Explanation from: https://www.youtube.com/watch?v=U4YlQauDY_c
Explanation from: https://www.youtube.com/watch?v=yFpw1pVZP00
| Case Study 1 (20 marks) | ||||||||
| A new fertilizer has been developed to increase the yield on crops, and the makers of the fertilizer want to better | ||||||||
| understand which of the three formulations (blends) of this fertilizer are most effective for wheat, corn, soybeans | ||||||||
| and rice (crops). They test each of the three blends on one sample of each of the four types of crops. The crop yields | ||||||||
| for the 12 combinations are as shown in Table 1. | ||||||||
| Wheat | Corn | Soy | Rice | |||||
| Blend X | 123 | 138 | 110 | 151 | ||||
| Blend Y | 145 | 165 | 140 | 167 | ||||
| Blend Z | 156 | 176 | 185 | 175 | ||||
| Case Study 2 (20 marks) | ||||||||
| A manufacturer wishes to determine the effectiveness of four types of machines (A, B, C, and D) in the production | ||||||||
| of bolts. To accomplish this, the numbers of defective bolts produced by each machine in the days of a given week | ||||||||
| are obtained for each of two shifts; the results are shown in the table below. Perform an analysis of variance to | ||||||||
| determine at the 0.05 significance level whether this is a difference (a) between the machines and (b) between the shifts. | ||||||||
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