Richard De Veaux, Paul Velleman, and David Bock wrote Intro Statswith the goal that you have as much fun reading it as they did in writing it. Maintaining a conversational, humorous, and informal writing style, this new edition engages readers from the first page. The authors focus on statistical thinking throughout the text and rely on technology for calculations. As a result, students can focus on developing their conceptual understanding. Innovative Think/Show/Tell examples provide a problem-solving framework and, more importantly, a way to think through any statistics problem and present their results. New to the Fourth Editionis a streamlined presentation that keeps students focused on what's most important, while including out helpful features. An updated organization divides chapters into sections, with specific learning objectives to keep students on track. A detailed table of contents assists with navigation through this new layout. Single-concept exercises complement the existing mid- to hard-level exercises for basic skill development.

Preface

Index of Applications

**Part I. Exploring and Understanding Data**

**1. Stats Starts Here!**

1.1 What Is Statistics?

1.2 Data

1.3 Variables

**2. Displaying and Describing Categorical Data **

2.1 Summarizing and Displaying a Single Categorical Variable

2.2 Exploring the Relationship Between Two Categorical Variables

**3. Displaying and Summarizing Quantitative Data**

3.1 Displaying Quantitative Variables

3.2 Shape

3.3 Center

3.4 Spread

3.5 Boxplots and 5-Number Summaries

3.6 The Center of Symmetric Distributions: The Mean

3.7 The Spread of Symmetric Distributions: The Standard Deviation

3.8 Summary—What to *Tell* About a Quantitative Variable

**4. Understanding and Comparing Distributions**

4.1 Comparing Groups with Histograms

4.2 Comparing Groups with Boxplots

4.3 Outliers

4.4 Timeplots: Order, Please!

4.5 Re-expressing Data: A First Look

**5. The Standard Deviation as a Ruler and the Normal Model**

5.1 Standardizing with *z*-Scores

5.2 Shifting and Scaling

5.3 Normal Models

5.4 Finding Normal Percentiles

5.5 Normal Probability Plots

Review of Part I. Exploring and Understanding Data

**Part II. Exploring Relationships Between Variables**

**6. Scatterplots, Association, and Correlation**

6.1 Scatterplots

6.2 Correlation

6.3 Warning: Correlation ≠ Causation

6.4 Straightening Scatterplots

**7. Linear Regression**

7.1 Least Squares: The Line of "Best Fit"

7.2 The Linear Model

7.3 Finding the Least Squares Line

7.4 Regression to the Mean

7.5 Examining the Residuals

7.6 R2—The Variation Accounted for by the Model

7.7 Regression Assumptions and Conditions

**8. Regression Wisdom**

8.1 Examining Residuals

8.2 Extrapolation: Reaching Beyond the Data

8.3 Outliers, Leverage, and Influence

8.4 Lurking Variables and Causation

8.5 Working with Summary Values

Review of Part II. Exploring Relationships Between Variables

**Part III. Gathering Data**

**9. Understanding Randomness**

9.1 What is Randomness?

9.2 Simulating By Hand

**10. Sample Surveys**

10.1 The Three Big Ideas of Sampling

10.2 Populations and Parameters

10.3 Simple Random Samples

10.4 Other Sampling Designs

10.5 From the Population to the Sample: You Can't Always Get What You Want

10.6 The Valid Survey

10.7 Common Sampling Mistakes, or How to Sample Badly

**11. Experiments and Observational Studies**

11.1 Observational Studies

11.2 Randomized, Comparative Experiments

11.3 The Four Principles of Experimental Design

11.4 Control Treatments

11.5 Blocking

11.6 Confounding

Review of Part III. Gathering Data

**Part IV. Randomness and Probability**

**12. From Randomness to Probability**

12.1 Random Phenomena

