Collaborative Statistics for MT230 Collection Editor: Robert Gallagher Collaborative Statistics for MT230 Collection Editor: Robert Gallagher Authors: Susan Dean Barbara Illowsky, Ph.D. Online: < http://cnx.org/content/col11345/1.2/ > C O N N E X I O N S Rice University, Houston, Texas ThisselectionandarrangementofcontentasacollectioniscopyrightedbyRobertGallagher. Itislicensedunderthe CreativeCommonsAttribution3.0license(http://creativecommons.org/licenses/by/3.0/). Collectionstructurerevised:August18,2011 PDFgenerated:June20,2012 Forcopyrightandattributioninformationforthemodulescontainedinthiscollection,seep.593. Table of Contents Preface ................................................................................................1 AdditionalResources .............................................................. ...................5 AuthorAcknowledgements ....................................................... ...................9 StudentWelcomeLetter ..............................................................................11 1 SamplingandData 1.1 SamplingandData ..........................................................................13 1.2 Statistics ....................................................................................13 1.3 Probability ..................................................................................15 1.4 KeyTerms ..................................................................................15 1.5 Data ........................................................................................17 1.6 Variation ....................................................................................18 1.7 AnswersandRoundingOff .................................................................20 1.8 Frequency ..................................................................... .............21 1.9 Summary ...................................................................................25 1.10 Practice: SamplingandData ...............................................................26 1.11 Homework ................................................................................29 1.12 Lab1: DataCollection ......................................................................37 1.13 Lab2: SamplingExperiment ...............................................................39 Solutions ........................................................................................42 2 DescriptiveStatistics 2.1 DescriptiveStatistics ........................................................................45 2.2 DisplayingData .............................................................................45 2.3 StemandLeafGraphs(Stemplots),LineGraphsandBarGraphs .............................46 2.4 Histograms .................................................................................49 2.5 MeasuresoftheCenteroftheData ..........................................................53 2.6 SkewnessandtheMean,Median,andMode .................................................56 2.7 MeasuresoftheSpreadoftheData ..........................................................58 2.8 SummaryofFormulas ......................................................... .............67 2.9 Practice1: CenteroftheData ................................................................68 2.10 Practice2: SpreadoftheData ..............................................................71 2.11 Homework ................................................................................72 2.12 Lab: DescriptiveStatistics ..................................................................89 Solutions ........................................................................................91 3 LinearRegressionandCorrelation 3.1 LinearRegressionandCorrelation ...........................................................97 3.2 LinearEquations ............................................................................97 3.3 SlopeandY-InterceptofaLinearEquation ..................................... .............99 3.4 ScatterPlots ................................................................................100 3.5 TheRegressionEquation ...................................................................102 3.6 CorrelationCoefficientandCoefficientofDetermination ...................................108 3.7 TestingtheSignificanceoftheCorrelationCoefficient .......................................110 3.8 Prediction ..................................................................................115 3.9 Outliers ....................................................................................115 3.10 95%CriticalValuesoftheSampleCorrelationCoefficientTable ............................122 3.11 Summary .................................................................................125 3.12 Practice: LinearRegression ................................................................126 iv 3.13 Homework ...............................................................................129 3.14 Lab1: Regression(DistancefromSchool) ..................................................144 3.15 Lab2: Regression(TextbookCost) .........................................................147 3.16 Lab3: Regression(FuelEfficiency) ........................................................149 Solutions .......................................................................................152 4 ProbabilityTopics 4.1 ProbabilityTopics ..........................................................................157 4.2 Terminology ...............................................................................158 4.3 IndependentandMutuallyExclusiveEvents ...............................................160 4.4 TwoBasicRulesofProbability ..............................................................163 4.5 ContingencyTables ........................................................................167 4.6 VennDiagrams(optional) ..................................................................170 4.7 TreeDiagrams(optional) ...................................................................171 4.8 SummaryofFormulas .....................................................................176 4.9 Practice1: ContingencyTables .............................................................177 