A)

It is believed that the impact of different fertilizers affect the growth of plants in different ways. To test this claim. a plant biologist randomly assigns 50 seedlings to a set of fertilizers. She measures the dry weight [in milligrams] of each seedling after a weeks in each group of fertilizers. Following is the ANDVA output for this example. Which of the following are true ? You may choose more than one answer. [if SL111 5a Mean Sq F yalue Pr-{a-FJ Fertilizer E 1?3.? 23.94? lab-9 Lila-El? **"' Residuals 343 1413+.E 4.395 Signif. codes: a unv .3331 \"In\" 91.31 '** 1.95 ill-1 ' ' l EEEEEE C] We do not reject HE} C] The results suggest that doing a multiple comparison analysis is worthwhile C] At least one group of seedlings had a signicantly different mean dry weight to at least one other group under 5% level of signicance C] The plant biologist considers 6 groups of fertilizers for this experiment C] The p_yalue of the test is {i when you round it to 3 decimal places A researcher was interested in comparing the effect of three treatments in reducing weight. To test the effect of the treatments, denoted Drug A, Drug B and Drug C, on weight loss, 150 patients were randomly allocated to receive either Drug A, Drug B or Drug C. After a month on the treatments, the weight loss measured in kilograms was recorded. The pairwise comparison of the weight loss for each drug is given below in the R output. Which of the following are true? You may choose more than one answer. # # Tukey multiple comparisons of means ## 95% family-wise confidence level ## ## Fit: aov(formula = Weight - Drug, data = WeightLoss) # # ## $Drug diff Lwr upr p adj ## DrugB-DrugA -0. 8131668 -1.7425919 0.1162583 0.0993320 ## DrugC-DrugA 0.6129746 -0.3164505 1.5423997 0.2656284 ## DrugC-DrugB 1.4261414 0. 4967163 2.3555665 0.0011191 O First row of this output represents a t-test to compare the population mean weight loss between patients who receive Drug B and Drug A Sample mean differences between each group are in the first column named diff O Patients who receive Drug C have a significantly different population mean weight loss to patients who receive Drug B under 5% level of significance Patients who receive Drug B have a significantly different population mean weight loss to patients who receive Drug A under 5% level of significance O Patients who receive Drug C have a significantly different population mean weight loss to patients who receive Drug A under 5% level of significanceOne study investigated the effects of musical genre on consumer spending. At a single high-end restaurant in Adelaide over a three-week period, there were a total of 136 participants; 42 of them were subjected to background pop music while dining, 50 to background classic music, and 44 to no background music. For each participant, the total food bill, adjusted for time spent dining, was recorded. The following table summarizes the standard deviations (in Australian dollars) Genre SD Classical 1.996 Pop 2.833 None 4.496 Which of the following is true for this example. O Linearity assumption is not satisfied. O Constant variance assumption is not satisfied O Linearity assumption is satisfied. O Constant variance assumption is satisfied O Independency assumption is not satisfied. Independency assumption is satisfied.Suppose we have a response variable y and a explanatoryr variable 1:. Consider the following linear regression line between A: and y: y = 1.452 + 4.0341 Which of the following are true? You mayr choose more than one answers. E] If x increases by one unit, then we expect v to increase by 4.D34 units E] x and v have a positive linear relationship E] If x is i] then we expect v to be 1.452 units E] If x is 3 then we expect v to be 13.554 units E] If x increases by one unit, then we expect v to increase by 1.452 units