Of n1 randomly selected male smokers, x1 smoked filter cigarettes, whereas of n2 randomly selected female smokers, x2 smoked filter cigarettes. let p1 and p2 denote the probabilities that a randomly selected male and female, respectively, smoke filter cigarettes. (a) show that (x1/n1) − (x2/n2) is an unbiased estimator for p1 − p2. [hint: e(xi)

See explanation below

Step-by-step explanation:

An Estimator is unbiased if E(X) = p where E(X) is the expected value of X.

Remember that the Expected value of X is calculated by multiplying each of the possible outcomes by the likelihood each outcome will occur and then summing all of those values.

In this case, we have that:

E(X1) = n1p1  (since we have n1 male smokers with each of them with probability p1 of smoking)

E(X2) = n2p2 (since we have n2 female smokers with each of them with probability p2 of smoking)

So we have to prove that (X1/n1) - (X2/n2) is an unbiased estimator for p1 - p2.

This means that we have to prove (by definition) that

E(x1/n1)- E(x2/n2) = p1 - p2

But we know that E(X1) = n1p1 and E(X2)=n2p2

Therefore E(x1/n1)- E(x2/n2) = p1 - p2

and ∴ (X1/n1) − (X2/n2) is an unbiased estimator for p1 − p2.

in 4 days he will run   12/14

step-by-step explanation:

connie < felicia < stew

step-by-step explanation:

stew:

we need to find the slope

m = (y2-y1)/ (x2-x1)

    = (2650-795)/(10-3)

    = 1855/7

265 words per minute

connie:

we need to find the slope

m = (y2-y1)/ (x2-x1)

we have two points (0,0) and (4,800)

m = (800-0)/(4-0)

  m = 800/4

    200 words per minute

felicia:

260 words per minute

200< 260 < 265

connie < felicia < stew