3. A researcher was interested in the effects of a drug on depression. Subjects were randomly assigned to one of the three groups. Subjects in the control group received a placebo and the subjects in the two treatment groups received either a 0.2 mg or a 0.4 mg dosage of the drug. After several weeks of drug (or placebo) treatment, the researcher measured the subjects' level of depression (a low score indicating greater depression) The following data were obtained. Placebo 0.2 mg 0.4 mg 12 11 12 8 10 9 14 11 11 17 13 13 16 15 7 16 12 Mean of X = 10 14 12 S^2 = 5.6 8.4 4 Using 5% of significance, test the hypothesis that the three groups differ in their effectiveness.

3. A researcher was interested in the effects of a drug on depression. Subjects were randomly assigned to one of the three groups. Subjects in the control group received a placebo and the subjects in the two treatment groups received either a 0.2 mg or a 0.4 mg dosage of the drug. After several weeks of drug (or placebo) treatment, the researcher measured the subjects' level of depression (a low score indicating greater depression) The following data were obtained. Placebo 0.2 mg 0.4 mg 12 11 12 8 10 9 14 11 11 17 13 13 16 15 7 16 12 Mean of X = 10 14 12 S^2 = 5.6 8.4 4 Using 5% of significance, test the hypothesis that the three groups differ in their effectiveness.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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