统计学第七章.ppt

TheNormalProbabilityDistributionChapter7

GOALSUnderstandthedifferencebetweendiscreteandcontinuousdistributions.Computethemeanandthestandarddeviationforauniformdistribution.Computeprobabilitiesbyusingtheuniformdistribution.Listthecharacteristicsofthenormalprobabilitydistribution.Defineandcalculatezvalues.Determinetheprobabilityanobservationisbetweentwopointsonanormalprobabilitydistribution.Determinetheprobabilityanobservationisabove(orbelow)apointonanormalprobabilitydistribution.Usethenormalprobabilitydistributiontoapproximatethebinomialdistribution.2

TheUniformDistributionTheuniformprobabilitydistributionisperhapsthesimplestdistributionforacontinuousrandomvariable.Thisdistributionisrectangularinshapeandisdefinedbyminimumandmaximumvalues.3

TheUniformDistribution–MeanandStandardDeviation4

SouthwestArizonaStateUniversityprovidesbusservicetostudentswhiletheyareoncampus.AbusarrivesattheNorthMainStreetandCollegeDrivestopevery30minutesbetween6A.M.and11P.M.duringweekdays.Studentsarriveatthebusstopatrandomtimes.Thetimethatastudentwaitsisuniformlydistributedfrom0to30minutes.1.Drawagraphofthisdistribution.2.Howlongwillastudent“typically”havetowaitforabus?Inotherwordswhatisthemeanwaitingtime?Whatisthestandarddeviationofthewaitingtimes?3.Whatistheprobabilityastudentwillwaitmorethan25minutes?4.Whatistheprobabilityastudentwillwaitbetween10and20minutes?TheUniformDistribution-Example5

TheUniformDistribution-ExampleDrawagraphofthisdistribution.6

TheUniformDistribution-ExampleHowlongwillastudent“typically”havetowaitforabus?Inotherwordswhatisthemeanwaitingtime?Whatisthestandarddeviationofthewaitingtimes?7

TheUniformDistribution-ExampleWhatistheprobabilityastudentwillwaitmorethan25minutes?8

TheUnif