Elementary Statistics

785 Pages·2007·16.009 MB·English

by  Neil A. Weiss

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Elementary Statistics
Seventh Edition
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Elementary Statistics
Seventh Edition
Neil A. Weiss
Department of Mathematics and Statistics
Arizona State University
Biographies by Carol A. Weiss
San Francisco Boston New York
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Tomyfather
andthememory
ofmymother
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About the Author
NeilA.WeissreceivedhisPh.D.fromUCLAin1970andsubsequentlyaccepted
anassistant-professorpositionatArizonaStateUniversity(ASU),wherehewas
ultimatelypromotedtotherankoffullprofessor. Dr.Weisshastaughtstatis-
tics, probability, and mathematics—from the freshman level to the advanced
graduate level—for more than 30 years. In recognition of his excellence in
teaching,hereceivedtheDean’sQualityTeachingAwardfromtheASUCollege
ofLiberalArtsandSciences. Dr.Weiss’comprehensiveknowledgeandexperi-
enceensuresthathistextsaremathematicallyandstatisticallyaccurate,aswell
aspedagogicallysound.
Inadditiontohisnumerousresearchpublications,Dr.Weissistheauthorof
ACourseinProbability(Addison-Wesley,2006). Hehasalsoauthoredorcoau-
thoredbooksinfinitemathematics,statistics,andrealanalysis,andiscurrently
workingonanewbookonappliedregressionanalysisandtheanalysisofvari-
ance. His texts—well known for their precision, readability, and pedagogical
excellence—areusedworldwide.
Dr.Weissisapioneeroftheintegrationofstatisticalsoftwareintotextbooks
and the classroom, first providing such integration over 20 years ago in the
bookIntroductoryStatistics(Addison-Wesley,1982). WeissandAddison-Wesley
continuethatpioneeringspirittothisdaywiththeinclusionofsomeofthemost
comprehensiveWebsitesinthefield.
Inhissparetime,Dr.Weissenjoyswalking,studyingandpracticingmed-
itation,andplayinghold’empoker. Heismarriedandhastwosons.
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Contents
Preface xi
Supplements xxii
Technology Resources xxiii
Data Sources xxiv
Part I Introduction 1
Chapter 1 The Nature of Statistics 2
CaseStudy: GreatestAmericanScreenLegends 3
1.1 StatisticsBasics 4
1.2 SimpleRandomSampling 12
1.3 OtherSamplingDesigns* 18
1.4 ExperimentalDesigns* 24
ChapterinReview30,ReviewProblems31,FocusingonDataAnalysis34,
CaseStudyDiscussion34,Biography35
Part II Descriptive Statistics 37
Chapter 2 Organizing Data 38
CaseStudy: PreventingInfantMortality 39
2.1 VariablesandData 40
2.2 GroupingData 44
2.3 GraphsandCharts 56
2.4 DistributionShapes 72
2.5 MisleadingGraphs 81
ChapterinReview85,ReviewProblems86,FocusingonDataAnalysis90,
CaseStudyDiscussion90,Biography91
Chapter 3 Descriptive Measures 92
CaseStudy: TheTripleCrown 93
3.1 MeasuresofCenter 94
3.2 MeasuresofVariation 106
3.3 TheFive-NumberSummary;Boxplots 122
3.4 DescriptiveMeasuresforPopulations;UseofSamples 136
ChapterinReview148,ReviewProblems149,FocusingonDataAnalysis152,
CaseStudyDiscussion152,Biography153
vii
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viii Contents
Chapter 4 Descriptive Methods in Regression
and Correlation 154
CaseStudy: ShoeSizeandHeight 155
4.1 LinearEquationswithOneIndependentVariable 156
4.2 TheRegressionEquation 161
4.3 TheCoefficientofDetermination 177
4.4 LinearCorrelation 186
ChapterinReview196,ReviewProblems197,FocusingonDataAnalysis199,
CaseStudyDiscussion199,Biography200
Part III Probability, Random Variables, and Sampling Distributions 201
Chapter 5 Probability and Random Variables 202
CaseStudy: ThePowerball 203
5.1 ProbabilityBasics 204
5.2 Events 212
5.3 SomeRulesofProbability 221
5.4 DiscreteRandomVariablesandProbabilityDistributions* 229
5.5 TheMeanandStandardDeviationofaDiscreteRandomVariable* 237
5.6 TheBinomialDistribution* 243
