In Exercise 3.19, Consumer Reports gave the prices for the top 10 LCD high definition TVs (HDTVs) in the 30- to 40-inch category: Does the price of an LCD TV depend on the size of the screen? The table below shows the ten costs again, along with the screen size in inches.

Does the price of an HDTV depend on the size of the screen? Suppose we assume that the relationship between x and y is linear, and perform a linear regression, resulting in a value of r² = .787.

a. What does the value of r² tell you about the strength of the relationship between price and screen size?

b. The residual plot for this data, generated by MINITAB, is shown below. Does this plot reveal any outliers in the data set? If so, which point is the outlier?

c. Plot the values of x and y using a scatterplot. Does this plot confirm your suspicions in part b? Which HDTV does the outlier represent? Is this a faulty measurement that should be removed from the data set? Explain.

Transcribed Image Text:

Brand Price Size $2900 1800 JVC LT-40FH96 40 Sony Bravia KDL-V32XBR1 Sony Bravia KDL-V40XBR1 Toshiba 37HLX95 Sharp Aquos LC-32DA5U Sony Bravia KLV-S32A10 Panasonic Viera TC-32LX50 32 2600 40 3000 37 1300 32 1500 32 1350 32 JVC LT-37X776 2000 37 2200 LG 37LP1D 37 Samsung LN-R328W 1200 32 Residuals versus the Fitted Values (response is Price) 800 600- 400- 200- - 200 - -400 - 1500 1750 2000 2250 2500 2750 3000 Fitted Value Residual