4.10 Practice2: CalculatingProbabilities .......................................................179 4.11 Homework ...............................................................................180 4.12 Review ...................................................................................191 4.13 Lab: ProbabilityTopics ....................................................................193 Solutions .......................................................................................196 5 DiscreteRandomVariables 5.1 DiscreteRandomVariables .................................................................203 5.2 ProbabilityDistributionFunction(PDF)foraDiscreteRandomVariable ....................204 5.3 MeanorExpectedValueandStandardDeviation ...........................................205 5.4 CommonDiscreteProbabilityDistributionFunctions .......................................208 5.5 Binomial ...................................................................................208 5.6 SummaryofFunctions .....................................................................212 5.7 Practice1: DiscreteDistribution ............................................................214 5.8 Practice2: BinomialDistribution ...........................................................215 5.9 Homework ................................................................................217 5.10 Review ...................................................................................227 5.11 Lab1: DiscreteDistribution(PlayingCardExperiment) ...................................230 5.12 Lab2: DiscreteDistribution(LuckyDiceExperiment) .....................................234 Solutions .......................................................................................238 6 TheNormalDistribution 6.1 TheNormalDistribution ...................................................................245 6.2 TheStandardNormalDistribution .........................................................246 6.3 Z-scores ....................................................................................247 6.4 AreastotheLeftandRightofx .............................................................249 6.5 CalculationsofProbabilities ................................................................249 6.6 SummaryofFormulas .....................................................................253 6.7 Practice: TheNormalDistribution ..........................................................254 6.8 Homework ................................................................................256 6.9 Review ....................................................................................262 6.10 Lab1: NormalDistribution(LapTimes) ...................................................264 6.11 Lab2: NormalDistribution(PinkieLength) ...............................................267 Solutions .......................................................................................269 7 TheCentralLimitTheorem 7.1 TheCentralLimitTheorem .................................................................273 7.2 TheCentralLimitTheoremforSampleMeans(Averages) ...................................274 v 7.3 TheCentralLimitTheoremforSums .......................................................277 7.4 UsingtheCentralLimitTheorem ...........................................................278 7.5 SummaryofFormulas .....................................................................286 7.6 Practice: TheCentralLimitTheorem .......................................................287 7.7 Homework ................................................................................290 7.8 Review ....................................................................................297 7.9 Lab1: CentralLimitTheorem(PocketChange) .............................................299 7.10 Lab2: CentralLimitTheorem(CookieRecipes) ............................................303 Solutions .......................................................................................308 8 ConfidenceIntervals 8.1 ConfidenceIntervals .......................................................................311 8.2 Confidence Interval, Single Population Mean, Population Standard Deviation Known,Normal ...........................................................................313 8.3 Confidence Interval, Single Population Mean, Standard Deviation Unknown, Student-T ..................................................................................320 8.4 ConfidenceIntervalforaPopulationProportion ............................................323 8.5 SummaryofFormulas .....................................................................328 8.6 Practice1: ConfidenceIntervalsforAverages,KnownPopulationStandardDevi- ation ......................................................................................329 8.7 Practice2:ConfidenceIntervalsforAverages,UnknownPopulationStandardDe- viation .....................................................................................331 8.8 Practice3: ConfidenceIntervalsforProportions ............................................333 8.9 Homework ................................................................................335 8.10 Review ...................................................................................345 8.11 Lab1: ConfidenceInterval(HomeCosts) ..................................................348 8.12 Lab2: ConfidenceInterval(PlaceofBirth) .................................................351 8.13 Lab3: ConfidenceInterval(Womens’Heights) ............................................353 Solutions .......................................................................................355 9 HypothesisTesting: SingleMeanandSingleProportion 9.1 HypothesisTesting: SingleMeanandSingleProportion ....................................361 9.2 NullandAlternateHypotheses .............................................................362 9.3 OutcomesandtheTypeIandTypeIIErrors ................................................363 9.4 DistributionNeededforHypothesisTesting ................................................364 9.5 Assumption ................................................................................365 9.6 RareEvents ................................................................................365 