A correlation analysis of the exchange of greeting cards by five friends for the most recent holiday season suggests a strong positive relationship between cards given and cards received. When informed of these results, another friend, Emma, who greatly enjoys receiving cards, asks you to predict how many cards she will receive during the next holiday season, assuming that she plans to send 11 cards.

10.1 TWO ROUGH PREDICTIONS

Predict "Relatively Large Number"

You could offer Emma a very rough prediction by recalling that cards given and received tend to occupy similar relative locations in their respective distributions. Looking at these distributions, Emma can expect to receive a relatively large number of cards, as she plans to send a relatively large number of cards.

Predict "between 14 and 18 cards"

To obtain a slightly more precise prediction for Emma, refer to the scatter-plot for the original five friends shown in Figure...