12.2 Modeling Probability

12.3 Formal Probability

**13. Probability Rules!**

13.1 The General Addition Rule

13.2 Conditional Probability and the General Multiplication Rule

13.3 Independence

13.4 Picturing Probability: Tables, Venn Diagrams and Trees

13.5 Reversing the Conditioning and Bayes' Rule

**14. Random Variables and Probability Models**

14.1 Expected Value: Center

14.2 Standard Deviation

14.3 Combining Random Variables

14.4 The Binomial Model

14.5 Modeling the Binomial with a Normal Model

*14.6 The Poisson Model

14.7 Continuous Random Variables

Review of Part IV Randomness and Probability

**Part V. From the Data at Hand to the World at Large**

**15. Sampling Distribution Models**

15.1 Sampling Distribution of a Proportion

15.2 When Does the Normal Model Work? Assumptions and Conditions

15.3 The Sampling Distribution of Other Statistics

15.4 The Central Limit Theorem: The Fundamental Theorem of Statistics

15.5 Sampling Distributions: A Summary

**16. Confidence Intervals for Proportions**

16.1 A Confidence Interval

16.2 Interpreting Confidence Intervals: What Does 95% Confidence Really Mean?

16.3 Margin of Error: Certainty vs. Precision

16.4 Assumptions and Conditions

**17. Testing Hypotheses About Proportions**

17.1 Hypotheses

17.2 *P*-Values

17.3 The Reasoning of Hypothesis Testing

17.4 Alternative Alternatives

17.5 *P*-Values and Decisions: What to Tell About a Hypothesis Test

**18. Inferences About Means**

18.1: Getting Started: The Central Limit Theorem (Again)

18.2: Gosset's t

18.3 Interpreting Confidence Intervals

18.4 A Hypothesis Test for the Mean

18.5 Choosing the Sample Size

**19. More About Tests and Intervals**

19.1 Choosing Hypotheses

19.2 How to Think About P Values

19.3 Alpha Levels

19.4 Practical vs. Statistical Significance

19.5 Critical Values Again

19.6 Errors

19.7 Power

Review of Part V From the Data at Hand to the World at Large

**Part VI. Learning About the World**

**20. Comparing Groups**

20.1 The Variance of a Difference

20.2 The Standard Deviation of the Difference Between Two Proportions

20.3 Assumptions and Conditions for Comparing Proportions

20.4 The Sampling Distribution of the Difference between Two Proportions

20.5 Comparing Two Means

20.6 The Two-Sample t-Test: Testing for the Difference Between Two Means

20.7 The Two Sample z-Test: Testing for the Difference between Proportions

20.8 The Pooled t-Test: Everyone into the Pool?

20.9 Pooling

**21. Paired Samples and Blocks**

21.1 Paired Data

21.2 Assumptions and Conditions

21.3 Confidence Intervals for Matched Pairs

21.4 Blocking

**22. Comparing Counts**

22.1 Goodness-of-Fit Tests

22.2 Chi-Square Test of Homogeneity

22.3 Examining the Residuals

22.4 Chi-Square Test of Independence

**23. Inferences for Regression**

23.1 The Population and the Sample

23.2 Assumptions and Conditions

23.3 Intuition About Regression Inference

23.4 Regression Inference

23.5 Standard Errors for Predicted Values

23.6 Confidence Intervals for

Predicted Values

*23.7 Logistic Regression

Review of Part VI Learning About the World

**Part VII. Inference When Variables Are Related**

**24 Analysis of Variance**

24.1 Testing Whether the Means of Several Groups Are Equal

24.2 The ANOVA Table

24.3 Plot the Data…

24.4 Comparing Means

**25. Multiple Regression**

25.1 Two Predictors

25.2 What Multiple Regression Coefficients Mean

25.3 The Multiple Regression Model

25.4 Multiple Regression Inference

25.5 Comparing Multiple Regression Models

**Appendices**

A. Answers

B. Photo Acknowledgments

C. Index

D. Tables and Selected Formulas

*Indicates an optional section