9.7 UsingtheSampletoSupportOneoftheHypotheses .......................................366 9.8 DecisionandConclusion ...................................................................367 9.9 AdditionalInformation ....................................................................367 9.10 SummaryoftheHypothesisTest ..........................................................369 9.11 Examples .................................................................................369 9.12 SummaryofFormulas ....................................................................380 9.13 Practice1: SingleMean,KnownPopulationStandardDeviation ...........................381 9.14 Practice2: SingleMean,UnknownPopulationStandardDeviation ........................383 9.15 Practice3: SingleProportion ..............................................................385 9.16 Homework ...............................................................................387 9.17 Review ...................................................................................400 9.18 Lab: HypothesisTestingofaSingleMeanandSingleProportion ...........................403 Solutions .......................................................................................407 10 HypothesisTesting: TwoMeans,PairedData,TwoProportions 10.1 HypothesisTesting: TwoPopulationMeansandTwoPopulationProportions ..............413 vi 10.2 Comparing Two Independent Population Means with Unknown Population StandardDeviations .......................................................................414 10.3 ComparingTwoIndependentPopulationMeanswithKnownPopulationStan- dardDeviations ...........................................................................417 10.4 ComparingTwoIndependentPopulationProportions .....................................419 10.5 MatchedorPairedSamples ...............................................................421 10.6 SummaryofTypesofHypothesisTests ....................................................426 10.7 Practice1: HypothesisTestingforTwoProportions ........................................427 10.8 Practice2: HypothesisTestingforTwoAverages ..........................................429 10.9 Homework ...............................................................................431 10.10 Review ..................................................................................443 10.11 Lab: HypothesisTestingforTwoMeansandTwoProportions ............................445 Solutions .......................................................................................450 11 TheChi-SquareDistribution 11.1 TheChi-SquareDistribution ..............................................................455 11.2 Notation ..................................................................................456 11.3 FactsAbouttheChi-SquareDistribution ..................................................456 11.4 Goodness-of-FitTest ......................................................................458 11.5 TestofIndependence ......................................................................465 11.6 SummaryofFormulas ....................................................................470 11.7 Practice1: Goodness-of-FitTest ...........................................................471 11.8 Practice2: ContingencyTables ............................................................473 11.9 Homework ...............................................................................475 11.10 Review ..................................................................................484 11.11 Lab1: Chi-SquareGoodness-of-Fit .......................................................488 11.12 Lab2: Chi-SquareTestforIndependence .................................................493 Solutions .......................................................................................495 12 FDistributionandANOVA 12.1 FDistributionandANOVA ...............................................................501 12.2 ANOVA ..................................................................................502 12.3 TheFDistributionandtheFRatio .........................................................502 12.4 FactsAbouttheFDistribution ............................................................504 12.5 Summary .................................................................................509 12.6 Practice: ANOVA .........................................................................510 12.7 Homework ...............................................................................512 12.8 Review ...................................................................................514 12.9 Lab: ANOVA .............................................................................518 Solutions .......................................................................................520 13 Appendix 13.1 PracticeFinalExam1 .....................................................................523 13.2 PracticeFinalExam2 .....................................................................532 13.3 DataSets ..................................................................................541 13.4 GroupProjects ............................................................................544 13.5 SolutionSheets ...........................................................................555 13.6 EnglishPhrasesWrittenMathematically ...................................................559 13.7 SymbolsandtheirMeanings ..............................................................560 13.8 Formulas .................................................................................565 13.9 NotesfortheTI-83,83+,84Calculator .....................................................567 Solutions .......................................................................................577 14 Tables ............................................................................................581 vii Glossary .............................................................................................582 Index ................................................................................................589 Attributions .........................................................................................593 viii