Answer Happy

Unless otherwise stated, carry out inferences using a = 0.05. Hypotheses should be written in terms of parameters when possible, and conclusions of hypothesis tests should be given using the context of the problem. A new video hosting platform has been trying to recruit content creators. The platform earns money every time a viewer subscribes to a given channel, but the platform has to pay web hosting fees for every video supported by the platform. The file web hosting.txt contains data on 72 channels. The Earnings column contains the average monthly channel earnings (which may be negative) in thousands of dollars. The Length column gives the average length of a video on the channel, in minutes. Finally, a column labeled Group classifies a particular channel with the label I, II, or III. a) Ensure that you have read in all the data by reproducing the sample mean of the Earnings column as 8.8151. b) Suppose we wish to model Earnings as a linear function of Length, Group, and their interaction. State the regression model using mathematical symbols. c) Explain (using mathematical symbols) how Minitab will deal with the Group variable when instructed to fit a linear model and estimate parameters via least squares. d) Write a set of expressions (using mathematical symbols) for the expected value of Y; one for each possible value of X2. e) Fit the full model in Minitab; provide the coefficients table and the ANOVA table.
Earnings Length Group 30.82 54.5 III 8.26 51.46 II 31.87 38.74 III 6.49 53.64 II -16.1 44.53 I 3.17 53.13 II 5.84 43.4 II 29.82 54.92 III 21.02 43.99 III -15.45 48.31 I 25.05 46.6 III -25.31 47.68 I -4.76 44.87 I 10.17 53.15 II 11.8955.32 II -16.62 43.21 I 24.02 37.07 III 11.87 46.49 II -0.7 47.91 II 21.35 44.64 III 28.89 43.58 III 25.53 48.66 III -17.25 54.98 I 24.8 48.33 III 31.44 50.41 III