Qhov kev faib tawm ib txwm txhais tau li cas?
Qhov kev faib tawm ib txwm txhais tau li cas?

Video: Qhov kev faib tawm ib txwm txhais tau li cas?

Video: Qhov kev faib tawm ib txwm txhais tau li cas?
Video: txhais kev npau suav 2024, Kaum ib hlis
Anonim

ib txwm faib nkhaus . Hauv kev txheeb cais, theoretical nkhaus uas qhia tau hais tias ntau npaum li cas qhov kev sim yuav tsim ib qho txiaj ntsig. Cov nkhaus yog sib npaug thiab zoo li lub tswb, qhia tias kev sim siab feem ntau yuav muab cov txiaj ntsig ze qhov nruab nrab , tab sis qee zaus yuav deviate los ntawm ntau ntau. (Saib qhov tseem ceeb ntawm statistical.)

Ntxiv mus, hom kev faib tawm twg yog qhov nkhaus ib txwm?

Ib txwm faib yog symmetrical nyob ib ncig ntawm lawv txhais tau tias. Qhov nruab nrab, nruab nrab, thiab hom a kev faib khoom ib txwm muaj sib npaug. Thaj chaw hauv qab ib txwm nkhaus yog sib npaug li 1.0. Ib txwm faib yog denser nyob rau hauv nruab nrab thiab tsawg ntom nyob rau hauv lub tails.

Kuj Paub, dab tsi yog qhov nkhaus ib txwm nyob hauv kev txheeb cais? A ib txwm nkhaus yog lub tswb nrov nkhaus uas qhia qhov tshwm sim kev faib tawm ntawm ib tug nruam random variable. Ntxiv mus, lub ib txwm nkhaus sawv cev a kev faib khoom ib txwm muaj . Tsis tas li, tus qauv ib txwm nkhaus sawv cev a ib txwm nkhaus nrog txhais tau tias 0 thiab tus qauv sib txawv 1.

Tom qab ntawd, ib tug kuj yuav nug, dab tsi yog suav tias yog ib txwm faib?

Ib txwm faib , kuj hu ua Gaussian kev faib tawm , yog qhov tshwm sim kev faib tawm uas yog symmetrical txog qhov txhais tau tias, qhia tias cov ntaub ntawv nyob ze ntawm qhov txhais tau ntau zaus tshwm sim dua li cov ntaub ntawv nyob deb ntawm qhov nruab nrab. Hauv daim ntawv graph, kev faib khoom ib txwm muaj yuav tshwm raws li lub tswb nkhaus.

Qhov txhais tau li cas ntawm kev faib khoom sib xws?

Tus nqi xav tau (piv txwv li txhais tau tias) ntawm ib tug uniform random variable X yog: E(X) = (1/2) (a + b) Qhov no kuj tseem sau sib npaug li: E(X) = (b + a) / 2. "a" hauv cov qauv yog tus nqi tsawg kawg nkaus. hauv kev faib tawm , thiab "b" yog tus nqi siab tshaj plaws.

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