Concept explainers
Aphid infestation of fruit trees can be controlled either by spraying with pesticide or by inundation with ladybugs. In a particular area, four different groves of fruit trees arc selected for experimentation. The first three groves arc sprayed with pesticides 1, 2, and 3, respectively, and the fourth is treated with ladybugs, with the following results on yield:
Treatment | ni = Number of Trees |
|
si |
1 | 100 | 10.5 | 1.5 |
2 | 90 | 10.0 | 1.3 |
3 | 100 | 10.1 | 1.8 |
4 | 120 | 10.7 | 1.6 |
Let μi= the true average yield (bushels/tree) after receiving the ith treatment. Then
measures the difference in true average yields between treatment with pesticides and treatment with ladybugs. When n1, n2, n3, and n4 are all large, the estimator
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Chapter 7 Solutions
Probability and Statistics for Engineering and the Sciences
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