Mann-Whitney yokuhlola: ithebula isibonelo

Lokunquma e izibalo zezibalo - umthetho eziqinile, ngokuhambisana umbono wokuthi izinga elithile ukubaluleka samukelwe noma sinqatshelwe. Ukwakha, udinga ukuthola umsebenzi othile. Kufanele kuxhomeke Imiphumela sokugcina sokuhlola, okungukuthi, kusukela amagugu empirically uzimisele. Kuyinto lesi sici kuzoba yithuluzi ukuhlola umehluko phakathi amasampula.

Inani wezibalo obalulekile. Uhlolojikelele

ukubaluleka kwezibalo - ukubaluleka ematfuba ithuba nesenzakalo sincane kakhulu. Ongabalulekile njengoba ngokwedlulele kanye nokusebenza yayo. Umehluko libizwa wezibalo obalulekile esimweni lapho kukhona idatha, ematfuba lapho azinakwa uma isimangalo sokuthi mehluko abekho. Kodwa lokhu akusho ukuthi lo mehluko kumelwe nakanjani ube mkhulu futhi abalulekile.

Izinga kwezibalo ukubaluleka kokuhlolwa

Leli gama kufanele kuvisiswe Cishe senqabe umbono null esimweni iqiniso layo. Lokhu futhi kuthiwa yi nephutha uhlobo lokuqala, noma isinqumo okungelona iqiniso. Ezimweni eziningi, le nqubo kusekelwe p-value ( "pi-value"). Lokhu okungenzeka ezuziwe ngokuqaphela ezingeni ukuhlolwa kwezibalo. Yena, has isampula ngesikhathi kwamukelwa hypothesis null. Isiphakamiso kuzonqatshelwa uma p-value ingaphansi limenyezelwe ezingeni umhlaziyi. Kule sibalo incike ngqo amagugu ukubaluleka kokuhlolwa: ezincane kangaka, ngokulandelana, futhi isizathu ngaphezulu ukwenqaba umbono. Izinga ukubaluleka ngokuvamile yi- incwadi B (i-alpha). izibalo Idumile Ochwepheshe: 0.1%, 1%, 5% no-10%. Uma, ukwenza isibonelo, wathi ukuthi amathuba ukufana kukhona 1 e 1,000 ke nakanjani sikhuluma mayelana 0.1% izinga olubaluleke kwezibalo kwenombolo engahleliwe. nezincazelo ezahlukene b-amazinga kufanele elithola abo kanye nebubi. Uma Inkomba kancane ke maningi amathuba okuba umbono okunye libalulekile. Nakuba lokhu kungaba ingozi ukuthi amanga null hypothesis is ngikwale. It lingahunyushwa baphetha ukuthi kukhethwa elilungile b-level incike ibhalansi "ukubaluleka amandla" noma, ngokulandelana, ematfuba ukuhlehla a izinqumo okungamanga neyamanga ezimbi. Lahlotshaniswa nokuba "ukubaluleka kwezibalo" ezincwadini Russian leli gama "ubuqiniso".

Ukunqunywa umbono null

Ngo izibalo zezibalo, lokhu nokucabanga is kuhlolelwe nokungaguquki ubufakazi ezikhona enokwehla esandleni. Ezimweni eziningi, umbono null esithathwayo umbono wokuthi ukuhlanganisa phakathi eziguquguqukayo cwaningo alitholakali noma ukuthi akudingeki ukuba batadishe umehluko ukusatshalaliswa ukufana. Ngaphansi izinga ucwaningo sezibalo uzama siphikise null umbono, okungukuthi, ukuze kuqinisekiswe ukuthi awuhambisani nalokho okutholwe zokuhlola. Futhi ukuthatha indawo kanye umbono okunye ukuthi yamukelwe esikhundleni zero.

