The Statistical Sleuth A Course in Methods of Data Analysis

by Ramsey, Fred; Schafer, Daniel

• ISBN13: 9780534386702
• ISBN10: 0534386709
• Edition: 2nd
• Format: Hardcover
• Copyright: 2001-10-05
• Publisher: Duxbury Press

Summary

STATISTICAL SLEUTH is an innovative treatment of general statistical methods, taking full advantage of the computer, both as a computational and an analytical tool. The material is independent of any specific software package. In "The American Statistician" (February 2000, Vol. 54, No. 1), George Cobb commented, "What is new and different about Ramsey and Schafer's book, what makes it a 'larger contribution,' is that it gives much more prominence to modeling and interpretation of the sort that goes beyond the routine patterns." His students did "substantially better" on term papers based on the analysis of data. In the book, the focus is on a serious analysis of real case studies; on strategies and tools of modern statistical data analysis; on the interplay of statistics and scientific learning; and on the communication of results. With interesting examples, real data, and a variety of exercise types (conceptual, computational, and data problems), the authors get students excited about statistics.

Table of Contents

Drawing Statistical Conclusions	1	(27)
Case Studies	2	(3)
Motivation and Creativity--A Randomized Experiment	2	(2)
Sex Discrimination in Employment--An Observational Study	4	(1)
Statistical Inference and Study Design	5	(5)
Causal Inference	5	(2)
Inference to Populations	7	(1)
Statistical Inference and Chance Mechanisms	8	(2)
Measuring Uncertainty in Randomized Experiments	10	(4)
A Probability Model for Randomized Experiments	10	(1)
A Test for Treatment Effect in the Creativity Study	11	(3)
Measuring Uncertainty in Observational Studies	14	(2)
A Probability Model for Random Sampling	14	(1)
Testing for a Difference in the Sex Discrimination Study	15	(1)
Related Issues	16	(6)
Graphical Methods	16	(4)
Standard Statistical Terminology	20	(1)
Randomization of Experimental Units to Treatments	21	(1)
Selecting a Simple Random Sample from a Population	21	(1)
On Being Representative	22	(1)
Summary	22	(1)
Exercises	22	(6)
Conceptual Exercises	22	(2)
Computational Exercises	24	(2)
Answers to Conceptual Exercises	26	(2)
Inference Using t Distributions	28	(28)
Case Studies	29	(2)
Bumpus's Data on Natural Selection--An Observational Study	29	(1)
Anatomical Abnormalities Associated with Schizophrenia--An Observational Study	30	(1)
One-Sample t-Tools and the Paired t-Test	31	(6)
The Sampling Distribution of a Sample Average	31	(2)
The Standard Error of an Average in Random Sampling	33	(1)
The t-Ratio Based on a Sample Average	34	(1)
Unraveling the t-Ratio	35	(2)
A t-Ratio for Two-sample Inference	37	(7)
Sampling Distribution of the Difference Between Two Independent Sample Averages	38	(1)
Standard Error for the Difference of Two Averages	39	(1)
Confidence Interval for the Difference Between Population Means	40	(2)
Testing a Hypothesis About the Difference Between Means	42	(1)
The Mechanics of p - Value Computation	43	(1)
Inferences in a Two-Treatment Randomized Experiment	44	(2)
Approximate Uncertainty Measures for Randomized Experiments	45	(1)
Related Issues	46	(3)
Interpretation of p - Values	46	(1)
An Example of Confidence Intervals	47	(2)
The Rejection Region Approach to Hypothesis Testing	49	(1)
Summary	49	(1)
Exercises	50	(6)
Conceptual Exercises	50	(1)
Computational Exercises	51	(1)
Data Problems	52	(2)
Answers to Conceptual Exercises	54	(2)
A Closer Look at Assumptions	56	(29)
Case Studies	57	(3)
Cloud Seeding to Increase Rainfall--A Randomized Experiment	57	(1)
Effects of Agent Orange on Troops in Vietnam--An Observational Study	58	(2)
Robustness of the Two-Sample t-Tools	60	(4)
