.

3)The mean differences in the pooled sample show us that the mean difference is not significantly different from 0. The CI contains 0 in between them.