基础统计学英文版

Chapter11ChapterOneWhatisStatistics?ONEUnderstandwhywestudystatistics.TWOExplainwhatismeantbydescriptivestatisticsandinferentialstatistics.THREEDistinguishbetweenaqualitativevariableandaquantitativevariable.FOUR

Distinguishbetweenadiscretevariableandacontinuousvariable.FIVEDistinguishamongthenominal,ordinal,interval,andratiolevels

ofmeasurement.SIXDefinethetermsmutuallyexclusiveandexhaustive.GOALSWhenyouhavecompletedthischapter,youwillbeableto:2Whystudystatistics?NumericalinfoiseverywhereButhowdoweknowifconclusionsreportedareaccurate?StatisticaltechniquesareusedtomakedecisionsthataffectourlivesThisiswhyyoungerpeoplepaymoreforinsurance…KnowledgeofstatisticalmethodsatleasthelpsyouunderstandwhydecisionsaremadeInfutureyouwillmakedecisionsthatinvolvedata3WhatisMeantbyStatistics?

Statistics

isthescienceofcollecting,organizing,presenting,analyzing,andinterpretingnumericaldatatoassistinmakingmoreeffectivedecisions.

Incommonusagestatisticsreferstonumericalinformation…..Butinthiscoursethetermhasawidermeaning….4WhoUsesStatistics?

Statisticaltechniquesareusedextensivelybymanagersinmarketing,accounting,qualitycontrol,consumers,professionalsportspeople,hospitaladministrators,educators,politicians,physicians,gamblers,etc...5TypesofStatistics

DescriptiveStatistics:Methodsoforganizing,summarizing,andpresentingdatainaninformativeway.EXAMPLE1:AGalluppollfoundthat49%ofthepeopleinasurveyknewthenameofthefirstbookoftheBible.Thestatistic49describesthenumberoutofevery100personswhoknewtheanswer.6TypesofStatistics

DescriptiveStatistics:Methodsoforganizing,summarizing,andpresentingdatainaninformativeway.EXAMPLE2:AccordingtoConsumerReports,GeneralElectricwashingmachineownersreported9problemsper100machinesduring2002.Thestatistic9describesthenumberofproblemsoutofevery100machines.7TypesofStatistics

DescriptiveStatistics:Methodsoforganizing,summarizing,andpresentingdatainaninformativeway.EXAMPLE3:TheCanadiangovernmentreportsthatthepopulationofCanadawas18,238,000in1961,21,568,000in1971,24,820,000in1981,28,031,000in1991,and31,050,700in2001.Ifwecalculatepercentagegrowthoverthedecadesitisalsodescriptivestatistics.8TypesofStatistics

InferentialStatistics:Themethodsusedtodeterminesomethingaboutapopulation,basedonasample.

O

EXAMPLE1:IntheprecedingexampleonCanadianpopulationchanges,ifyouusethepastdatatoforecastthepopulationofCanadaintheyear2010orexpectedpercentageofgrowthfrom2000to2010,thenthisisconsideredinferentialstatistics.9TypesofStatistics

InferentialStatistics:Themethodsusedtodeterminesomethingaboutapopulation,basedonasample.