The Meaning of Robustness	60	(1)
Robustness Against Departures from Normality	60	(2)
Robustness Against Differing Standard Deviations	62	(1)
Robustness Against Departures from Independence	62	(2)
Resistance of the Two-Sample t-Tools	64	(1)
Outliers and Resistance	64	(1)
Resistance of t-Tools	65	(1)
Practical Strategies for the Two-Sample Problem	65	(3)
Transformations of the Data	68	(5)
The Logarithmic Transformation	68	(1)
Interpretation After a Log Transformation	69	(3)
Other Transformations for Positive Measurements	72	(1)
Related Issues	73	(1)
Prefer Graphical Methods Over Formal Tests for Model Adequacy	73	(1)
Robustness and Transformation for Paired t-Tools	73	(1)
Example--Schizophrenia	74	(1)
Summary	74	(1)
Exercises	75	(10)
Conceptual Exercises	75	(2)
Computational Exercises	77	(4)
Data Problems	81	(1)
Answers to Conceptual Exercises	82	(3)
Alternatives to the t-Tools	85	(28)
Case Studies	86	(3)
Space Shuttle O-Ring Failures--An Observational Study	86	(1)
Cognitive Load Theory in Teaching--A Randomized Experiment	87	(2)
The Rank-Sum Test	89	(6)
The Rank Transformation	89	(1)
The Rank-Sum Statistic	90	(1)
Finding a p - Value by Normal Approximation	90	(3)
A Confidence Interval Based on the Rank-Sum Test	93	(2)
Other Alternatives for Two Independent Samples	95	(4)
Permutation Tests	95	(2)
The Welch t-Test for Comparing Two Normal Populations with Unequal Spreads	97	(2)
Alternatives for Paired Data	99	(2)
The Sign Test	99	(1)
The Wilcoxon Signed-Rank Test	100	(1)
Related Issues	101	(3)
Practical and Statistical Significance	101	(1)
The Presentation of Statistical Findings	102	(1)
Levene's Test for Equality of Two Variances	102	(1)
Survey Sampling	103	(1)
Summary	104	(1)
Exercises	105	(8)
Conceptual Exercises	105	(1)
Computational Exercises	106	(2)
Data Problems	108	(3)
Answers to Conceptual Exercises	111	(2)
Comparisons Among Several Samples	113	(36)
Case Studies	114	(5)
Diet Restriction and Longevity--A Randomized Experiment	114	(3)
The Spock Conspiracy Trial--An Observational Study	117	(2)
Comparing Any Two of the Several Means	119	(2)
An Ideal Model for Several-Sample Comparisons	119	(1)
The Pooled Estimate of the Standard Deviation	120	(1)
t-Tests and Confidence Intervals for Differences of Means	120	(1)
The One-Way Analysis of Variance F-Test	121	(6)
The Extra-Sum-of Squares Principle	121	(5)
The Analysis of Variance Table for One-Way Classification	126	(1)
More Applications of the Extra-Sum-of-Squares F-Test	127	(3)
Example: Testing Equality in a Subset of Groups	127	(2)
Summary of ANOVA Tests Involving More Than Two Models	129	(1)
Robustness and Model Checking	130	(3)
Robustness to Assumptions	130	(1)
Diagnostics Using Residuals	131	(2)
Related Issues	133	(7)
Further Illustration of the Different Sources of Variability	133	(3)
Kruskal-Wallis Nonparametric Analysis of Variance	136	(1)
Random Effects	136	(2)
Separate Confidence Intervals and Significant Differences	138	(2)
Summary	140	(1)
Exercises	141	(8)
Conceptual Exercises	141	(1)
Computational Exercises	141	(5)
Data Problems	146	(1)
Answers to Conceptual Exercises	147	(2)
Linear Combinations and Multiple Comparisons of Means	149	(25)
Case Studies	150	(2)
Discrimination Against the Handicapped-A Randomized Experiment	150	(1)
Preexisting Preferences of Fish-A Randomized Experiment	151	(1)
Inferences About Linear Combinations of Group Means	152	(7)
Linear Combinations of Group Means	152	(2)
Inferences About Linear Combinations of Group Means	154	(2)
Specific Linear Combinations	156	(3)
Simultaneous Inferences	159	(2)
Some Multiple Comparison Procedures	161	(4)
Tukey-Kramer Procedure and the Studentized Range Distributions	161	(1)
Scheffe's Procedure	162	(1)
Other Multiple Comparisons Procedures	162	(1)
Multiple Comparisons in the Handicap Study	163	(1)
