Retail Price Data for N = 60 Hard Disk Drives $y =$

Essay

Retail price data for n = 60 hard disk drives were recently reported in a computer magazine. Three variables were recorded for each hard disk drive: $y =$ Retail PRICE (measured in dollars)
$x _ { 1 } =$ Microprocessor SPEED (measured in megahertz)
(Values in sample range from 10 to 40 )
$x _ { 2 } =$ CHIP size (measured in computer processing units)
(Values in sample range from 286 to 486)

A first-order regression model. was fit to the data. Part of the printout follows:

$\quad$ $\quad$ $\quad$ $\quad$ $\quad$$\quad$ $\quad$ $\quad$ $\quad$ $\quad$$\text { Parameter Estimates }$

$\quad$ $\quad$ $\quad$$\text { PARAMETER STANDARD\quad\quad\quad\quad T FOR 0: }$
$\text { VARIABLE DF ESTIMATE } \quad \text { ERROR PARAMETER }=0 \mathrm{PROB}>|\mathrm{T}|$
$\begin{array}{lrllll}\text { INTERCEPT } & 1 & -373.526392 & 1258.1243396 & -0.297 & 0.7676 \\\text { SPEED } & 1 & 104.838940 & 22.36298195 & 4.688 & 0.0001 \\\text { CHIP } & 1 & 3.571850 & 3.89422935 & 0.917 & 0.3629\end{array}$
Identify and interpret the estimate of $\beta _ { 2 }$ .