When two independent random samples of sizes and have been selected from populations with means and , and variances and , which of the following is true?
A) The mean ofis.
B) The standard error ofis.
C) The standard error ofis estimated as.
D) All of these.
E) None of these.

Question

When two independent random samples of sizes  and  have been selected from populations with means  and  , and variances  and  , which of the following is true?
A) The mean ofis. 
B) The standard error ofis. 
C) The standard error ofis estimated as. 
D) All of these. 
E) None of these.

Quizplus · Accepted Answer

The mean of the difference between two independent samples can be calculated as:

µ1-µ2

The standard error of the difference between two independent samples can be estimated as:

√((s1^2/n1) + (s2^2/n2))

Therefore, both A and B are true. 
C is also true as it represents the formula for estimating the standard error. 
Thus, the correct choice is D, i.e., all of these are true.

When Two Independent Random Samples of Sizes and