Choosing a Multiple Comparisons Procedure	164	(1)
Related Issues	165	(3)
Fishing Expeditions with Many Response Measurements	165	(1)
Example of a Hypothesis Based on How the Data Turned Out	165	(2)
Is Choosing a Transformation a Form of Data Snooping?	167	(1)
Summary	168	(1)
Exercises	168	(6)
Conceptual Exercises	168	(1)
Computational Exercises	169	(2)
Data Problems	171	(1)
Answers to Conceptual Exercises	172	(2)
Simple Linear Regression: A Model for the Mean	174	(32)
Case Studies	175	(3)
The Big Bang--An Observational Study	175	(2)
Meat Processing and pH--A Randomized Experiment	177	(1)
The Simple Linear Regression Model	178	(3)
Regression Terminology	178	(1)
Interpolation and Extrapolation	179	(2)
Least Squares Regression Estimation	181	(5)
Fitted Values and Residuals	181	(1)
Least Squares Estimators	182	(1)
Sampling Distributions of the Least Squares Estimators	182	(1)
Estimation of σ from Residuals	182	(2)
Standard Errors	184	(2)
Inferential Tools	186	(6)
Tests and Confidence Intervals for Slope and Intercept	186	(1)
Describing the Distribution of the Response Variable at Some Value of the Explanatory Variable	186	(3)
Prediction of a Future Response	189	(1)
Calibration: Estimating the X that Results in Y = Y0	190	(2)
Related Issues	192	(3)
Historical Notes About Regression	192	(1)
Differing Terminology	193	(1)
Causation	194	(1)
Correlation	194	(1)
Planning an Experiment: Replication	195	(1)
Summary	195	(1)
Exercises	196	(10)
Conceptual Exercises	196	(1)
Computational Exercises	196	(6)
Data Problems	202	(3)
Answers to Conceptual Exercises	205	(1)
A Closer Look at Assumptions for Simple Linear Regression	206	(29)
Case Studies	207	(3)
Island Area and Number of Species--An Observational Study	207	(1)
Breakdown Times for Insulating Fluid Under Different Voltages--A Controlled Experiment	208	(2)
Robustness of Least Squares Inferences	210	(2)
Graphical Tools for Model Assessment	212	(3)
Scatterplot of the Response Variable Versus the Explanatory Variable	212	(2)
Scatterplots of Residuals Versus Fitted Values	214	(1)
Interpretation After Log Transformations	215	(2)
Assessment of Fit Using the Analysis of Variance	217	(4)
Three Models for the Population Means	217	(1)
The Analysis of Variance Table Associated with Simple Regression	217	(2)
The Lack-of Fit F-Test	219	(1)
A Composite Analysis of Variance Table	219	(2)
Related Issues	221	(4)
R-Squared: The Proportion of Variation Explained	221	(1)
Simple Linear Regression or One-Way Analysis of Variance?	222	(1)
Other Residual Plots for Special Situations	223	(1)
Planning an Experiment: Balance	224	(1)
Summary	225	(1)
Exercises	226	(9)
Conceptual Exercises	226	(1)
Computational Exercises	227	(3)
Data Problems	230	(3)
Answers to Conceptual Exercises	233	(2)
Multiple Regression	235	(32)
Case Studies	236	(4)
Effects of Light on Meadowfoam Flowering--A Randomized Experiment	236	(1)
Why Do Some Mammals Have Large Brains for Their Size?--An Observational Study	237	(3)
Regression Coefficients	240	(3)
The Multiple Linear Regression Model	240	(1)
Interpretation of Regression Coefficients	241	(2)
Specially Constructed Explanatory Variables	243	(7)
A Squared Term for Curvature	244	(1)
An Indicator Variable to Distinguish Between Two Groups	245	(1)
Sets of Indicator Variables for Categorical Explanatory Variables with More Than Two Categories	246	(1)
A Product Term for Interaction	247	(2)
A Shorthand Notation for Model Description	249	(1)
A Strategy for Data Analysis	250	(1)
Graphical Methods for Data Exploration and Presentation	251	(5)
A Matrix of Pairwise Scatterplots	251	(3)
Coded Scatterplots	254	(1)
Jittered Scatterplots	255	(1)
Trellis Graphs	255	(1)
Related Issues	256	(1)
Computer Output	256	(1)
Factorial Treatment Arrangement	257	(1)
Summary	257	(1)
Exercises	258	(9)
