急求一道概率分布题答案已知二维随机变量(a,b)的概率分布为:\ Y 1 2X\1 1/2 1/42 1/4 0求:1) X,Y的边缘概率分布;2)期望EX和EY,方差DX和DY
来源:学生作业帮助网 编辑:作业帮 时间:2024/08/28 01:04:01
![急求一道概率分布题答案已知二维随机变量(a,b)的概率分布为:\ Y 1 2X\1 1/2 1/42 1/4 0求:1) X,Y的边缘概率分布;2)期望EX和EY,方差DX和DY](/uploads/image/z/13334583-39-3.jpg?t=%E6%80%A5%E6%B1%82%E4%B8%80%E9%81%93%E6%A6%82%E7%8E%87%E5%88%86%E5%B8%83%E9%A2%98%E7%AD%94%E6%A1%88%E5%B7%B2%E7%9F%A5%E4%BA%8C%E7%BB%B4%E9%9A%8F%E6%9C%BA%E5%8F%98%E9%87%8F%EF%BC%88a%2Cb%EF%BC%89%E7%9A%84%E6%A6%82%E7%8E%87%E5%88%86%E5%B8%83%E4%B8%BA%EF%BC%9A%5C+Y+1+2X%5C1+1%2F2+1%2F42+1%2F4+0%E6%B1%82%EF%BC%9A1%EF%BC%89+X%2CY%E7%9A%84%E8%BE%B9%E7%BC%98%E6%A6%82%E7%8E%87%E5%88%86%E5%B8%83%EF%BC%9B2%EF%BC%89%E6%9C%9F%E6%9C%9BEX%E5%92%8CEY%2C%E6%96%B9%E5%B7%AEDX%E5%92%8CDY)
x){ְƦ';^6N~y_ӎ;_.|g;n|'zrV9x~OGN=g k|c=b""bL( -J)DDط&3(lgsfF<lΧx.6IE]VEZ~ #b7`KP_v6C9N I==C==#OOXD
07(K \#llMZ]#ԊK!6Xfk$HBZ\"lajFhBuL
̀:
͠J#maFbWj_\g #
急求一道概率分布题答案已知二维随机变量(a,b)的概率分布为:\ Y 1 2X\1 1/2 1/42 1/4 0求:1) X,Y的边缘概率分布;2)期望EX和EY,方差DX和DY
急求一道概率分布题答案
已知二维随机变量(a,b)的概率分布为:
\ Y 1 2
X\
1 1/2 1/4
2 1/4 0
求:1) X,Y的边缘概率分布;2)期望EX和EY,方差DX和DY
急求一道概率分布题答案已知二维随机变量(a,b)的概率分布为:\ Y 1 2X\1 1/2 1/42 1/4 0求:1) X,Y的边缘概率分布;2)期望EX和EY,方差DX和DY
1) X,Y的边缘概率分布
X..1 ..2
..3/4.1/4
Y..1...2
..3/4.1/4
2)期望EX和EY,方差DX和DY
EX=3/4+2*1/4=5/4 EX²=3/4+2²*1/4=7/4
EY=3/4+2*1/4=5/4 EY²=3/4+2²*1/4=7/4
DX=EX²-(EX)²=7/4-25/16=3/16
DY=EY²-(EY)²=7/4-25/16=3/16