- The Data And Summary Statistics Necessary To Answer The Questions Below Are Provided In The File Assignment3 R A Usi 1 (138.58 KiB) Viewed 55 times
# Sample mean of xxbar = mean(x)xbar
# Sample mean of yybar = mean(y)ybar
# Sum of squaressxx = sum((x - xbar)^2)sxx
syy = sum((y - ybar)^2)syy
sxy = sum((x - xbar)*(y - ybar))sxy
The data and summary statistics necessary to answer the questions below are provided in the file assignment3. R. (a) Using the formulas learnt in class, find the equation of the estimated regression line. For the value of b₁, leave your answers in 6 decimal places. Then, interpret the estimated intercept bo and the estimated slope b₁. (b) Compute the mean square error and hence the estimated standard error of the model ô. What does ô represent? (c) Using the formulas learnt in class, perform a model utility test. Your answer should include all the 6 steps learnt in class.
3 # remove objects in the environment 4 rm(list ls(all.names TRUE)) 5 6- ######; 7 # Data 8 X = c(9.67, 11.08, 12.54, 14.56, 16.43, 18.45, 19.03, 20.86, 23.43, 24.56, 26.44, 27.6, 28.4, 30.14, 31.62, 32.87, 33.79, 34.27, 35.21, 37.54) 9 y = c(20.52, 22.74, 23.53, 24.54, 26.75, 28.54, 31, 34.21, 36, 37.29, 41, 43.64, 46.43, 48.75, 50.32, 51.42, 53.23, 54.4, 57.23, 58.16) 11 # Sample mean of x 10 12 xbar = mean(x) 13 xbar 14 15 # Sample mean of y 16 ybar = mean(y) 17 ybar 18 19 #Sum of squares 20 SXX = sum((x 21 SXX 22 23 syy sum((y 24 syy 4 25 26 27 sxy = sum((x Sxy xbar)^2) - ybar)^2) = xbar)*(y - ybar)) ######