izincazelo ukhiye

Lokunquma U (Mann-Whitney) e izibalo zezibalo ivumela ukuhlola umehluko phakathi amasampula amabili. Bangazinika ezingeni trait kukalwa quantitatively. Le ndlela kuyinto ekahle kokuhlaziywa kwamathenda umehluko amasampuli encane. Lokhu umbandela elula kwahlongozwa kaFrank Wilcoxon ngo-1945. Futhi ngo-1947, indlela iye olubukeziwe kulekelelwa ososayensi H. B. Mann no D. R. Uitni, amagama okuyinto ubizwa ngokuthi kuze kube yilolu suku. Mann-Whitney test kwengqondo, izibalo, izibalo nezinye izinhlobo zesayensi eziningi ingenye izakhi eyisisekelo isisekelo zezibalo zocwaningo theory.

incazelo

Mann-Whitney - indlela elula ngaphandle imingcele. umthamo wayo libalulekile. Kuyinto siphezulu kunamanye amandla Rosenbaum Q-test. Indlela Uhlaziya indlela encane endaweni cross-amanani phakathi amasampula, okungukuthi phakathi imigqa lamanani oluhleliwe okukhethiwe lokuqala nelesibili. Inani ingaphansi umbandela, cishe ukuthi amagugu ipharamitha umehluko evumelekile. Ukuze ukwazi ukufaka isicelo kahle umbandela U (Mann-Whitney), ungakhohlwa mayelana neminye imikhawulo. isampula ngasinye kufanele okungenani 3 isici value. Kungenzeka ukuthi kwelinye icala amagugu ezimbili, kodwa sikhathi saphinda okwesibili ngempela kumele okungenani ibe ezinhlanu. Esikhathini amasampula yokuhlola kumele kube inombolo okungenani izinkomba coincident. Zonke izinombolo kufanele ihluke esimweni ekahle.

ukusetshenziswa

Indlela efanele ukusebenzisa isivivinyo Mann-Whitney? Ithebula, okuyinto eyenziwe le ndlela yakhiwa inani elithile ezibucayi. Okokuqala udinga ukudala iqoqo elilodwa amasampula amabili ifaniswe, abese zibalwa. Okungukuthi, abangabantwana izakhi ahlelwe ngokusho degree of nesanda sici futhi isikhundla aphansi inikezwa nenani ezincane. Ngenxa yalokho, sithola lonke inani amamaki:

N = uN1 + N2,

lapho amagugu N1 N2 - isibalo amayunithi eziqukethwe amasampula lokuqala nelesibili ngokulandelana. Ngaphezu kwalokho, olulodwa zibalwa amagugu inombolo uhlukaniswe izigaba ezimbili. Amayunithi, ngokulandelana, amasampula lokuqala nelesibili. Manje kubhekwe e ujike isamba sabantu bezigaba yamanani imigqa yokuqala neyesibili. It kunqunywa iningi labo (Tx), okuhambelana isampula nge nx amayunithi. Ukusebenzisa indlela Wilcoxon ngaphezulu, inani layo ibalwa ngu inqubo elandelayo. Kubalulekile etafuleni ukuze kutholakale izinga ekhethiwe ukubaluleka umbandela esibucayi uN1 ngokuqondile ezithathwe ne-N2. Uphiko okuholela kungaba ngaphansi noma ilingane nenani kusuka etafuleni. Kulokhu, umehluko okukhulu is ukubuzisisa amazinga sici isampuli wafunda. Uma ukubaluleka okuholela mkhulu etafuleni ke umbono null samukelwa. Lapho ukubala wenziwa Mann-Whitney test, kufanele kuphawulwe ukuthi uma umbono null kuyiqiniso, umbandela kuyoba luwukulindelwa, kanye ukuhlakazwa. Qaphela ukuthi i-lemiqulu emikhulu amasampula idatha indlela kubhekwa ukusatshalaliswa cishe evamile. Ukubaluleka umehluko lingaphezulu, ukubaluleka iba sakugcina Mann-Whitney test.