Table Of ContentIntroductory
STATISTICS
10TH EDITION
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Introductory
STATISTICS
10TH EDITION
Neil A. Weiss, Ph.D.
School of Mathematical and Statistical Sciences
Arizona State University
Biographies by Carol A. Weiss
Boston Columbus Indianapolis New York San Francisco
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Weiss,N.A.(NeilA.)
Introductorystatistics/NeilA.Weiss,ArizonaStateUniversity;biographiesbyCarolA.Weiss.–10thedition.
pagescm
Includesindex.
ISBN978-0-321-98917-8
1. Statistics–Textbooks. I. Weiss,CarolA. II. Title.
QA276.12.W452016
519.5–dc23
2014019105
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ISBN13:978-0-321-98917-8
ISBN10:0-321-98917-1
About the Author
NeilA.WeissreceivedhisPh.D.fromUCLAandsubsequentlyacceptedanassistant
professor position at Arizona State University (ASU), where he was ultimately pro-
moted to the rank of full professor. Dr. Weiss has taught statistics, probability, and
mathematics—fromthefreshmanleveltotheadvancedgraduatelevel—formorethan
30years.
Inrecognitionofhisexcellenceinteaching,Dr.WeissreceivedtheDean’sQuality
Teaching Award from the ASU College of Liberal Arts and Sciences. He has also
been runner-up twice for the Charles Wexler Teaching Award in the ASU School
of Mathematical and Statistical Sciences. Dr. Weiss’s comprehensive knowledge and
experienceensuresthathistextsaremathematicallyandstatisticallyaccurate,aswell
aspedagogicallysound.
In addition to his numerous research publications, Dr. Weiss is the author of A
Course in Probability (Addison-Wesley, 2006). He has also authored or coauthored
books in finite mathematics, statistics, and real analysis, and is currently working on
a new book on applied regression analysis and the analysis of variance. His texts—
well known for their precision, readability, and pedagogical excellence—are used
worldwide.
Dr.Weissisapioneeroftheintegrationofstatisticalsoftwareintotextbooksandthe
classroom,firstprovidingsuchintegrationinthebookIntroductoryStatistics(Addison-
Wesley,1982).HeandPearsonEducationcontinuethatspirittothisday.
In his spare time, Dr. Weiss enjoys walking, studying and practicing meditation,
andplayinghold’empoker.Heismarriedandhastwosons.
Dedicated to Aaron and Greg
v
Contents
Preface xi
Supplements xvi
TechnologyResources xvii
DataSources xix
PART I Introduction
CHAPTER 1 The Nature of Statistics
1
CaseStudy:TopFilmsofAllTime 1
• •
1.1StatisticsBasics 2 1.2SimpleRandomSampling 9 1.3Other
SamplingDesigns∗ 17 • 1.4ExperimentalDesigns∗ 25
• • •
ChapterinReview31 ReviewProblems31 FocusingonDataAnalysis34
•
CaseStudyDiscussion34 Biography34
PART II Descriptive Statistics
CHAPTER 2 Organizing Data
36
CaseStudy:World’sRichestPeople 36
• •
2.1VariablesandData 37 2.2OrganizingQualitativeData 42
• •
2.3OrganizingQuantitativeData 52 2.4DistributionShapes 75
2.5MisleadingGraphs∗ 83
• • •
ChapterinReview87 ReviewProblems88 FocusingonDataAnalysis91
•
CaseStudyDiscussion91 Biography92
CHAPTER 3 Descriptive Measures
93
CaseStudy:TheBeatles’SongLength 93
• •
3.1MeasuresofCenter 94 3.2MeasuresofVariation 105
3.3Chebyshev’sRuleandtheEmpiricalRule∗ 117 • 3.4TheFive-Number
•
Summary;Boxplots 125 3.5DescriptiveMeasuresforPopulations;Useof
Samples 139
• •
ChapterinReview150 ReviewProblems150 FocusingonData
• •
Analysis153 CaseStudyDiscussion154 Biography154
∗Indicatesoptionalmaterial.
