Vermont maple sugar producers sponsored a testing program to determine the benefit of a potential new fertilizer regimen. A random sample of 27 maple trees in Vermont were chosen and treated with one of three levels of fertilizer suggested by the chemical producer. In this experimental setup, nine trees (three in each of three climatic zones) were treated with each fertilizer level and the amount of sap produced (in mL) by the trees in the subsequent season was measured. The results are presented in the following table. Southern Zone Central Zone Northern Zone 76.2 80.4 74.2 79.4 87.9 86.9 84.5 85.2 80.1 Low fertilizer Medium 87.0 95.1 93.0 98.2 94.7 96.2 88.4 90.4 922 fertilizer High 84.2 87.5 83.1 90.3 89.9 93.2 81.4 84.7 82.2 fertilizer Estimate the main effects of fertilizer levels and climatic zone, and their interactions. b. Construct an ANOVA table. You may give ranges for the P-values. Test the hypothesis that there is no interaction between fertilizer levels and climatic zone. d. Test the hypothesis that there is no difference in sap production for the three fertilizer levels.

In a study conducted at Virginia Tech, the plasma ascorbic acid levels of pregnant women were compared for smokers versus nonsmokers. Thirty women in the last three months of pregnancy, free of major health disorders and ranging in age from 15 to 32 years, were selected for the study. Prior to the collection of 20 ml of blood, the participants were told to avoid breakfast, forgo their vitamin supplements, and avoid foods high in ascorbic acid content. From the blood samples, the accompanying plasma ascorbic acid values were determined, in milligrams per 100 milliliters. Is there sufficient evidence to conclude that there is a difference between plasma ascorbic acid levels of smokers and nonsmokers? Assume that the two sets of data came from normal populations with unequal variances. Use a P-value. Click the icon to view the plasma ascorbic acid values. Let sample 1 be the nonsmokers and let sample 2 be the smokers. State the null and alternative hypotheses. Hoi Hi-H2 = 0 (Type integers…

A screening test for a newly discovered disease is being evaluated. To determine the effectiveness of the new test, it was administered to 880 workers, and 120 of the individuals diagnosed with the disease tested positive. A negative test finding occurred in 50 people who had the disease. A total of 40 persons not diseased tested positive for it. Construct a 2 x 2 table similar to Table 12-1 and calculate the following: 1. Prevalence of the disease 2. Sensitivity 3. Specificity 4. Predictive value positive 5. Predictive value negative 6. Likelihood ratio positive 7. Likelihood ratio negative 8. Overall accuracy.

The percentage crude protein content of hay was determined based on 10 bale samples collected from each of four locations (plots as treatments) on a large ranch as follows: Plot A 12.8 13.4 11.2 11.6 9.4 10.3 14.1 11.9 10.5 10.4 b. Plot B 8.1 10.3 4.2 7.8 5.6 8.1 12.7 6.8 6.9 6.4 Plot C 9.8 10.6 9.1 4.3 11.2 11.6 8.3 8.9 9.2 6.4 Plot D 16.4 8.2 15.1 10.4 7.8 9.2 12.6 11.0 8.0 9.8 Set up and complete an ANOVA table for a one-way analysis. Show all work.

oli.cmu.edu/course/a2/rest/assessement/deliver?attempt=1&context=7e118d530a0001dc243d5eafc726f6eb Countdown: Days:-0 Time:-12:02:41 10 points Researchers created a new fertilizer. They conducted an experiment to compare the new fertilizer to the old fertilizer. They divided tomato plants into two groups. They applied the new fertilizer to one group and the old fertilizer to another group. The variable is the number of tomatoes per plant on a randomly selected day. 0 0 Old Fertilizer N=65 2 4 New Fertilizer N=58 4 6 6 20 600 8 8 10 10 12 14 16 12 14 Number of tomatoes per plant 18 16 18 20 20 Select one answer. Which one of the following statements is valid? A. O The new formula of fertilizer works better. Plants with the new fertilizer had more tomatoes. B. O The old formula of fertilizer was better because the plant with the most tomatoes was treated with the old fertilizer. The average number of tomatoes per plant with the old fertilizer is higher than the average amount of tomatoes…