Conceptual Exercises	258	(2)
Computational Exercises	260	(4)
Data Problems	264	(1)
Answers to Conceptual Exercises	265	(2)
Inferential Tools for Multiple Regression	267	(37)
Case Studies	268	(3)
Galileo's Data on the Motion of Falling Bodies--A Controlled Experiment	268	(1)
The Energy Costs of Echolocation by Bats--An Observational Study	269	(2)
Inferences About Regression Coefficients	271	(9)
Least Squares Estimates and Standard Errors	271	(2)
Tests and Confidence Intervals for Single Coefficients	273	(2)
Tests and Confidence Intervals for Linear Combinations of Coefficients	275	(4)
Prediction	279	(1)
Extra-Sums-of-Squares F-Tests	280	(5)
Comparing Sizes of Residuals in Hierarchical Models	280	(1)
F-Test for the Joint Significance of Several Terms	281	(1)
The Analysis of Variance Table	282	(3)
Related Issues	285	(6)
Further Notes on the R-Squared Statistic	285	(2)
Improving Galileo's Design with Replication	287	(1)
Variance Formulas for Linear Combinations of Regression Coefficients	288	(2)
Further Notes About Polynomial Regression	290	(1)
Finding Where the Mean Response is at its Maximum in Quadratic Regression	290	(1)
The Principle of Occam's Razor	290	(1)
Informal Tests in Model Fitting	291	(1)
Summary	291	(1)
Exercises	292	(12)
Conceptual Exercises	292	(2)
Computational Exercises	294	(5)
Data Problems	299	(3)
Answers to Conceptual Exercises	302	(2)
Model Checking and Refinement	304	(34)
Case Studies	305	(5)
Alcohol Metabolism in Men and Women--An Observational Study	305	(2)
The Blood-Brain Barrier--A Controlled Experiment	307	(3)
Residual Plots	310	(3)
A Strategy for Dealing with Influential Observations	313	(3)
Case-Influence Statistics	316	(5)
Leverages for Flagging Cases with Unusual Explanatory Variable Values	316	(2)
Studentized Residuals for Flagging Outliers	318	(1)
Cook's Distances for Flagging Influential Cases	319	(1)
A Strategy for Using Case Influence Statistics	320	(1)
Refining the Model	321	(7)
Testing Terms	321	(2)
Partial Residual Plots	323	(5)
Related Issues	328	(2)
Weighted Regression for Certain Types of Nonconstant Variance	328	(1)
The Delta Method	328	(1)
Measurement Errors in Explanatory Variables	329	(1)
Summary	330	(1)
Exercises	331	(7)
Conceptual Exercises	331	(1)
Computational Exercises	332	(3)
Data Problems	335	(2)
Answers to Conceptual Exercises	337	(1)
Strategies for Variable Selection	338	(36)
Case Studies	339	(6)
State Average SAT Scores-An Observational Study	339	(3)
Sex Discrimination in Employment-An Observational Study	342	(3)
Specific Issues Relating to Many Explanatory Variables	345	(5)
Objectives	345	(2)
Loss of Precision	347	(1)
A Strategy for Dealing with Many Explanatory Variables	347	(3)
Sequential Variable Selection Techniques	350	(4)
Forward Selection	350	(1)
Backward Elimination	350	(1)
Stepwise Regression	351	(1)
Sequential Variable Selection with the SAT Data	351	(2)
Compounded Uncertainty in Stepwise Procedures	353	(1)
Model Selection Among All Subsets	354	(4)
The Cp Statistic and Cp Plot	355	(1)
Akaike's and the Bayes Information Criteria	356	(2)
Posterior Beliefs About Different Models	358	(1)
Analysis of the Sex Discrimination Data	358	(4)
Related Issues	362	(4)
The Trouble with Interpreting Significance When Explanatory Variables Are Correlated	362	(2)
Regression for Adjustment and Ranking	364	(1)
Saturated Second-Order Models	365	(1)
Cross Validation	366	(1)
Summary	366	(1)
Exercises	367	(7)
Conceptual Exercises	367	(1)
Computational Exercises	368	(2)
Data Problems	370	(2)
Answers to Conceptual Exercises	372	(2)
The Analysis of Variance for Two-Way Classifications	374	(35)
Case Studies	375	(3)
Intertidal Seaweed Grazers--A Randomized Experiment	375	(2)
The Pygmalion Effect--A Randomized Experiment	377	(1)
Additive and Nonadditive Models for Two-Way Tables	378	(4)
