The variance of randomvariable of x then var(x) = E[x-E[x]2 = E[________]?

Related Mcqs:

1. If a & b are constants, then Var (a + bX) equal to_________________?

   A. Var(bX) + a
   B. b2 Var(X)
   C. b Var(x)
   D. None of these

2. For two independent random variables X & Y, Var (x ± y)=___________?

   A. Var(X) + Var (Y)
   B. Var(X) – Var (Y)
   C. Var (X)±
   D. Zero

3. Var (kY)= ____________?

   A. k Var (Y)
   B. k2 Var(Y)
   C. Var(Y)
   D. k2

4. If a and b are two constants, then Var(a+bX) is_______________?

   A. a±bVar(X)
   B. Var(a)±Var(X)
   C. ±bVar(X)
   D. b2Var(X)
   E. (a±b)Var(X)

5. Var(2X+3) is________________?

   A. 5 Var(X)
   B. 4 Var(X)
   C. 4 Var(X)+3
   D. 5 Var(X)+3

6. if Var(θˆ)→0 as n → 0, then θˆ is said to be______________?

   A. Sufficient
   B. Efficient
   C. Unbiased
   D. Consistent

7. if Var(T2)_______________?

   A. Efficient
   B. Sufficient
   C. Unbiased
   D. Consistent

8. Sample variance S2 is unbiased estimator of population variance 26 because ________________?

   A. E(S2) = s2
   B. E(u) = X
   C. E(P) = P
   D. Ux = u

9. suppose for 40 observation, the variance is 50. If all the observation are increased by 20, the variance of these increased observation will be_________?

   A. 50
   B. 70
   C. 50/20
   D. 50-20=30

10. The variance of 5 numbers is 10. If each number is divided by 2, then variance of new number is_____________?

    A. 20
    B. 5
    C. 2.5
    D. 0