A researcher uses a repeated-measures design to compare individuals’ performance before treatment with their performance after t
reatment. If all the participants show improved performance of 8 or 9 points after treatment, what should the researcher find _______ a) a sample mean difference near zero.
b) the statistic near zero.
c) the variance of the difference scores is near zero.
d) none of the other options is correct.
c. the variance of the difference scores is near zero
Step-by-step explanation:
If all the participants show improved performance of 8 or 9 points after treatment, what should the researcher find - the variance of the difference scores is near zero.
But this can be true only when the original scores had a low variance.