The Additive Model	378	(1)
The Saturated, Nonadditive Model	378	(4)
A Strategy for Analyzing Two-Way Tables with Several Observations per Cell	382	(1)
The Analysis of Variance F-Test for Additivity	382	(1)
Analysis of the Seaweed Grazer Data	382	(10)
Initial Assessment of Additivity, Outliers, and the Need for Transformation	382	(2)
The Analysis of Variance Table from the Fit to the Saturated Model	384	(2)
The Analysis of Variance Table for the Fit to the Additive Model	386	(2)
Answers to Specific Questions of Interest Using Linear Combinations	388	(2)
Answers to Specific Questions of Interest Using Multiple Regression with Indicator Variables	390	(2)
Analysis of the Pygmalion Data	392	(6)
Initial Exploration and Check on Additive Model	392	(3)
Answering the Question of Interest with Regression	395	(1)
A Closer Look at the Regression Estimate of Treatment Effect	396	(1)
The p-Value in the Randomization Distribution	397	(1)
Related Issues	398	(5)
Additivity and Nonadditivities	398	(2)
Orthogonal Contrasts	400	(1)
Randomized Blocks and Paired-t Analyses	401	(1)
Should Insignificant Block Effects be Eliminated from the Model?	401	(1)
Multiple Comparisons	401	(1)
An Alternate Parameterization for the Additive Model	401	(2)
Summary	403	(1)
Exercises	404	(5)
Conceptual Exercises	404	(1)
Computational Exercises	404	(3)
Data Problems	407	(1)
Answers to Conceptual Exercises	408	(1)
Multifactor Studies Without Replication	409	(27)
Case Studies	410	(4)
Chimpanzees Learning Sign Language--A Controlled Experiment	410	(1)
Effects of Ozone in Conjunction with Sulfur Dioxide and Water Stress on Soybean Yield--A Randomized Experiment	411	(3)
Strategies for Analyzing Tables with One Observation per Cell	414	(1)
Rationale for Designs with One Observation per Cell	414	(1)
Strategy for Data Analysis in the Absence of Replicates	415	(1)
Analysis of the Chimpanzee Learning Times Study	415	(6)
Analysis of the Soybean Data	421	(6)
Exploratory Analysis	422	(4)
Answering Questions of Interest with the Fitted Models	426	(1)
Related Issues	427	(4)
Random Effects Models	427	(1)
Nested Classifications in the Analysis of Variance	428	(1)
Further Rationale for One Observation per Cell	429	(2)
Uniformity Trials	431	(1)
Summary	431	(1)
Exercises	432	(4)
Conceptual Exercises	432	(1)
Computational Exercises	432	(1)
Data Problems	433	(2)
Answers to Conceptual Exercises	435	(1)
Adjustment for Serial Correlation	436	(26)
Case Studies	437	(2)
Logging Practices and Water Quality--An Observational Study	437	(1)
Measuring Global Warming--An Observational Study	438	(1)
Comparing the Means of Two Time Series	439	(6)
Serial Correlation and Its Effect on the Average of a Time Series	440	(2)
The Standard Error of an Average in a Serially Correlated Time Series	442	(1)
Estimating the First Serial Correlation Coefficient	442	(2)
Pooling Estimates and Comparing Means of Two Independent Time Series with the Same First Serial Correlation	444	(1)
Regression After Transformation in the AR(1) Model	445	(3)
The Serial Correlation Coefficient Based on Regression Residuals	445	(1)
Regression with Filtered Variables	445	(3)
Determining if Serial Correlation is Present	448	(2)
An Easy, Large-Sample Test for Serial Correlation	448	(1)
The Nonparametric Runs Test	448	(2)
Diagnostic Procedures for Judging the Adequacy of the AR(1) Model	450	(4)
When Is a Transformation of a Time Series Indicated?	450	(1)
The Partial Autocorrelation Function (PACF)	450	(3)
Bayesian Information Criterion	453	(1)
Related Issues	454	(1)
Time Series Analysis is a Large-Sample Game	454	(1)
The Autocorrelation Function	454	(1)
Time Series Without a Time Series Package	454	(1)
Negative Serial Correlation	454	(1)
Summary	455	(1)
Exercises	456	(6)
Conceptual Exercises	456	(1)
