Chapter 9.4, Problem 2P

(a)

To determine

Find the response variable.

Find the explanatory variables.

(b)

To determine

Find the constant term.

List the coefficients of explanatory variables.

(c)

To determine

Find the predicted value for $x_3$ if $x_1=10,x_4=-1,x_7=2$,

(d)

To determine

Find the expected change in $x_3$, if $x_1$ and $x_7$ are fixed but arbitrary values and $x_4$ was increased by 1 unit.

Find the expected change in $x_3$, if $x_1$ and $x_7$ are fixed but arbitrary values and $x_4$ was increased by 3 units.

Find the expected change in $x_3$, if $x_1$ and $x_7$ are fixed but arbitrary values and $x_4$ was decreased by 2 units.

(e)

To determine

Find the 90% confidence interval for coefficient $x_4$.

(f)

To determine

Test whether the coefficient of $x_4$ is different from zero or not.

Explain how the conclusion of test would affect the regression equation.