Page 17 - Intermediate Statistics for Dummies

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Intermediate Statistics For Dummies
Using the Best Subsets Procedure.............................................................123
Forming all models and choosing the best one..............................123
Applying best subsets to the punt distance example....................124
Comparing Model Selection Procedures...................................................126
Why don’t all the procedures get the same results? .....................126
How do the procedures stack up against each other? ..................127
Chapter 7: When Data Throws You a Curve: Using
Nonlinear Regression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .129
Starting Out with Scatterplots....................................................................130
Handling Curves in the Road with Polynomials.......................................131
Bringing back polynomials................................................................132
Searching for the best polynomial model .......................................134
Using a second-degree polynomial to pass the quiz......................135
Assessing the fit of a polynomial model..........................................137
Making predictions.............................................................................140
Going Up? Going Down? Go Exponential!..................................................142
Recollecting exponential models .....................................................142
Searching for the best exponential model ......................................143
Spreading secrets at an exponential rate........................................145
Chapter 8: Yes, No, Maybe So: Making Predictions By
Using Logistic Regression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .149
Setting Up the Logistic Regression Model ................................................149
Defining a logistic regression model................................................150
Using an S-curve to estimate probabilities .....................................150
Interpreting the coefficients of the logistic regression model .....151
Estimating the chance a movie will be a hit by using logistic
regression ........................................................................................151
General Steps for Logistic Regression.......................................................152
Running the analysis in Minitab .......................................................153
Finding the coefficients and making the model..............................154
Estimating p ........................................................................................155
Checking the fit of the model............................................................156
Part III: Comparing Many Means with ANOVA ............159
Chapter 9: Going One-Way with Analysis of Variance . . . . . . . . . . . .161
Comparing Two Means with a t-Test .........................................................162
Evaluating More Means with ANOVA.........................................................163
Spitting seeds: A situation just waiting for ANOVA........................163
Walking through the steps of ANOVA ..............................................164