A researcher is using an independent-measures design to evaluate the difference between two treatment conditions with n = 8 in each treatment. The first treatment produces M = 63 with a variance of s2 = 18, and the second treatment has M = 58 with s2 = 14.
a. Use a one-tailed test with
b. Predict how the value for the t statistic would be affected if the two sample variances were increased to s2 = 68 and s2 = 60. Compute the new t to confirm your answer.
c. Predict how the value for the t statistic for the original samples would be affected if each sample had n = 32 scores (instead of n = 8). Compute the new t to confirm your answer.
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Essentials of Statistics for the Behavioral Sciences
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