Computational Exercises	456	(2)
Data Problems	458	(3)
Answers to Conceptual Exercises	461	(1)
Repeated Measures and Other Multivariate Responses	462	(35)
Case Studies	463	(3)
Sites of Short- and Long-Term Memory--A Controlled Experiment	463	(1)
Oat Bran and Cholesterol--A Randomized Crossover Experiment	464	(2)
Tools and Strategies for Analyzing Repeated Measures	466	(5)
Types of Repeated Measures Studies	467	(1)
Profile Plots for Graphical Exploration	468	(1)
Strategies for Analyzing Repeated Measures	468	(3)
Comparing the Means of Bivariate Responses in Two Groups	471	(8)
Summary Statistics for Bivariate Responses	471	(2)
Pooled Variability Estimates	473	(1)
Hotelling's T2 Statistic	474	(1)
Checking on Assumptions	475	(1)
Confidence Ellipses and Individual Confidence Intervals for Differences in Bivariate Means	476	(3)
One-Sample Analysis with Bivariate Responses	479	(4)
Treatment Differences in the Oat Bran Study	479	(1)
Summary Statistics for a Single Sample of Bivariate Responses	480	(1)
Hotelling's T2 Test that the Means of a Bivariate Response are Both Zero	480	(1)
Checking on Assumptions	481	(2)
Related Issues	483	(3)
Two-Sample Analysis with More Than Two Responses	483	(1)
One-Sample Analysis with More Than Two Responses	484	(1)
Multivariate Regression and Multivariate Analysis of Variance (MANOVA)	484	(1)
Planned and Unplanned Summaries of Multivariate Measurements as Response Variables	484	(1)
Planning an Experiment: Benefits of Repeated Measurements	485	(1)
Related Issues	486	(2)
Notes Concerning Correlation	486	(2)
Star Plots for Multivariate Responses	488	(1)
Summary	488	(1)
Exercises	489	(8)
Conceptual Exercises	489	(1)
Computational Exercises	490	(4)
Data Problems	494	(2)
Answers to Conceptual Exercises	496	(1)
Exploratory Tools for Summarizing Multivariate Responses	497	(32)
Case Studies	498	(4)
Magnetic Force on Rods in Printers--A Controlled Experiment	498	(2)
Love and Marriage--An Observational Study	500	(2)
Linear Combinations of Variables	502	(2)
Principal Components Analysis	504	(7)
The PCA Train	504	(1)
Principal Components	504	(3)
Variables Suggested by PCA	507	(2)
Scatterplots in Principal Component Space	509	(1)
The Factor Analysis Model and Principal Components Analysis	510	(1)
PCA Usage	510	(1)
Canonical Correlations Analysis	511	(4)
Canonical Variables	511	(2)
Variables Suggested by CCA	513	(1)
Love and Marriage Example	513	(2)
Introduction to Other Multivariate Tools	515	(6)
Discriminant Function Analysis (DFA)	515	(1)
Cluster Analysis	516	(1)
Multidimensional Scaling	517	(1)
Correspondence Analysis	518	(1)
PCA and Empirical Orthogonal Functions (EOFs)	519	(2)
Summary	521	(1)
Exercises	522	(7)
Conceptual Exercises	522	(2)
Computational Exercises	524	(1)
Data Problems	525	(3)
Answers to Conceptual Exercises	528	(1)
Comparisons of Proportions or Odds	529	(23)
Case Studies	530	(3)
Obesity and Heart Disease--An Observational Study	530	(1)
Vitamin C and the Common Cold--A Randomized Experiment	531	(1)
Smoking and Lung Cancer--A Retrospective Observational Study	532	(1)
Inferences for the Difference of Two Proportions	533	(5)
The Sampling Distribution of a Sample Proportion	533	(2)
Sampling Distribution for the Difference between Two Sample Proportions	535	(1)
Inferences about the Difference between Two Population Proportions	536	(2)
Inference About the Ratio of Two Odds	538	(4)
A Problem with the Difference between Proportions	538	(1)
Odds	539	(1)
The Ratio of Two Odds	539	(2)
Sampling Distribution of the Log of the Estimated Odds Ratio	541	(1)
Inference from Retrospective Studies	542	(3)
Retrospective Studies	542	(2)
Why the Odds Ratio Is the Only Appropriate Parameter if the Sampling Is Retrospective	544	(1)
Summary	545	(1)
Exercises	546	(6)
Conceptual Exercises	546	(2)
Computational Exercises	548	(2)
