# Question

In Exercise 13. 17, we considered a regression of y = oxygen consumption on x = time spent exercising. Summary quantities given there yield

a. Calculate sa1b12.02, the estimated standard deviation of the statistic a 1 b(2.0).

b. Without any further calculation, what is sa1b(3.0) and what reasoning did you use to obtain it?

c. Calculate the estimated standard deviation of the statistic a 1 b(2.8).

d. For what value x* is the estimated standard deviation of a 1 bx* smallest, and why? x

a. Calculate sa1b12.02, the estimated standard deviation of the statistic a 1 b(2.0).

b. Without any further calculation, what is sa1b(3.0) and what reasoning did you use to obtain it?

c. Calculate the estimated standard deviation of the statistic a 1 b(2.8).

d. For what value x* is the estimated standard deviation of a 1 bx* smallest, and why? x

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