【正确答案】
【答案解析】1-[1-F(x)]
n-1
;F(y);{1-[1-F(x)]
n-1
}F(y)
[解析] 根据简单随机样本各分量X
i
相互独立且与X同分布,有
Fx(x)=P{min(X
1
,X
2
,…,X
n-1
)≤x}
=1-P{min(X
1
,X
2
,…,X
n-1
)>x}
=1-P{X
1
>x,X
2
>x,…,X
n-1
>x)
=1-P{X
1
>x}P{X
2
>x)…P{X
n-1
>x}
=1-[1-P{X
1
≤x}][1-P{X
2
≤x}]…[1-P{X
n-1
≤x}]
=1-[1-F(x)]
n-1
.
FY(y)=P{X
n
≤y}=F(y)
G(x,y)=P{min(X
1
,…,X
n-1
)≤x,X
n
≤y}
=P{min(X
1
,…,X
n-1
)≤x}P{X
n
≤y}
={1-[1-F(x)]
n-1
}F(y).