EXAMPLE2:Theaccountingdepartmentofalargefirmwillselectasampleoftheinvoicestocheckforaccuracyforalltheinvoicesofthecompany.10TypesofStatisticsInferentialStatistics:Themethodsusedtodeterminesomethingaboutapopulation,basedonasample.EXAMPLE3:Winetasterssipafewdropsofwinetomakeadecisionwithrespecttoallthewinewaitingtobereleasedforsale.11Populationvs.SamplePopulationistheentiresetofindividualsorobjectsofinterestorthemeasurementsobtainedfromallindividualsorobjectsofinterest.Sampleisaportion,orpart,ofthepopulationofinterest12Seealsop.7Population:AllitemsSample:Itemsselectedfromthepopulation13NB:don’tconfusepopulationinstatisticswithacountry’’spopulation!ApopulationmightconsistofallthepeopleinNanaimobutalsomaymeanthePEratiosforallchemicalstocks,ortotalassetsofthe20largestbanksinNorthAmerica,totalcollectionofprices,ages,squarefootageofretailspaceinNanaimo,andsoon.14TypesofVariablesForaQualitativeorAttributevariablethecharacteristicbeingstudiedisnonnumeric.EXAMPLES:Gender,religiousaffiliation,typeofautomobileowned,countryofbirth,eyecolourareexamples.15TypesofVariablesInaQuantitativevariableinformationisreportednumerically.EXAMPLES:balanceinyourchequingaccount,minutesremaininginclass,ornumberofchildreninafamily.16TypesofVariablesQuantitativevariablescanbeclassifiedaseitherdiscreteorcontinuous.Discretevariables:canonlyassumecertainvaluesandthereareusually““gaps””betweenvalues.EXAMPLE:thenumberofbedroomsinahouse,orthenumberofhammerssoldatthelocalHomeDepot(1,2,3,……,etc).Butyoucannothave2.3bedroomsor10.6hammers…Thusdiscretevariablesresultfromcounting.17TypesofVariablesAcontinuousvariablecanassumeanyvaluewithinaspecifiedrange.Examplesare:Thepressureinatire,theweightofaporkchop,ortheheightofstudentsinaclass.Typically,continuousvariablesaretheresultofmeasuringsomething.18SummaryofTypesofVariables19LevelsofMeasurementDatamaybeclassifiedintofourclassesorlevelsofmeasurement:nominal,ordinal,interval,andratio.Nominallevel:Datathatisclassifiedandcounted.EXAMPLES:eyecolour,gender,religiousaffiliation.20LevelsofMeasurementMutuallyexclusive:Anindividual,object,ormeasurementisincludedinonlyonecategory.Exhaustive:Eachindividual,object,ormeasurementmustappearinoneofthecategories.Nominaldatahavenoparticularorderorrankandaremutuallyexclusive.21MaritalStatus2000(population15yearsandolder)StatusNumberSingle(nevermarried)7,285,560Married(legally,separated,common-law)14,614,564Divorced1,452,000Widowed1,527,075Total24,879,199Thesedataareanominallevelofmeasurementbecauseitcanonlybeclassifiedintoclassesandtheorderofthemaritalstatusisnotimportant.Theclassesarealsomutuallyexclusiveandexhaustive.22LevelsofMeasurementOrdinallevel:involvesdataarrangedinsomeorder,butthedifferencesbetweendatavaluescannotbedeterminedoraremeaningless.EXAMPLE:Duringatastetestof4softdrinks,MountainDewwasrankednumber1,Spritenumber2,Seven-upnumber3,andOrangeCrushnumber4.23LevelsofMeasurementIntervallevelissimilartotheordinallevel,withtheadditionalpropertythatmeaningfulamountsofdifferencesbetweendatavaluescanbedetermined.Thereisnonaturalzeropoint.EXAMPLE:TemperatureontheCelsiusscale.0degreesdoesnotrepresenttheabsenceoftemperature,justthatitiscold!24LevelsofMeasurementRatiolevelistheintervallevelwithaninherentzerostartingpoint.Differencesandratiosaremeaningfulforthislevelofmeasurement.EXAMPLES:Monthlyincomeofsurgeons,ordistancetraveledbymanufacturer’’srepresentativespermonth.2526272829309、静夜四无邻邻，荒居旧业业贫。。12月-2212月-22Friday,December23,202210、雨中黄叶树树，灯下白头头人。。07:03:5407:03:5407:0312/23/20227:03:54AM11、以以我我独独沈沈久久，，愧愧君君相相见见频频。。。。12月月-2207:03:5407:03Dec-2223-Dec-2212、故故人人江江海海别别，，几几度度隔隔山山川川。。。。07:03:5407:03:5407:03Friday,December23,202213、乍见见翻疑疑梦，，相悲悲各问问年。。。12月月-2212月月-2207:03:5407:03:54December23,202214、他乡乡生白白发，，旧国国见青青山。。。23十十二月20227:03:54上午午07:03:5412月-2215、比不了得得就不比，，得不到的的就不要。。。。十二月227:03上上午12月-2207:03December23,202216、行动出成成果，工作作出财富。。。2022/12/237:03:5407:03:5423December202217、做前，能能够环视四四周；做时时，你只能能或者最好好沿着以脚脚为起点的的射线向前前。。7:03:54上上午7:03上上午07:03:5412月-229、没有失败，，只有暂时停停止成功！。。12月-2212月-22Friday,December23,202210、很多事情努努力了未必有有结果，但是是不努力却什什么改变也没没有。。07:03:5407:03:5407:0312/23/20227:03:54AM11、成功功就是是日复复一日日那一一点点点小小小努力力的积积累。。。12月月-2207:03:5507:03Dec-2223-Dec-2212、世间成事事，不求其其绝对圆满满，留一份份不足，可可得无限完完美。。07:03:5507:03:5507:03Friday,December23,202213、不知香积积寺，数里里入云峰。。。12月-2212月-2207:03:5507:03:55December23,202214、意意志志坚坚强强的的人人能能把把世世界界放放在在手手中中像像泥泥块块一一样样任任意意揉揉捏捏。。23十十二二月月20227:03:55上上午午07:03:5512月月-2215、楚楚塞塞三三湘湘接接，，荆荆门门九九派派通通。。。。。十二二月月227:03上上午午12月月-2207:03December23,202216、少少年年十十五五二二十十时时，，步步行行夺夺得得胡胡马马骑骑。。。。2022/12/237:03:5507:03:5523December202217、空山山新雨雨后，，天气气晚来来秋。。。7:03:55上上午7:03上上午午07:03:5512月月-229、杨柳散散和风，，青山澹澹吾虑。。。12月-2212月-22Friday,December23,202210、阅读一一切好书书如同和和过去最最杰出的的人谈话话。07:03:5607:03:5607:0312/23/20227:03:56AM11、越是没有本本领的就越