Research suggests that identical twins have many similarities, such as body weights, even as adults. A sample of ten sets of identical twins were weighed and had their weights recorded in kilograms. The researcher wishes to test whether there is a statistically significant difference in adult weight between first born and second born identical twins. Given the design of the study and the question of interest, which of the following 4 computer outputs is relevent to use?
A. Paired T-Test and Cl
Sample N Mean StDev SE Mean
First-Born 10 77.59 23.38 7.39
Second-Born 10 78.02 17.36 5.49
Difference 10 -0.43 11.83 3.74
95% upper bound for mean difference: 6.43
T-Test of mean difference = 0 (vs < 0): T-value = -0.12 P-value = 0.455
B. Two-Sample T-Test and Cl
Sample N Mean StDev SE Mean
First-Born 10 77.6 23.4 7.4
Second-Born 10 78.0 17.4 5.5
Difference = mu (First=Born) - mu (Second-Born)
Estimate for difference: -0.43
95% upper bound for difference: 15.64
T-Test of difference: 0 (vs <): T-value = -0.05 P-value = 0.482 DF = 16
C. Paired T-Test and Cl
Sample N Mean StDev SE Mean
First-Born 10 77.59 23.38 7.39
Second-Born 10 78.02 17.36 5.49
Difference 10 -0.43 11.83 3.74
95% Ci for mean difference: (-8.89, 8.03)
T-Test of mean difference = 0 (vs not = 0): T-value = -0.12 P-value = 0.911
D. Two-Sample T-Test and Cl
Sample N Mean StDev SE Mean
First-Born 10 77.6 23.4 7.4
Second-Born 10 78.0 17.4 5.5
Difference = mu (First=Born) - mu (Second-Born)
Estimate for difference: -0.43
95% CI for difference: (-19.95, 19.09)
T-Test of difference: 0 (vs not =): T-value = -0.05 P-value = 0.963 DF = 16