If two random samples of sizes 30 and 45 are selected independently from two non-normal populations with means of 53 and 57, then the mean of the sampling distribution of the sample mean difference, $\bar { X } _ { 1 } - \bar { X } _ { 2 }$ , equals -4.

Question

Quizplus · Accepted Answer

The mean of the sampling distribution of the difference between two independent sample means, $\bar { X } _ { 1 } - \bar { X } _ { 2 }$, is equal to the difference between the population means, $\mu_1 - \mu_2$, which in this case is $53 - 57 = -4$.

If Two Random Samples of Sizes 30 and 45 Are Xˉ1−Xˉ2\bar { X } _ { 1 } - \bar { X } _ { 2 }Xˉ1​−Xˉ2​

If Two Random Samples of Sizes 30 and 45 Are $\bar { X } _ { 1 } - \bar { X } _ { 2 }$