vi
CONTENTS vii
PART III Probability, Random Variables,
and Sampling Distributions
CHAPTER 4 Probability Concepts
156
CaseStudy:TexasHold’em 156
• •
4.1ProbabilityBasics 157 4.2Events 164 4.3SomeRulesof
•
Probability 173 4.4ContingencyTables;JointandMarginal
Probabilities∗ 179 • 4.5ConditionalProbability∗ 185 • 4.6The
MultiplicationRule;Independence∗ 193 • 4.7Bayes’sRule∗ 201 •
4.8CountingRules∗ 208
• •
ChapterinReview218 ReviewProblems218 FocusingonData
• •
Analysis221 CaseStudyDiscussion222 Biography222
∗
CHAPTER 5 Discrete Random Variables
223
CaseStudy:AcesWildontheSixthatOakHill 223
5.1DiscreteRandomVariablesandProbabilityDistributions∗ 224 • 5.2The
MeanandStandardDeviationofaDiscreteRandomVariable∗ 231 • 5.3The
BinomialDistribution∗ 238 • 5.4ThePoissonDistribution∗ 251
• •
ChapterinReview258 ReviewProblems259 FocusingonData
• •
Analysis261 CaseStudyDiscussion261 Biography261
CHAPTER 6 The Normal Distribution
262
CaseStudy:ChestSizesofScottishMilitiamen 262
•
6.1IntroducingNormallyDistributedVariables 263 6.2Areasunderthe
•
StandardNormalCurve 274 6.3WorkingwithNormallyDistributed
• •
Variables 280 6.4AssessingNormality;NormalProbabilityPlots 290
6.5NormalApproximationtotheBinomialDistribution∗ 296
• •
ChapterinReview303 ReviewProblems304 FocusingonData
• •
Analysis306 CaseStudyDiscussion306 Biography306
CHAPTER 7 The Sampling Distribution of the Sample Mean
307
CaseStudy:TheChesapeakeandOhioFreightStudy 307
•
7.1SamplingError;theNeedforSamplingDistributions 308 7.2TheMean
•
andStandardDeviationoftheSampleMean 313 7.3TheSampling
DistributionoftheSampleMean 319
• •
ChapterinReview326 ReviewProblems327 FocusingonData
• •
Analysis329 CaseStudyDiscussion329 Biography329
PART IV Inferential Statistics
CHAPTER 8 Confidence Intervals for One Population Mean
331
CaseStudy:BankRobberies:AStatisticalAnalysis 331
•
8.1EstimatingaPopulationMean 332 8.2ConfidenceIntervalsforOne
PopulationMeanWhenσ IsKnown 338 • 8.3ConfidenceIntervalsforOne
PopulationMeanWhenσ IsUnknown 352
• •
ChapterinReview363 ReviewProblems363 FocusingonData
• •
Analysis366 CaseStudyDiscussion366 Biography366
∗Indicatesoptionalmaterial.
viii CONTENTS
CHAPTER 9 Hypothesis Tests for One Population Mean
367
CaseStudy:GenderandSenseofDirection 367
•
9.1TheNatureofHypothesisTesting 368 9.2Critical-ValueApproachto
HypothesisTesting 376 • 9.3P-ValueApproachtoHypothesisTesting 381 •
9.4HypothesisTestsforOnePopulationMeanWhenσ IsKnown 387 •
9.5HypothesisTestsforOnePopulationMeanWhenσ IsUnknown 399 •
9.6TheWilcoxonSigned-RankTest∗ 407 • 9.7TypeIIErrorProbabilities;
Power∗ 422 • 9.8WhichProcedureShouldBeUsed?∗∗
• •
ChapterinReview433 ReviewProblems433 FocusingonData
• •
Analysis437 CaseStudyDiscussion437 Biography437
CHAPTER 10 Inferences for Two Population Means
438
CaseStudy:DexamethasoneTherapyandIQ 438
10.1TheSamplingDistributionoftheDifferencebetweenTwoSampleMeansfor
•
IndependentSamples 439 10.2InferencesforTwoPopulationMeans,Using
•
IndependentSamples:StandardDeviationsAssumedEqual 446
10.3InferencesforTwoPopulationMeans,UsingIndependentSamples:
•
StandardDeviationsNotAssumedEqual 458 10.4TheMann–Whitney
Test∗ 470 • 10.5InferencesforTwoPopulationMeans,UsingPaired
Samples 485 • 10.6ThePairedWilcoxonSigned-RankTest∗ 498 •
10.7WhichProcedureShouldBeUsed?∗∗
• •
ChapterinReview508 ReviewProblems509 FocusingonData
• •