A researcher would like to examine how the chemical tryptophan, contained in foods such as turkey, can affect mental alertness.  A sample of n = 9 college students is obtained and each student’s performance on a familiar video game is measured before and after eating a traditional Thanksgiving dinner including roast turkey.  The average score dropped by M = 14 points after the meal with SS = 1152 for the difference scores. A. Is there is significant difference in performance before eating versus after eating?  Use a                two-tailed test with α = .05.             SMD = ___________________________             tcritical =     ________________________             tcalculated =    ________________________                  Decision = _______________________             B. Compute r2 to measure the size of the effect.             r2  = _____________________________   C. Write a sentence demonstrating how the outcome of the test and the measure of effect                size would…

A deficiency of the trace element selenium in the diet can negatively impact growth, immunity, muscle and neuromuscular function, and fertility. The introduction of selenium supplements to dairy cows is justified when pastures have low selenium levels. Authors of a research paper supplied the following data on milk selenium concentration (mg/L) for a sample of cows given a selenium supplement (the treatment group) and a control sample given no supplement, both initially and after a 9-day period. Initial Measurement Treatment Control 11.4 9.1 9.6 8.7 10.1 9.7 8.5 10.8 10.2 10.9 10.6 10.6 11.9 10.1 9.9 12.3 10.7 8.8 10.2 10.4 10.3 10.9 11.4 10.4 9.3 11.6 10.6 10.9 10.9 8.3   After 9 Days Treatment Control 138.3 9.2 104 8.9 96.4 8.9 89 10.1 88 9.6 103.8 8.6 147.3 10.4 97.1 12.4 172.6 9.2 146.3 9.5 99 8.4 122.3 8.8 103 12.5 117.8 9.1 121.5 93   (a) Use the given data for the treatment group to determine if…

Six samples of each of four types of cereal grain grown in a certain region were analyzed to determine thiamin content, resulting in the following data (µg/g). Wheat 5.2 4.4 6.1 6.2 6.6 5.8 Barley 6.5 7.9 6.0 7.6 6.0 5.7 Maize 5.8 4.6 6.4 4.9 6.0 5.2 Oats 8.4 6.2 7.8 7.1 5.4 7.2 USE SALT Does this data suggest that at least two of the grains differ with respect to true average thiamin content? Use a level α = 0.05 test. State the appropriate hypotheses. | H₂: M₁ = H₂ = H3 = H4 H₂: all four μ's are unequal • Ho: M₁ = H₂ = H3 = H4 H₂: at least two μ's are unequal ⒸH₂² H₁ H₂ H3 H4 # H: all four μ's are equal O Ho: M₁ #M₂ #H3 H4 H₂: at least two μ's are equal Compute the test statistic value. (Round your answer to two decimal places.) f = What can be said about the P-value for the test? O P-value > 0.100 O 0.050 < P-value < 0.100 O 0.010 < P-value < 0.050 O 0.001 < P-value < 0.010 O P-value < 0.001 State the conclusion in the problem context. O Reject Ho. There is not significant evidence…

In a population-based cohort study, an entire community was interviewed regarding smoking habits and then followed for one year. Upon ascertainment of all lung cancer deaths, the investigator obtained the following data:     Number of Individuals Lung Cancer Deaths Smokers 24,500 15 Nonsmokers 10,500 2   Calculate the risk difference per 100,000 per year. Round to the tenth decima

Two different analytical tests can be used to determine the impurity level in steel alloys. Eight specimens are tested using both procedures, and the results are shown in the following tabulation. Specimen 1 2 234 3 4 1.5 1.3 1.7 2.0 1.8 2.1 1.4 1.7 1.3 1.6 (a) Is a paired t-test appropriate for testing whether the means from the two tests are the same? Explain. (b) Is there sufficient evidence to conclude that tests differ in the mean impurity level, using a = 0.05? (c) Is there evidence to support the claim that test 1 generates a mean difference of 0.1 units lower than test 2? Use a = 0.01. Test 1 1.2 1.3 1.5 1.4 5 6 7 8 Test 2 1.4 1.7