Data Problems	550	(1)
Answers to Conceptual Exercises	550	(2)
More Tools for Tables of Counts	552	(27)
Case Studies	553	(2)
Sex Role Stereotypes and Personnel Decisions--A Randomized Experiment	553	(1)
Death Penalty and Race of Murder Victim--An Observational Study	554	(1)
Population Models for 2 x 2 Tables of Counts	555	(4)
Hypotheses of Homogeneity and of Independence	555	(1)
Sampling Schemes Leading to 2 x 2 Tables	556	(2)
Testable Hypotheses and Estimable Parameters	558	(1)
The Chi-Squared Test	559	(3)
The Pearson Chi-Squared Test for Goodness of Fit	559	(1)
Chi-Squared Test of Independence in a 2 x 2 Table	559	(1)
Equivalence of Several Tests for 2 x 2 Tables	560	(2)
Fisher's Exact Test: The Randomization (Permutation) Test for 2 x 2 Tables	562	(4)
The Randomization Distribution of the Difference in Sample Proportions	562	(2)
The Hypergeometric Formula for One-Sided p-Values	564	(1)
Fisher's Exact Test for Observational Studies	564	(1)
Fisher's Exact Test Versus Other Tests	564	(2)
Combining Results from Several Tables with Equal Odds Ratios	566	(4)
The Mantel-Haenszel Excess	566	(1)
The Mantel-Haenszel Test for Equal Odds in Several 2 x 2 Tables	567	(2)
Estimate of the Common Odds Ratio	569	(1)
Related Issues	570	(1)
r x c Tables of Counts	570	(1)
Higher-Dimensional Tables of Counts	570	(1)
Summary	571	(1)
Exercises	572	(7)
Conceptual Exercises	572	(1)
Computational Exercises	573	(3)
Data Problems	576	(1)
Answers to Conceptual Exercises	577	(2)
Logistic Regression for Binary Response Variables	579	(30)
Case Studies	580	(3)
Survival in the Donner Party--An Observational Study	580	(1)
Birdkeeping and Lung Cancer--A Retrospective Observational Study	580	(3)
The Logistic Regression Model	583	(4)
Logistic Regression as a Generalized Linear Model	584	(1)
Interpretation of Coefficients	585	(2)
Estimation of Logistic Regression Coefficients	587	(5)
Maximum Likelihood Parameter Estimation	587	(3)
Tests and Confidence Intervals for Single Coefficients	590	(2)
The Drop-In-Deviance Test	592	(3)
Strategies for Data Analysis Using Logistic Regression	595	(1)
Exploratory Analysis	595	(1)
Analyses of Case Studies	596	(4)
Analysis of Donner Party Data	596	(1)
Analysis of Birdkeeping and Lung Cancer Data	597	(3)
Related Issues	600	(1)
Matched Case-Control Studies	600	(1)
Probit Regression	600	(1)
Discriminant Analysis Using Logistic Regression	601	(1)
Summary	601	(1)
Exercises	602	(7)
Conceptual Exercises	602	(1)
Computational Exercises	603	(2)
Data Problems	605	(3)
Answers to Conceptual Exercises	608	(1)
Logistic Regression for Binomial Counts	609	(35)
Case Studies	610	(4)
Island Size and Bird Extinctions--An Observational Study	610	(2)
Moth Coloration and Natural Selection--A Randomized Experiment	612	(2)
Logistic Regression for Binomial Responses	614	(1)
Binomial Responses	614	(1)
The Logistic Regression Model for Binomial Responses	614	(1)
Model Assessment	615	(3)
Scatterplot of Empirical Logits Versus an Explanatory Variable	615	(1)
Examination of Residuals	615	(1)
The Deviance Goodness-of-Fit Test	616	(2)
Inferences about Logistic Regression Coefficients	618	(3)
Wald's Tests and Confidence Intervals for Single Coefficients	618	(2)
The Drop-In-Deviance Test	620	(1)
Extra-Binomial Variation	621	(3)
Extra-Binomial Variation and the Logistic Regression Model	621	(1)
Checking for Extra-Binomial Variation	621	(1)
Quasi-Likelihood Inference When Extra-Binomial Variation Is Present	622	(2)
Analysis of Moth Predation Data	624	(3)
Related Issues	627	(9)
Why the Deviance Changes When Binary Observations Are Grouped	627	(1)
Logistic Models for Multilevel Categorical Responses	628	(2)
The Maximum Likelihood Principle	630	(3)
Bayesian Inference	633	(3)
Summary	636	(1)
Exercises	637	(7)
Conceptual Exercises	637	(1)
