Video: Dab tsi yog qhov kev faib tawm ib txwm nyob hauv kev txheeb cais?
2024 Tus sau: Stanley Ellington | [email protected]. Kawg hloov kho: 2023-12-16 00:17
A kev faib khoom ib txwm muaj muaj lub tswb-shaped curveandis symmetrical nyob ib ncig ntawm nws qhov chaw, yog li sab xis ntawm lubcenteris daim iav duab ntawm sab laug. Feem ntau ntawm cov nruam datavalues hauv a kev faib khoom ib txwm muaj zoo li pawg nyob ib ncig ntawm lub ntiaj teb, thiab tus nqi ntxiv yog los ntawm qhov txhais tau tias, qhov tsawg dua yuav tshwm sim.
Yog li, dab tsi yog qhov kev faib tawm ib txwm nyob hauv kev txheeb cais cov ntsiab lus?
A kev faib khoom ib txwm muaj yog ib qho kev npaj ntawm adataset uas feem ntau muaj nuj nqis pawg hauv nruab nrab ntawm cov ntau yam thiab tus so taper tawm symmetrically mus rau ob qho tag nrho. Cov duab meej yuav txawv raws li qhov kev faib tawm ntawm cov pejxeem tab sis lub ncov yog ib txwm nyob rau hauv nruab nrab thiab qhov nkhaus yog ib txwm sib luag.
Ib tug kuj yuav nug, dab tsi yog qhov zoo tshaj plaws kev faib tawm? Txij li thaum " zoo tag nrho " kev faib khoom ib txwm muaj yuav luag tsis tshwm sim hauv cov ntaub ntawv tiag tiag (qhov twg " zoo tag nrho " normaldistribution yog txhais raws li 1. lub kev faib tawm yog zoo kawg nkaus symmetrical ntawm txhua tus qauv sib txawv ntawm ob sab ntawm qhov nruab nrab, thiab 3.
Kuj paub, dab tsi yog cov khoom ntawm ib txwm faib hauv kev txheeb cais?
Cov yam ntxwv ntawm NormalDistribution Kev faib tawm ib txwm yog symmetric, unimodal, andasymptotic, thiab qhov nruab nrab, nruab nrab, thiab hom yog sib npaug. A kev faib khoom ib txwm muaj yog zoo kawg nkaus symmetrical arounditscenter. Ntawd yog, sab xis ntawm qhov chaw nruab nrab yog daim iav duab ntawm sab laug.
Dab tsi yog qhov kev faib tawm hauv qhov tshwm sim?
Qhov yuav tshwm sim thiab cov NormalCurve Cov kev faib khoom ib txwm muaj yog tsis tu ncua qhov yuav faib . Qhov no muaj ntau yam cuam tshuam rau qhov tshwm sim . Tag nrho cheeb tsam nyob rau hauv lub ib txwm nkhaus sib npaug rau 1. Cov qhov tshwm sim tias a li qub randomvariable X sib npaug txhua tus nqi tshwj xeeb yog 0.
Pom zoo:
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Nyob rau hauv kev txheeb cais, sampling bias yog ib tug bias nyob rau hauv uas ib tug piv txwv yog sau nyob rau hauv xws li ib tug txoj kev uas ib co tswv cuab ntawm cov neeg npaj muaj ib tug tsawg sampling probability tshaj lwm tus
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