当df=15时,查t分布表得两尾概率等于0.01的临界t值为t0.01(15) =2.947,其意义是:
A: P(-∞<t<-2.947)=
P(2.947<t<+∞)=0.99
B: P(-∞<t<-2.947)+
(2.947<t<+∞)=0.01
C: P(-∞<t<-2.947)=
P(2.947<t<+∞)=0.01
D: P(-2.947<t<2.947)=0.01
A: P(-∞<t<-2.947)=
P(2.947<t<+∞)=0.99
B: P(-∞<t<-2.947)+
(2.947<t<+∞)=0.01
C: P(-∞<t<-2.947)=
P(2.947<t<+∞)=0.01
D: P(-2.947<t<2.947)=0.01
举一反三
- 当df=15时,查t分布表得两尾概率等于0.01的临界t值为t0.01(15) =2.947,其意义是: A: P(-∞<;t<;-2.947)+ (2.947<;t<;+∞)=0.01 B: P(-∞<;t<;-2.947)= P(2.947<;t<;+∞)=0.99 C: P(-∞<;t<;-2.947)= P(2.947<;t<;+∞)=0.01 D: P(-2.947<;t<;2.947)=0.01
- 逻辑判断式中错误的是________。 A: t > 20 B: t>=1 && t<=3 C: t >= 1 And t <= 3 D: t<=1 || t >=3
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