DRV Flashcards
1
Q
E(aX)
A
aE(X)
2
Q
Var(aX)
A
a^2Var(X)
3
Q
E(x+b)
A
E(X)+b
4
Q
Var(x+b)
A
Var(x)
5
Q
E(aX+b)
A
aE(X)+b
6
Q
Var(aX+b)
A
a^2Var(X)
7
Q
Mean/ E(X)
A
multiply the variable by the probablity and add all the values together Sigma x*P(X=x)
8
Q
variance
A
E(X^2)- Mean^2 (square the variable)
9
Q
if you know E(X) and Var(X) how can you work out E(S^2)
A
use the formula for Var(X): E(x^2)-E(X)^2
10
Q
E[f(X)+ g(X)]
A
E[f(x)] + E[g(x)]
11
Q
E[kg(X)]
A
kE[g(x)]
