When'sDay

Today in class we started our chapter 9 notes...

• Discussed interpolation vs. extrapolation
• Re-defined what an outlier is in a scatterplot
• Defined and discussed leverage
• Use last night's homework to determine if a point is influential (continued with tonight's hw)

Tonight, please complete the worksheet provided in class (starting with question 6); question 6 is a continuation of last night's homework. For the "reading questions," use your textbook to look up each answer!

If you lost yours or you were absent, here are the questions!

• **1-5 were last night's homework
• **6 and the reading questions are tonight's homework!

1.       Sketch a scatterplot and a residual plot for the data provided in the space below. Label your axes for each.

2.       Calculate the correlation coefficient, coefficient of determination, and the equation of the LSRL.

3.       Add the point  (1977,24) to your data (and your scatterplot above). Now record the correlation, coefficient of determination, and regression equation.

4.       Remove this point (1977,24). Instead, add (2010,22.5). Record the correlation, coefficient of determination, and regression equation.

5.       Remove this point (2010,22.5). Instead, add (1968,18). Record the correlation, coefficient of determination, and regression equation.

6.       Which point had the most influence on the equation of the line of best fit? Explain your reasoning referencing each of the statistics calculated above.

 (1977,24)

(2010,22.5)

(1968,18)

Chapter 9 Reading Questions (look these up in your notes and/or your textbook!)

1.       In your own words, what is extrapolation?

2.       In your own words, define leverage.

3.       What does it mean for a point to be influential?

4.       How can we define an outlier in a scatterplot?

5.       Define lurking variable.

 

Also, here is tomorrow's homework (in the textbook) in case you'd like to get ahead:

Thursday HW: Page 213: 1, 7, 9