Cov txheej txheem:
Video: Cov mis rau ntawm kev xeem yog dab tsi?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Qhov t xeem statistic tus nqi rau xeem seb cov txhais tau li cas sib txawv tuaj yeem xam raws li hauv qab no: t=mA−mB√S2nA+S2nB. S2 yog qhov kwv yees ntawm qhov sib txawv ntawm ob qho piv txwv. Nws tuaj yeem suav tau raws li hauv qab no: S2 = ∑(x−mA)2+∑(x−mB)2nA+nB−2.
Tsuas yog li ntawd, koj siv cov qauv t xeem li cas?
T-Test Formula
- overline{x} = Lub ntsiab lus ntawm thawj cov nqi.
- overline{x}_{2} = Lub ntsiab lus thib ob ntawm qhov muaj nuj nqis.
- S_{1} = Tus qauv sib txawv ntawm thawj txheej ntawm qhov tseem ceeb.
- S_{2} = Tus qauv sib txawv ntawm qhov thib ob ntawm qhov tseem ceeb.
- n_{1} = Tag nrho cov nqi hauv thawj txheej.
- n_{2} = Tag nrho cov nqi ntawm qhov thib ob.
Ib sab saum toj no, T xeem siv rau dab tsi? A t - xeem yog ib hom inferential statistic siv rau txiav txim siab seb puas muaj qhov sib txawv tseem ceeb ntawm txoj kev ntawm ob pawg, uas tej zaum yuav muaj feem cuam tshuam nrog qee yam nta. A t - xeem yog siv li ib hypothesis kuaj cuab tam, uas tso cai kuaj ntawm ib qho kev xav muaj feem xyuam rau cov pej xeem.
Tib neeg kuj nug, koj ua li cas suav ib qho qauv t xeem?
Cov ib t test piv cov ntsiab lus ntawm koj qauv cov ntaub ntawv rau tus nqi paub. Rau piv txwv , tej zaum koj yuav xav paub seb koj li cas qauv txhais tau tias piv rau cov pejxeem txhais tau tias.
Ib qho piv txwv T Test
- Tus qauv txhais tau tias(x¯).
- Cov pejxeem txhais tau tias (μ).
- Tus qauv qauv sib txawv = $ 15.
- Number of observations(n) = 25.
AF test yog dab tsi?
Ib F - xeem yog ib qho kev txheeb cais xeem hauv qhov twg xeem statistic muaj ib F -Kev faib tawm raws li qhov kev xav tsis tseeb. Nws yog feem ntau siv thaum sib piv cov qauv kev txheeb cais uas tau muab tso rau hauv cov ntaub ntawv teeb tsa, txhawm rau txheeb xyuas cov qauv uas haum rau cov pej xeem los ntawm cov ntaub ntawv tau coj mus kuaj.
Pom zoo:
Dab tsi yog qhov sib txawv ntawm cov alleles ntawm cov tib neeg hauv cov pej xeem hu ua?
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