In Exercises 2.20–2.22, identify whether the design is a completely randomized design, randomized complete block design, or Latin square design. If there is a factorial structure for the treatments, specify whether it has a two-factor or three-factor structure. If the measurement units are different from the experimental units, identify both.
2.20. The researchers design an experiment to evaluate the effect of applying fertilizer having varying levels of nitrogen, potassium, and phosphorus on the yields of orange trees. There were three, four, and three different levels of N, P, and K, respectively, yielding 36 distinct combinations. Ten orange groves were randomly selected for the experiment. Each grove was then divided into 36 distinct plots, and the 36 fertilizer combinations were randomly assigned to the plots within each grove. The yield of five randomly selected trees in each plot is recorded to assess the variation within each of the 360 plots.
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An Introduction to Statistical Methods and Data Analysis
- In Exercises 11 –14, test the claim about the difference between two population means u1 and u2 at the level of significance a. Assume the samples are random and independent, and the populations are normally distributed.arrow_forwardSuppose a study was conducted to compare the sleep deprivation rates of Californians and Oregonians. The proportion of California residents who reported insufficient rest or sleep during each of the preceding 30 days is 8.8%, while this proportion is 7% for Oregon residents. These data are based on simple random samples of 1,545 California and 1,460 Oregon adult residents. a) Conduct a hypothesis test to determine if these data provide strong evidence the rate of sleep deprivation is different for the two states. Use California as Group A and Oregon as Group B.Test statistic (Round to 4 decimal places): p-value (round to 4 decimal places): Conclusion at the 5% level of significance: We accept the null hypothesis. We reject the null hypothesis. We fail to reject the null hypothesis. b) It is possible the conclusion of the test in part (a) is incorrect (contradicts with the reality). If this is the case, what type of error was made? Type I Error Type III Error Type II Error A…arrow_forwardA research study recruited 32 adolescent patients with Type 1 diabetes. In random order, each patient received therapy with a bionic pancreas for 5 days and therapy with an insulin pump for 5 days. Is there evidence that, on average, a bionic pancreas helps patients attain a lower plasma glucose level than an insulin pump? Which test is most appropriate for this scenario? 1-sample z-test for proportions B matched-pairs C 1-sample t-test for means D 2-sample test for proportions E 2-sample test for meansarrow_forward
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- Holt Mcdougal Larson Pre-algebra: Student Edition...AlgebraISBN:9780547587776Author:HOLT MCDOUGALPublisher:HOLT MCDOUGAL