January 2017
Beginner
882 pages
203h 41m
English
37. Diamond rings
β0 is an extrapolation, and b0 is about 15 se(b0) below zero. We expect a positive intercept, representing the fixed cost of the ring, though this is an extrapolation.
The prediction interval is [$607 to $735]. Because $800 lies above this interval, this ring is unusually expensive.
39. Download
Yes, we reject H0:ρ = 0 and H0:β1 = 0.
This is the confidence interval for the intercept, 3.9 to 10.7 sec.
6.5 to 9.2 seconds saved.
41. Seattle homes
Yes, data satisfy conditions of SRM.
b1 estimates fixed costs from $35,000 to $104,000.
b0 estimates marginal costs from 304 to 368 $/SqFt.
$180 to $540 per square foot.
$530,000 to more than $1.6 million.
43. R&D expenses
Estimated loge R&D = − 1.459 + 0.816 loge Total ...