Computational Exercises	638	(2)
Data Problems	640	(2)
Answers to Conceptual Exercises	642	(2)
Log-Linear Regression for Poisson Counts	644	(25)
Case Studies	645	(3)
Age and Mating Success of Male Elephants--An Observational Study	645	(1)
Characteristics Associated with Salamander Habitat	646	(2)
Log-Linear Regression for Poisson Responses	648	(3)
Poisson Responses	648	(1)
The Poisson Log-Linear Model	649	(1)
Estimation by Maximum Likelihood	650	(1)
Model Assessment	651	(3)
Scatterplot of Logged Counts Versus an Explanatory Variable	651	(1)
Residuals	651	(1)
The Deviance Goodness-of-Fit Test	652	(2)
The Pearson Chi-Squared Goodness-of Fit Test	654	(1)
Inferences about Log-Linear Regression Coefficients	654	(2)
Wald's Test and Confidence Interval for Single Coefficients	654	(1)
The Drop-In-Deviance Test	655	(1)
Extra-Poisson Variation and the Log-Linear Model	656	(4)
Extra-Poisson Variation	656	(1)
Checking for Extra-Poisson Variation	656	(1)
Inferences When Extra-Poisson Variation Is Present	657	(3)
Related Issues	660	(2)
Log-Linear Models for Testing Independence in Tables of Counts	660	(1)
Poisson Counts from Varying Effort	661	(1)
Summary	662	(1)
Exercises	663	(6)
Conceptual Exercises	663	(1)
Computational Exercises	664	(1)
Data Problems	665	(3)
Answers to Conceptual Exercises	668	(1)
Elements of Research Design	669	(24)
Case Study	670	(1)
Biological Control of a Noxious Weed--A Randomized Experiment	670	(1)
Considerations in Forming Research Objectives	670	(1)
Research Design Tool Kit	671	(3)
Controls and Placebos	671	(1)
Blinding	672	(1)
Blocking	672	(1)
Stratification	672	(1)
Covariates	672	(1)
Randomization	673	(1)
Random Sampling	673	(1)
Replication	673	(1)
Balance	674	(1)
Design Choices that Affect Accuracy and Precision	674	(4)
Attaching Desired Precision to Practical Significance	674	(1)
How to Improve a Confidence Interval	675	(3)
Choosing a Sample Size	678	(2)
Studies with a Numerical Response	678	(1)
Studies Comparing Two Proportions	679	(1)
Sample Size for Estimating a Regression Coefficient	679	(1)
Steps in Designing a Study	680	(7)
Stating the Objective	680	(1)
Determining the Scope of Inference	681	(1)
Understanding the System	682	(1)
Deciding How to Measure a Response	682	(1)
Listing Factors that Can Affect the Response	683	(1)
Planning the Conduct of the Experiment	684	(1)
Outlining the Statistical Analysis	684	(1)
Determining the Sample Size	685	(2)
Related Issue--A Factor of Four	687	(1)
Summary	688	(1)
Exercises	689	(4)
Conceptual Exercises	689	(1)
Study Designs for Discussion	689	(1)
Computational Exercises	690	(1)
Design Problems	691	(1)
Answers to Conceptual Exercises	692	(1)
Factorial Treatment Arrangements and Blocking Designs	693	(22)
Case Study	694	(1)
Amphibian Crisis Linked to Ultraviolet Light-A Randomized Experiment	694	(1)
Treatments	695	(2)
Choosing Treatment Levels	695	(1)
The Rationale for Several Factors	696	(1)
Factorial Arrangement of Treatment Levels	697	(9)
Definition and Terminology for a Factorial Arrangement	697	(1)
The 22 Factorial Structure	697	(3)
The 23 Factorial Structure	700	(1)
The 32 Factorial Structure	701	(3)
Higher Order Factorial Arrangements	704	(2)
Blocking	706	(4)
Randomized Blocks	706	(2)
Latin Square Blocking	708	(1)
Split Plot Designs	709	(1)
Summary	710	(1)
Exercises	711	(4)
Conceptual Exercises	711	(2)
Computational Exercises	713	(1)
Data Problems	713	(1)
Answers to Conceptual Exercises	713	(2)
APPENDIX A Tables	715	(17)
A.1 Probabilities of the Standard Normal Distribution	716	(2)
A.2 Selected Percentiles of t-Distributions	718	(1)
A.3 Selected Percentiles of Chi-Squared Distributions	719	(1)
A.4 Selected Percentiles of F-Distributions	720	(8)
A.5 Selected Percentiles of Studentized Range Distributions	728	(4)
APPENDIX B Bibliography	732	(2)
Index	734