1. Bell Ringer
1. Write the equation of the regression line for the data. Explain the meaning of the y-intercept and the slope of the line.
2. A new burger containing 28 grams of fat is introduced. According to this model, how many calories does the burger have?
Fat (g) 19 31 34 35 39 43
Calories
410
580
590
570
640
680
660

2. Important notes for Chapter 9:
Beware of extrapolation! Extrapolation means using a linear model to make predictions for x-values outside of the range of given data.
Example: Using a model from this data to predict an error for the year 2065 would be extrapolation.

3. Leverage
A point with an x-value that is far from the mean of the x-values has a high leverage.

4. These points pull more strongly on the regression line.
If such a point is added in the path of the regression line, it won’t change the line, but it will strengthen r. It will also have a small residual.

5. Influential Points
A point is influential if removing it from the data set will give a very different linear model.

6. Today’s Assignment: Worksheet – Due before leaving
Read Chapters 9 & 10
Homework: p. 215 #1-3, 9, 12
If you missed the homework quiz, you must make it up by Wednesday – before or after school, or during 6th hour.