# Color-Coded Linear Regression (Intro)

The applet below displays 10 points plotted in the coordinate plane. It also displays (what's called) the best-fit-line for these 10 points. Shown also is a number we call the correlation coefficient (r). You can drag these points anywhere you'd like. As you do, watch what happens. Interact with this applet for a few minutes. Then, answer the questions that follow.

## 1.

Reposition (rearrange) all 10 points so that the correlation coefficient (r) = +1. How would you describe the position(s) of these points? Be specific!

## 2.

Reposition (rearrange) all 10 points so that the correlation coefficient (r) = -1. How would you describe the position(s) of these points? Be specific!

## 3.

Can you drag the points around so the correlation coefficient of the best fit line is zero? Try it.

## 4.

Try to position the point(s) anywhere so that the correlation coefficient r is between 0.90 and 1.00. Describe what you see.

## 5.

Repeat question (4) a few times, but this time try to make r a) between 0.80 and 0.90 b) between 0.50 and 0.60 c) between 0.20 and 0.30 Can you make any generalizations based upon what you see?

## 6.

Try to position the point(s) anywhere so that the correlation coefficient r is between -1.00 and -0.90. Describe what you see.

## 7.

Repeat question (6) a few times, but this time try to make r a) between -0.90 and -0.80 b) between -0.60 and -0.50 c) between -0.30 and -0.20 Can you make any generalizations based upon what you see?