Analysis511 CaseStudyDiscussion511 Biography511
∗
CHAPTER 11 Inferences for Population Standard Deviations
513
CaseStudy:SpeakerWooferDriverManufacturing 513
11.1InferencesforOnePopulationStandardDeviation∗ 514 • 11.2Inferences
forTwoPopulationStandardDeviations,UsingIndependentSamples∗ 527
• •
ChapterinReview541 ReviewProblems541 FocusingonData
• •
Analysis543 CaseStudyDiscussion543 Biography543
CHAPTER 12 Inferences for Population Proportions
544
CaseStudy:ArrestedYouths 544
•
12.1ConfidenceIntervalsforOnePopulationProportion 545
•
12.2HypothesisTestsforOnePopulationProportion 557 12.3Inferences
forTwoPopulationProportions 561
• •
ChapterinReview573 ReviewProblems573 FocusingonData
• •
Analysis575 CaseStudyDiscussion575 Biography575
CHAPTER 13 Chi-Square Procedures
576
CaseStudy:EyeandHairColor 576
•
13.1TheChi-SquareDistribution 577 13.2Chi-SquareGoodness-of-Fit
• •
Test 578 13.3ContingencyTables;Association 587 13.4Chi-Square
•
IndependenceTest 597 13.5Chi-SquareHomogeneityTest 606
• •
ChapterinReview613 ReviewProblems614 FocusingonData
• •
Analysis617 CaseStudyDiscussion617 Biography617
∗Indicatesoptionalmaterial.
∗∗IndicatesoptionalmaterialontheWeissStatssite.
CONTENTS ix
PART V Regression, Correlation, and ANOVA
CHAPTER 14 Descriptive Methods in Regression and Correlation
618
CaseStudy:Healthcare:SpendingandOutcomes 618
•
14.1LinearEquationswithOneIndependentVariable 619 14.2The
• •
RegressionEquation 624 14.3TheCoefficientofDetermination 638
14.4LinearCorrelation 645
• •
ChapterinReview653 ReviewProblems654 FocusingonData
• •
Analysis655 CaseStudyDiscussion656 Biography656
CHAPTER 15 Inferential Methods in Regression and Correlation
657
CaseStudy:ShoeSizeandHeight 657
•
15.1TheRegressionModel;AnalysisofResiduals 658 15.2Inferencesfor
•
theSlopeofthePopulationRegressionLine 670 15.3Estimationand
• •
Prediction 678 15.4InferencesinCorrelation 688 15.5Testingfor
Normality∗∗
• •
ChapterinReview694 ReviewProblems694 FocusingonData
• •
Analysis696 CaseStudyDiscussion696 Biography697
CHAPTER 16 Analysis of Variance (ANOVA)
698
CaseStudy:Self-PerceptionandPhysicalActivity 698
16.1TheF-Distribution 699 • 16.2One-WayANOVA:TheLogic 701 •
•
16.3One-WayANOVA:TheProcedure 707 16.4Multiple
Comparisons∗ 720 • 16.5TheKruskal–WallisTest∗ 728
• •
ChapterinReview738 ReviewProblems738 FocusingonData
• •
Analysis740 CaseStudyDiscussion741 Biography741
PART VI Multiple Regression and Model Building;
∗∗
Experimental Design and ANOVA
MODULE A Multiple Regression Analysis
A-0
CaseStudy:AutomobileInsuranceRates A-0
•
A.1TheMultipleLinearRegressionModel A-1 A.2Estimationofthe
•
RegressionParameters A-6 A.3InferencesConcerningtheUtilityofthe
•
RegressionModel A-21 A.4InferencesConcerningtheUtilityofParticular
•
PredictorVariables A-31 A.5ConfidenceIntervalsforMeanResponse;
•
PredictionIntervalsforResponse A-37 A.6CheckingModelAssumptions
andResidualAnalysis A-47
• •
ModuleinReviewA-59 ReviewProblemsA-59 FocusingonData
• •
AnalysisA-62 CaseStudyDiscussionA-63 AnswerstoSelected
•
ExercisesA-65 IndexA-68
MODULE B Model Building in Regression
B-0
CaseStudy:AutomobileInsuranceRates—Revisited B-0
•
B.1TransformationstoRemedyModelViolations B-1 B.2Polynomial
• •
RegressionModel B-32 B.3QualitativePredictorVariables B-64
∗Indicatesoptionalmaterial.
∗∗IndicatesoptionalmaterialontheWeissStatssite.
