1. Some researchers were interested in comparing the effectiveness of three treatments for severe depression. For the sake of simplicity, we denote the three treatments A, B, and C. The researchers collected the following data on a random sample of n = 36 severely depressed individuals:

Y = measure of the effectiveness of the treatment

x₁= age (in years) of patient

x₂=1 if treatment A and 0 otherwise

x₃=1 if treatment B and 0 otherwise

2. Some researchers were interested in comparing the effectiveness of three treatments for severe depression. For the sake of simplicity, we denote the three treatments A, B, and C. The researchers collected the following data on a random sample of n = 36 severely depressed individuals: Y = measure of the effectiveness of the treatment X1= age (in years) of patient X2=1 if treatment A and 0 otherwise X3=1 if treatment B and 0 otherwise A crossed lines model was fit: E(Y) = Bo + B1X1 + B2x2 + B3x3 + B4X1X2 + 35X1X3 A scatterplot of the data, along with the three fitted lines from the model, are given below. Using the information given, find the fitted regression equation for the crossed lines model above. That is, find: bo, b1, b2, b3, b4, and b5, and then use these to write out the fitted equation. Show your work. Scatterplot of y vs age 80 TRT 1 = 47.5 +0.33x A 70 60 50 40 y = 28.9 + 0.52x 30 y = 6.21 + 1.03x 20 20 30 40 50 60 70