ChapterinReview260,ReviewProblems260,FocusingonDataAnalysis263,
CaseStudyDiscussion264,Biography265
Chapter 6 The Normal Distribution 266
CaseStudy: FootLengthandShoeSizeforWomen 267
6.1 IntroducingNormallyDistributedVariables 268
6.2 AreasUndertheStandardNormalCurve 276
6.3 WorkingwithNormallyDistributedVariables 284
6.4 AssessingNormality;NormalProbabilityPlots 294
ChapterinReview301,ReviewProblems301,FocusingonDataAnalysis304,
CaseStudyDiscussion304,Biography305
Chapter 7 The Sampling Distribution of the Sample Mean 306
CaseStudy: TheChesapeakeandOhioFreightStudy 307
7.1 SamplingError;theNeedforSamplingDistributions 308
7.2 TheMeanandStandardDeviationoftheSampleMean 314
7.3 TheSamplingDistributionoftheSampleMean 321
ChapterinReview330,ReviewProblems330,FocusingonDataAnalysis333,
CaseStudyDiscussion333,Biography333
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Contents ix
Part IV Inferential Statistics 335
Chapter 8 Confidence Intervals for One Population Mean 336
CaseStudy: TheChipsAhoy! 1,000ChipsChallenge 337
8.1 EstimatingaPopulationMean 338
8.2 ConfidenceIntervalsforOnePopulationMeanWhenσ IsKnown 344
8.3 MarginofError 353
8.4 ConfidenceIntervalsforOnePopulationMeanWhenσ IsUnknown 359
ChapterinReview372,ReviewProblems372,FocusingonDataAnalysis376,
CaseStudyDiscussion376,Biography377
Chapter 9 Hypothesis Tests for One Population Mean 378
CaseStudy: SexandSenseofDirection 379
9.1 TheNatureofHypothesisTesting 380
9.2 Terms,Errors,andHypotheses 387
9.3 HypothesisTestsforOnePopulationMeanWhenσ IsKnown 396
9.4 P-Values 408
9.5 HypothesisTestsforOnePopulationMeanWhenσ IsUnknown 420
ChapterinReview432,ReviewProblems432,FocusingonDataAnalysis438,
CaseStudyDiscussion438,Biography439
Chapter 10 Inferences for Two Population Means 440
CaseStudy: BreastMilkandIQ 441
10.1 TheSamplingDistributionoftheDifferenceBetweenTwoSampleMeansfor
IndependentSamples 442
10.2 InferencesforTwoPopulationMeans,UsingIndependentSamples: Standard
DeviationsAssumedEqual 448
10.3 InferencesforTwoPopulationMeans,UsingIndependentSamples: Standard
DeviationsNotAssumedEqual 462
10.4 InferencesforTwoPopulationMeans,UsingPairedSamples 477
ChapterinReview493,ReviewProblems493,FocusingonDataAnalysis498,
CaseStudyDiscussion498,Biography499
Chapter 11 Inferences for Population Proportions 500
CaseStudy: WorldWarIII? 501
11.1 ConfidenceIntervalsforOnePopulationProportion 502
11.2 HypothesisTestsforOnePopulationProportion 514
11.3 InferencesforTwoPopulationProportions 521
ChapterinReview535,ReviewProblems535,FocusingonDataAnalysis538,
CaseStudyDiscussion538,Biography538
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x Contents
Chapter 12 Chi-Square Procedures 540
CaseStudy: RoadRage 541
12.1 TheChi-SquareDistribution 542
12.2 Chi-SquareGoodness-of-FitTest 543
12.3 ContingencyTables;Association 554
12.4 Chi-SquareIndependenceTest 566
ChapterinReview579,ReviewProblems579,FocusingonDataAnalysis582,
CaseStudyDiscussion582,Biography583
Chapter 13 Analysis of Variance (ANOVA) 584
CaseStudy: HeavyDrinkingAmongCollegeStudents 585
13.1 TheF-Distribution 586
13.2 One-WayANOVA:TheLogic 587
13.3 One-WayANOVA:TheProcedure 595
ChapterinReview610,ReviewProblems610,FocusingonDataAnalysis612,
CaseStudyDiscussion612,Biography613
Chapter 14 Inferential Methods in Regression
and Correlation 614
CaseStudy: ShoeSizeandHeight 615
14.1 TheRegressionModel;AnalysisofResiduals 616
14.2 InferencesfortheSlopeofthePopulationRegressionLine 629
14.3 EstimationandPrediction 637
14.4 InferencesinCorrelation 647
ChapterinReview654,ReviewProblems655,FocusingonDataAnalysis658,
CaseStudyDiscussion658,Biography659
Appendixes
Appendix A Statistical Tables A-1
Appendix B Answers to Selected Exercises A-27
Index I-1
Photo Credits C-1
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