Question: Briggs and Stratten make lawn mowers and are studying worker productivity. The variables are Y=time to assemble a certain part(in seconds), X₁ = 1 if experienced worker, 0 if inexperienced, X2 = age of the worker.

The regression equation is Y = 5 – 2X1 + .05X2, based on data from 25 workers.

a) Predict the time for an experienced, 35 year old worker.

b) If the t-stat for X1 is –6.55 is experience a good predictor of Y when

a=.10? Explain.