Presentation on theme: "Chapter 10 Day 3 AP Statistics"— Presentation transcript:
1 Chapter 10 Day 3 AP Statistics Re-Expression con’tChapter 10 Day 3AP Statistics
2 Concentration (Units/cc) Warm UpTime elapsed(hours)Concentration (Units/cc)1422283194135967PenicillinAssimilationStraighten these data using re-expressionUse your model to estimate the concentration of penicillin after 8 hours
4 Brakes Explain why the linear model is not appropriate. Speed(mph)StoppingDistances (ft)2064625930114118105401531711655023120323860317321276Explain 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) YearPopulation (millions)1950251919552755196030201965333419703691197540661980443019854825199052551995566220006057World PopulationModel (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 analysisUnderstand the value of re-expression to improve symmetry, to make scatter about the line more constant, and to make a plot more linearRecognize 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 calculatorBe 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