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median(y)=F^{-1}(1/2) if P(X>a)<1/2
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2Â¥2014-05-20 06:44:07
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statwh

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Var(y)=E(x^2)P(x>a)+a^2P(x<a)-(E(x)P(x>a)+aP(x<a))^2
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3Â¥2014-05-20 06:48:47
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shy1992331

гæ (СÓÐÃûÆø)

ÒýÓûØÌû:
3Â¥: Originally posted by statwh at 2014-05-20 06:48:47
Var(y)=E(x^2)P(x>a)+a^2P(x<a)-(E(x)P(x>a)+aP(x<a))^2
<Var(x)

Ó¦¸ÃÊÇVar(y)=E(x^2)P(x<a)+a^2P(x>a)-(E(x)P(x<a)+aP(x>a))^2°É£¿µ«ÊÇÓÉÕâ¸ö±í´ïʽµÃµ½Var(y)<Var(x)¸Ð¾õÒ²²»ÊÇÄÇô¼òµ¥
5Â¥2014-05-22 12:18:54
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shy1992331

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ÒýÓûØÌû:
4Â¥: Originally posted by ´øÇÊСµ¶ at 2014-05-20 11:31:42
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Var(y)=E(x^2)P(x<a)+a^2P(x>a)-(E(x)P(x<a)+aP(x>a))^2°É£¿µ«ÊÇÓÉÕâ¸ö±í´ïʽµÃµ½Var(y)<Var(x)¸Ð¾õÒ²²»ÊÇÄÇô¼òµ¥
6Â¥2014-05-22 12:19:02
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