stats analysis template_v0.2.pptx

CaseStudyofDataAnalysis EthanSunversion1 观察非正态分布的对象 Themeanisquitedifferentfromthemedian suggestingthatthedistributionisasymmetric Thissuspicionisconfirmedbythelargepositiveskewness whichshowsthatsalesdatahasalongrighttail Thatis thedistributionisasymmetric Thelargepositiveskewness inadditiontoskewingthemeantotherightofthemedian inflatesthestandarddeviationtoapointwhereitisnolongerusefulasameasureofthespreadofdatavalues Thelargepositivekurtosistellsyouthatthedistributionofsalesdataismorepeakedandhasheaviertailsthanthenormaldistribution Skewness 远大于0 右长尾巴Kurtosis 远大于0 比ND尖很多 找到最重要的数据 屏蔽干扰 Wirelessandequipmentrentalservicesbringinfarmorerevenuepercustomerthanotherservices Moreover whilewirelessserviceremainsahighvariableprospect equipmentrentalhasoneoftheloweststandarddeviationsThishasn tsolvedtheproblemofwhopurchasestheseservices butitdoespointyouinthedirectionofwhichservicesdeservegreatermarketing Corncropsmustbetestedforaflatoxin apoisonwhoseconcentrationvarieswidelybetweenandwithincropyields Agrainprocessorhasreceivedeightcropyields butthedistributionofaflatoxininpartsperbillion PPB mustbeassessedbeforetheycanbeaccepted AccordingtoU S law ayieldisunfitforhumanconsumptionifaflatoxinexceeds20PPB Thepivotedtablemakesitclearthatinthesedata onlyyields4 7 and8fallbelowthe20PPBcutoff 分组的描述统计 直观的分析 探索性分析 未知分布的初探 Amanufacturingfirmusessilvernitridetocreateceramicbearings whichmustresisttemperaturesof1500degreescentigradeorhigher Theheatresistanceofastandardalloyisknowntobenormallydistributed However anewpremiumalloyisundertest anditsdistributionisunknown Thisisstrongevidencethatheatresistanceinstandardbearingsisnormallydistributed Themeanishigherthaneitherthetrimmedmeanorthemedian outliersorextremevaluesarepullingitupward Theskewnessandkurtosisstatisticsalsoprovideevidenceofdisproportionatevaluesattheuppertailofthedistribution Mean 1542 08 Median 1539 72M estimate Mean 同时接近与Median 更加说明 右偏的值使得mean比median大 探索性分析 观察极值 Sig forPremium 0 05 rejectH0 既distributionofpremiumalloydataisnotnormaldistribution ExtremevaluesLeft and stemchart aQ Qplotisdisplayed Thestraightlineintheplotrepresentsexpectedvalueswhenthedataarenormallydistributed Theobservedpremiumbearingvaluesdeviatemarkedlyfromthatline especiallyastemperatureincreases 探索性分析 利用Q Q 尽管这两个变量之间看似存在某种关系 但有没有任何理由可以认为不同收入类别之间PDA拥有数量的差异不仅仅是随机变异呢 许多检验方法可用于确定两个交叉制表的变量之间的关系是否显著 其中一种较常用的检验方法是卡方 卡方的优点之一是它几乎适合任何类型的数据 在此情况下 显著性值非常低 显示为 000 这意味着 它显示两个变量实际上是相关的 列联表分析 列变量和变量是否有关系 变量1 变量2 当数据的衡量水平是nominal或者ordinal 而且数值由每个分类中事件发生的次数决定时 使用列联表分 交叉表格 析 交叉的关系是否符合期望 变量之间没有联系 这表明 收入和PDA拥有者之间的明显关系仅仅是教育水平与PDA拥有者之间的潜在关系的产物 由于收入会随受教育水平的提高而提高 所以收入和其他变量之间的明显关系可能实际上是教育差异的结果 列联表分析 深入一层另有玄妙 X tabs变量关系 onelayerdeeper 均值比较和T检验 均值分析 自变量 因变量 CaseBackgroundAmanufacturerofhigh performanceautomobilesproducesdiscbrakesthatmustmeasure322millimeters 预设值 indiameter Qualitycontrolrandomlydraws16discsmadebyeachof8 分组 productionmachinesandmeasurestheirdiameters Tdistributiontest Ho samplemeanofeachgroup 322Ha notequalCriticalValue 0 10 x2 0 2 Analysisresult Machine2 5 7 8isnotqualifiedsignificantlyMachine4isnotqualifiedslightly T分布的分组检测 预设标准 Aphysicianisevaluatinganewdietforherpatientswithafamilyhistoryofheartdisease Totesttheeffectivenessofthisdiet 16patientsareplacedonthedietfor6months Theirweightsandtriglyceridelevelsaremeasuredbeforeandafterthestudy andthephysicianwantstoknowifeithersetofmeasurementshaschanged Ontheotherhand thePearsoncorrelationbetweenthebaselineandsix monthweightmeasurementsis0 996 almostaperfectcorrelation Unlikethetriglyceridelevels allsubjectslostweightanddidsoquiteconsistently 配对的差异检测 相同物体的不同环境 Onewayanalysisofvariances Asalesmanagerwishestodeterminetheoptimalnumberofproducttrainingdaysneededfornewemployees