Wednesday, October 07, 2009

Review answers

a) Yes! The residual plot shows no pattern
b) 233.5: For each year that goes by we predict about 233.5 more aircraft flying.
c) 89.9% of the variation in aircraft flying is explained by regression on year.
d) Plug in 2 (not 1992!): predicted aircraft = 2939.9+233.5*2 = 3406.9 aircraft.
e) residual at 2 = 40, so the actual was 3406.9+40=3446.9 or 3447
f) sqrt(.899) = .948 = strong, positive, linear relationship between year and aircraft.
g) On average, my predicted number of aircraft misses by about 33.43
h) aircraft-hat = 2939.93 + 233.5(year)
i) we predict in 1990 that the number of aircraft flying is about 2939.9

Study hard! I hope this helps!!!