二维随机变量(X,Y)的概率密度为f(x,y)=12yamp;#178;当二维随机变量(X,Y)的概率密度为f(x,y)=12yamp;#178;当0<y≤x<1时,f(x,y)=0,当其他时.求随机变量X,Y的相关系数ρxy
<p>问题:二维随机变量(X,Y)的概率密度为f(x,y)=12yamp;#178;当二维随机变量(X,Y)的概率密度为f(x,y)=12yamp;#178;当0<y≤x<1时,f(x,y)=0,当其他时.求随机变量X,Y的相关系数ρxy<p>答案:↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">李华欣的回答:<div class="content-b">网友采纳 Cov(X,Y)=E{}=E{XY-E(X)Y-E(Y)X+E(X)E(Y)}=E(XY)-E(X)E(Y)ρxy=Cov(X,Y)/[√D(X)√D(Y)]=/[√D(X)√D(Y)]E(X)=∫∫xf(x)dydx=4/5E(Y)=∫∫yf(x,y)dydx...
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