Video: Dab tsi yog qhov sib txawv ntawm qhov sib txawv ntawm cov kab sib txuas thiab ntau qhov sib piv?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
6. (2 teev) Dab tsi yog qhov sib txawv ntawm cov kab sib txuas ( contrasts) thiab ntau qhov sib piv ? Kev sib xyaw ua ke tau npaj kev sib piv ; uas yog, tshwj xeeb txhais tau tias yog ua ke nyob rau hauv txawv txoj kev thiab sib piv nrog rau lwm yam kev sib xyaws ntawm txhais tau tias.
Ntawm no, qhov sib txawv linear yog dab tsi?
Hauv kev txheeb cais, tshwj xeeb hauv kev txheeb xyuas qhov sib txawv thiab kab tawm regression, ib sib piv yog a kab tawm kev sib xyaw ua ke ntawm kev sib txawv (tsis muaj los yog txheeb cais) uas nws cov coefficients ntxiv mus rau xoom, tso cai rau kev sib piv ntawm cov kev kho mob sib txawv.
Tsis tas li, yuav ua li cas ntau qhov kev sib piv tshwm sim hauv ib qho kev sim? Muaj ntau qhov kev sib piv thaum muaj kev txheeb xyuas kev txheeb cais ntau simultaneous statistical xeem, txhua tus muaj peev xwm rau tsim ib qho "discovery", ntawm tib dataset lossis nyob ntawm cov ntaub ntawv.
Qhov thib ob, txoj kev sib piv ntau yam yog dab tsi?
Kev sib piv ntau xeem cov txheej txheem xav tau. Ib txoj hauv kev nrov los tshawb xyuas qhov ua rau tsis lees paub qhov kev xav tsis zoo yog a Cov txheej txheem sib piv ntau . Cov no yog cov txheej txheem uas tshuaj xyuas lossis sib piv ntau dua ib khub ntawm txhais tau tias lossis kev faib ua feem tib lub sijhawm.
Dab tsi yog qhov txawv ntawm qhov kev xeem tom qab hoc thiab kev npaj sib piv?
Post hoc xeem feem ntau yog siv los ntsuas cov khub ntawm pawg saib seb lawv puas tseem ceeb ntawm ib leeg. Tsis zoo li npaj sib piv , cov kev ntsuam xyuas no tsis yog npaj rau hauv ua ntej, tab sis theej sawv cev rau kev tshawb fawb "tom qab qhov tseeb" kom pom qhov twg qhov tseem ceeb sib txawv muaj.
Pom zoo:
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