In a study of differences n manual ability between dominant

In a study of differences n manual ability between dominant and non - dominant hands, the researcher produced the following anaIysis of differences in time required (in seconds) to turn a research designed knob by 28 right handed participants with only their right (dominant) hands and only their left (non - dominant) hands. Here is the StatCrunch output. Please use the t - Tables only. What can you conclude from the above analysis? The data show clear evidence that there is no difference in manual skills between dominant and non - dominant hands in right handed people. NO conclusion can be made. The data show no evidence that dominant hands are more manually skilled in right handed people. The data show clear evidence that dominant hands are more manually skilled in right handed people.

Solution

The test statistic is

t=(sample diff. -8)/std. error

=(15.357-8)/3.673

=2.002995

The p-value= P(t with df=27 >2.002995) =0.0277 (from standard normal table)

The data are statistically significant at a=0.1 and a=0.05