MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
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To investigate the effect of four treatments on change in body fat mass each of 74 male subjects who were over age 65 was assigned at random to one of the following four treatments: (1) placebo "growth hormone" and placebo "steroid" (denoted by P + P), (2) placebo "growth hormone" and the steroid testosterone (denoted by P + S), (3) growth hormone and placebo "steroid" (denoted by G + P), and (4) growth hormone and the steroid testosterone (denoted by G + S). The accompanying table lists data on change in body fat mass over the 26-week period following the treatment. Carry out an F test to see whether true mean change in body fat mass differs for the four treatments if
N = 74,
grand total
T = −157.7,
and
=
= −2.1311.
(Use a significance level of 0.05.)| T |
| N |
Change in Body Fat Mass (kg)
| Treatment | P + P | P + S | G + P | G + S |
|---|---|---|---|---|
| 0.4 | −3.6 | −3.7 | −5.1 | |
| 0.5 | −0.9 | −3.1 | −5.1 | |
| −1.6 | 0.1 | −5.0 | −2.9 | |
| −0.4 | −2.2 | −5.1 | −2.7 | |
| −2.0 | 1.6 | −2.3 | −6.3 | |
| 1.2 | −1.3 | −3.6 | −7.1 | |
| 0.9 | 1.1 | −4.5 | −4.6 | |
| 1.4 | −2.6 | −0.9 | −4.3 | |
| −1.1 | −3.4 | −1.9 | −5.1 | |
| −0.3 | 0.3 | −3.9 | −6.3 | |
| 1.6 | 0.5 | −1.8 | −4.1 | |
| 1.3 | −0.8 | −2.9 | −3.8 | |
| 0.7 | 0.0 | −1.7 | −3.4 | |
| 0.5 | −3.0 | −2.8 | −5.6 | |
| −1.2 | 0.2 | −2.8 | −4.6 | |
| −0.1 | −0.4 | −2.8 | −4.2 | |
| 0.8 | −0.7 | −3.8 | −3.9 | |
| −0.8 | −4.3 | |||
| −0.8 | −4.8 | |||
| −2.1 | ||||
| −0.7 | ||||
| n | 17 | 21 | 17 | 19 |
| x | 0.1529 | −0.9286 | −3.0941 | −4.6421 |
| s | 1.0989 | 1.4343 | 1.1776 | 1.1413 |
| s2 | 1.2076 | 2.0571 | 1.3868 | 1.3026 |
Calculate the test statistic and find the P-value. (Round your answer to four decimal places.)
F =
P-value =
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