In: Statistics and Probability
Plot | Fertilizer A | Fertilizer B | Fertilizer C |
1 | 563 | 588 | 575 |
2 | 593 | 624 | 593 |
3 | 542 | 576 | 564 |
4 | 649 | 672 | 653 |
5 | 565 | 583 | 556 |
6 | 587 | 612 | 590 |
7 | 595 | 617 | 607 |
8 | 429 | 446 | 423 |
9 | 500 | 515 | 483 |
10 | 610 | 641 | 626 |
11 | 524 | 547 | 523 |
12 | 559 | 586 | 568 |
13 | 546 | 582 | 551 |
14 | 503 | 530 | 502 |
15 | 550 | 573 | 567 |
16 | 492 | 518 | 495 |
17 | 497 | 529 | 513 |
18 | 619 | 643 | 626 |
19 | 473 | 497 | 479 |
20 | 533 | 556 | 540 |
g) Assuming population mean of crop yield is 570 bushels for all fertilizers with standard deviation of 40 bushels for all. Formulate a test hypothesis that crop yield by applying fertilizer C differs from the population crop yield for all fertilizers. Conduct the hypothesis test, conclude your analysis and explain your answer. Use both critical value and p-value approach with alpha=0.05
h) Calculate a 90% confidence interval estimate of the difference between the population mean yield of fertilizers B and A. Can we conclude at 0.05 level of significance, that the crop yield using fertilizer B is greater than the crop yield using fertilizer A? (hint: you can use the template in chapter 10 to calculate degrees of freedom and the standard error)
i) If we assume that observations are now plots of lands, can the scientist infer that there are differences between the three types of fertilizers?
* Only need help with question i)