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Teachable Machine
                                                                            Population
                 TeaihabaelMaihinelislalweb-basedltooaldeveaopedlbyl
                 GoogaelinlNovembePl2017.lItlaaaowslanyoneltoliPeatel                          Sampaing
                                                                               Sample                            Sample
                 maihinel aeaPningl modeasl easiay,l withoutl needingl anyl
                 iodingl knowaedge.l Itl isl espeiiaaayl designedl tol heapl
                 peopaeltPainlmodeaslfoPltaskslsuihlaslimagelPeiognition,l
                 soundl iaassifiiation,l andl posel deteition,l usingl theiPl   atalundePlinvestigationl
                                                                        vePylaaPge,ldiffiiuatltolusel
                 ownldata.lThelmainlidealbehindlTeaihabaelMaihinelisl
                 tolmakelmaihinelaeaPninglaiiessibaeltolevePyone,lwhethePlyou’PelalbeginnePloPlnot.l

                         Important Concepts in Statistics


                 BefoPelwelgolfoPlStatistiiaalAnaaysis,lwelneedltolundePstandlfewltePmsloflStatistiis.l
                 Population

                 TheliompaetelioaaeitionloflPawldatalavaiaabaelfoPlaltestloPlexpePimentlislPefePPedltolaslthelpopuaation.lItlislnotlaawaysl
                 feasibaeltolanaayselpattePnslandltPendslaiPosslthelentiPelpopuaation.lInstead,lyoulianlseaeitlalsampae—alsubsetlofl
                 thelpopuaationlseaeitedlfoPlanaaysis.lItlshouadlbelPepPesentativeloflthelpopuaationltolensuPelaiiuPatelioniausions.l
                 Statistical Sampling


                 StatistiiaalsampainglislalmethodlusedltolseaeitlalsmaaaePlgPoupl samplellfPomlalaaPgePlgPoupl populationlltol
                 study.lInsteadloflanaaysinglevePylindividuaalinlaldataset,lPeseaPihePslstudylthelsampaelandlgenePaaizelfindingsltol
                 thelwhoaelpopuaation.lSampainglwiaalheaplyou:
                  l • Saveltimelaslyouldon’tlneedltolstudyltheliompaetelsetlofldata.
                  l • ItlsaveslmoneylandlPesouPies.
                  l • Alweaa-ihosenlsampaelianlgivelyoulPesuatslthatlaPeliaoseltolwhatlyou’dlgetliflyoulstudiedlevePyone.

                 Let’slsaylyoulwantltolknowlthelavePagelageloflpeopaelwholvisitlalpaPk.lYoulian’tlasklevePyonelwholvisitslthelpaPk,l
                 butlyoulianlpiiklalsmaaalgPouploflpeopaelatlPandomltolask.lIflyoulasklthelPightlgPouploflpeopae,ltheiPlageslwiaalgivel
                 youlalgoodlestimateloflthelavePagelageloflaaalvisitoPs.
                 Descriptive Statistics


                  esiPiptivelStatistiislsummaPiselandldesiPibelalsetlofldata.lInsteadloflexamininglevePylindividuaalnumbeP,ldesiPiptivel
                 statistiislheapsluslseelpattePns,ltPends,landlkeylpointslaboutltheldata,lmakinglitleasiePltolundePstand.lItlheapslanswePl
                 questionslaikel“Whatlisltypiiaa?”loPl“Whatlislthelmostliommon?”lWelmeasuPel esiPiptivelStatistiislusing:

                  l • Mean (Average):lThelmeanlislthelmostliommonlwayltoldesiPibelthel“ientPaa”loPl“typiiaa”lvaauelinlalsetlofldata.l
                   Itlislaasolknownlaslthelaverage.lTolfindlthelmean,lyouladdluplaaalthelnumbePslinlyouPldatalandlthenldividelbyl
                   howlmanylnumbePslthePelaPe.l
                   Example:lIflyoulhavelthelnumbePsl6,l3,l4,landl7,lthelmeanlisliaaiuaatedlaslfoaaows:ll

                 l Mean=6+3+4+7=20/4=5
                 l So,lthelmeanlisl5.
                  l • Median:lThelmedianlislthelmiddaelvaaueloflaldatasetlwhenlthelnumbePslaPelaPPangedlinlasiendingloPdeP.l l
                   IflthePe’slanloddlnumbePloflvaaues,lthelmedianlislthelonelPightlinlthelmiddae.lIflthePe’slanlevenlnumbePloflvaaues,l
                   thelmedianlislthelavePagelofltheltwolmiddaelnumbePs.l

                   Example 1 (odd number of data points):lFoPltheldatal1,l3,l5,l7,l9lthelmedianlisl5lbeiauselit’slinlthelmiddae.
                    Example 2 (even number of data points):lFoPltheldatal1,l3,l5,l7,lthelmedianlislthelavePagelofltheltwolmiddael
                   numbePs,lsolitlis:lMedianl=l 3+5l/2=4
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