Hehasperformancescoresforthreegroups employeeswithone two orthreedaysoftraining 培训分数和培训天数的关系 1st量化图像 显示均值与2个标准差的数据2nd选择onewayavova检测3rd结果 随着trainingdays的增加 performancescores变高 好 且stddeviation变小 也就是组内差异变小 好 levenetest显示0 014 0 10 组间差异显著 比较组间均值是否有差异的方法 DVDscore Inresponsetocustomerrequests anelectronicsfirmisdevelopinganewDVDplayer Usingaprototype themarketingteamhascollectedfocusgroupdata ANOVAisbeingusedtodiscoverifconsumersofvariousagesreacted ratedthedesigndifferently Factor affects Themeansplothelpsyouto see thisstructure Participantsbetweentheagesof35and54ratedtheDVDplayermorehighlythantheircounterparts Ifmoredetailedanalysesaredesired thentheteamcanusetherangetests pairwisecomparisons orcontrastfeaturesinOne WayANOVA 一般方法 首先证明各组的反馈是有差异的 再图示这种差异 组间meansquare除以组内meansquare的Fvalue很大 组间均值差异显著 图示组间的均值差异 AVOVA功能 任意组的均值比较 继续前例 做两种比较 比较1 只比较agegroup35 44以及45 54是否有显著差异比较2 比较34岁以下与55岁以上 俩俩组合起来一起进行比较 是否有显著差异 分析结果 agegroup35 44和45 54没有显著对dvdplayer的评分差异 且34岁以下与55岁以上也没有显著差异 差异理解为抽样误差 商业建议 重点对35 54的人 也就是对dvd评分高的人群 制定针对性地营销计划 因为他们更有可能购买产品 针对其他人群 调查为何评分不高的原因 已改进产品 OnewayAVOVA其他计算方法 Solutionmakesimprovements Onecontractcreatedforeachopportunity Changeofcontractsizeaftersplittingbids A3 Lineitemdistributionforexistingandafter splitcontracts ofcontracts Aftercontractsplit 189 158 Existingcontracts 1 663 100 4 15 42 Aftercontractsplit 100 1 1 Existingcontracts Lineitemdistributionforexistingandafter splitcontracts Percentageofcontracts 400 300 400 200 300 100 200 50 100 0 50 Datasource GAOdatateamprovidedthedataanalysisbasedoncontractmigrationapproach Total 8k Total 192k CurrentsituationAs IsAnalysis AftersolutionappliedTo Beanalysis comparisons ConclusionBenefitsofthenewsolution IllustrationofAs isandTo becomparisons Contractmigrationtimingoptions BusinessandITimpactandfeasibility Pros Cons Feasibility Hitstrategiccountries businessbeforeW2go liveDuplicatecontractsearchresultsinLPOSinterfaceforEMindirectchannel MigratecontractsbybatchandcutoffGAOuploadsolutioninStrategiccountriesonlybeforeW2golive Description DuplicatesearchresultsinLPOSinterfaceforEMindirectchannelChange go livetogetherwithaccountramp up MigratecontractsbybatchstartingfromOct Maintaindualsystemsuntilaccountramp upafterW2 MigratecontractsbybatchstartingfromDec Maintaindualsystemsuntilaccountramp upafterW2 Contractmigrationandchange go livetogetherwithaccountramp upNeedtosynchronizemulticontractdataextract loadswithrampupplan Migratecontractstogetherwithaccountramp upafterW2go live Pros Cons Feasibility ManageableimpactonCRMperformance2setsofcontractstomaintainforlegacycountriesfor4months 2setsofcontractstomaintainforeverycountryfor4months CRMperformancebecomepoorduetohighvolume intensecontractmigrationinshorttimeframe Minimizeddual systemmaintenancerequiredHeavilyrelyonbusinessrampupplan Businessimpact ITimpact DuplicatesearchresultsinLPOSinterfaceforEMindirectchannelChange go livetogetherwithaccountramp up B High levelstrategyselectionmodel Potentialbusinessimpactduetocontractnumberincrease Impactarea Contractcreation Contractamendment e g PN EoL 3 Changeimpact Anewcontractneedstobecreatedinsteadofrevisingtheexistingcontracts SalesneedtosearchcontractsbyPNinsteadoflookinginonemastercontract ICOcatalogcreation Existingtoolscanaggregatelargenumberofcontracts CRMWebUI e g ISR CSO LPOS 75 EPRcontractswereindirectcontracts Externalweb EDI Onlyonevalidcontractwillbefilteredoutanddisplayed PNlinktocontractistransparent Webcataloglinktocontractsistransparent Noimpact Highimpact MG OnlyonevalidcontractwillbefilteredoutanddisplayedEM CPneedstomanuallylookthroughalargenumberofcontractstofindthePNsandplaceonePOforonecontract Contractsearch Searchtoolsexist butneedtoofferpropertrain