在用Matlab繪制各種常用概率分布的密度函數時，都比較簡單，唯獨超幾何分布試了幾次都不成功，輸出結果總是 C]H'z  
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        查看了一下幫助  help hygepdf 4'EC(NR7N  
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HYGEPDF Hypergeometric probability density function. a2Q_K2t  
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    Y = HYGEPDF(X,M,K,N) returns the hypergeometric probability e+416 ~X v  
    density function at X with integer parameters M, K, and N. F&pJ faig  
    Note: The density function is zero unless X is an integer. NABVU0}
 
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    The size of Y is the common size of the input arguments. A scalar input   CjeAO 2  
    functions as a constant matrix of the same size as the other inputs.     =VXxQ\{  
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    See also hygecdf, hygeinv, hygernd, hygestat, pdf. fu 0]BdM  
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    Reference page in Help browser .zDm{_'  
       doc hygepdf +E5EOo{ `|  
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        超幾何分布參數較多，這里關于三個參數的指代不詳。又在互聯網上查了相關資料，包括該函數的定義式： lJ y\Ky(*  
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                   http://ccpublic-1.central.cranfield.ac.uk/2001DMSOMFRC/pr062320/Matlab/stats/hygepdf.m )GgO=J:o  
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        直到發(fā)現這個例子后才清楚各個參數所代表的具體意義。 WBOe
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Suppose you have a lot of 100 floppy disks and you know that 20 of them are defective. What is the probability of drawing 0 through 5 defective floppy disks if you select 10 at random? EGD&/%aC  
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p = hygepdf(0:5,100,20,10) CEOD$nYc  
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p =  0.0951 0.2679 0.3182 0.2092 0.0841 0.0215 JIJ79HB  
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詳細可參見： BZUA/;Hz &  
http://www.physnet.uni-hamburg.de/physnet/matlab/help/toolbox/stats/hygepdf.html#4257 `-,y
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        果然與一般對超幾何分布公式字母慣常表示方式有所不同。嘗試將上述分布作圖如下 LA\)B"{J  
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x = 0:5