3. Use the Wool data. Turn the three predictors len, amp, and load into factors and use log(cycles) as the response instead of cycles. Do the following:

a. Fit the model for log(cycles) using the three main effects and the three two-way interactions; report the type-II sum of squares ANOVA table. Which main effects and which interactions would you keep in the model, based on = 0.05?

b. Produce the effects plot for the full second-order model fit in part a. (Optional: Does it appear to be consistent with the test results you found in part a?)

c. Obtain estimates of the level means of amp in the model that only contains main effects using emmeans().

Wool<-

len amp load cycles 250 8 40 674 250 8 45 370 250 8 50 292 250 9 40 338 250 9 45 266 250 9 50 210 250 10 40 170 250 10 45 118 250 10 50 90 300 8 40 1414 300 8 45 1198 300 8 50 634 300 9 40 1022 300 9 45 620 300 9 50 438 300 10 40 443 300 10 45 332 300 10 50 220 350 8 40 3636 350 8 45 3184 350 8 50 2000

350 9 40 1568 350 9 45 1070 350 9 50 566 350 10 40 1140 350 10 45 884 350 10 50 360