1. Chapter 10 Day 3 AP Statistics
Re-Expression con’t
Chapter 10 Day 3
AP Statistics

2. Concentration (Units/cc)
Warm Up
Time elapsed
(hours)
Concentration (Units/cc) 1 42 2 28 3 19 4 13 5 9 6 7
Penicillin
Assimilation
Straighten these data using re-expression
Use your model to estimate the concentration of penicillin after 8 hours

3. More Practice
Problems!

4. Brakes Explain why the linear model is not appropriate.
Speed
(mph)
Stopping
Distances (ft) 20 64 62 59 30
114
118
105 40
153
171
165 50
231
203
238 60
317
321
276
Explain why the linear model is not appropriate.
Re-express the data to straighten the scatterplot and give the re-expressed model.
Estimate stopping distance for a car traveling 55mph.

5. Population (millions)
Year
Population (millions)
1950
2519
1955
2755
1960
3020
1965
3334
1970
3691
1975
4066
1980
4430
1985
4825
1990
5255
1995
5662
2000
6057
World Population
Model (Scale the years)
Use your model to predict population for 2005.

6. What have we learned?
Recognize when a well-chosen re-expression may help you improve and simplify your analysis
Understand the value of re-expression to improve symmetry, to make scatter about the line more constant, and to make a plot more linear
Recognize that when a pattern indicates that no re-expression can improve the structure of the data

7. What have we learned?
Know how to re-express you data and how to use the calculator
Be able to reverse any common re-expressions to put a predicted value or residual back into the original units

8. What have we learned?
Be able to describe a summary or display of a re-expressed variable making clear how it was re-expressed and giving its re-expressed units.
Be able to describe a regression model fit to re-expressed data in terms of the re-expressed variables

9. Classwork Book Page 243 # 29

11. Homework
Page 241 # 24, 28, 30