3. During each of four experiments on the use of carbon tetrachloride as a worm killer, ten rats were infested with larvae (Armitage 1983). Eight days later, five rats were treated with carbon tetrachloride; the other five were kept as controls. After two more days, all the rats were killed and the number of worms were killed. The table below gives the counts of worms for the four control groups. Significant differences, although not expected, might be attributable to changes in experimental conditions. A finding of significant differences could result in more carefully controlled experimentation and thus greater precision in later work. Use both graphical techniques (e.g. boxplots) and the F test to test whether there are significant differences among the four groups. Group I Group II Group II Group IV 279 378 172 381 338 275 335 346 334 412 335 340 198 265 282 471 303 286 250 318

3. During each of four experiments on the use of carbon tetrachloride as a worm killer, ten rats were infested with larvae (Armitage 1983). Eight days later, five rats were treated with carbon tetrachloride; the other five were kept as controls. After two more days, all the rats were killed and the number of worms were killed. The table below gives the counts of worms for the four control groups. Significant differences, although not expected, might be attributable to changes in experimental conditions. A finding of significant differences could result in more carefully controlled experimentation and thus greater precision in later work. Use both graphical techniques (e.g. boxplots) and the F test to test whether there are significant differences among the four groups. Group I Group II Group II Group IV 279 378 172 381 338 275 335 346 334 412 335 340 198 265 282 471 303 286 250 318

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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