## The Sample Mean - Mathematical Sciences

**Post Hoc Tests in Analysis of Variance**

Here are the three average starting salaries for the three groups examined inthe previous analysis of variance (i.e., these are the three sample means):

Actually, if one subtracts the means from two samples, in most cases, there will be a difference. So the real question is not really whether the sample means are the same or different. The correct question is whether the population means are the same (i.e., are the two samples coming from the same or different populations)?

## Sample Means – Welcome | Department of Statistics

For example, suppose the random variable records a randomly selected student's score on a national test, where the population distribution for the score is normal with mean 70 andstandard deviation 5 (). Given a of 200 students, the distribution of the sample mean score has mean 70 and standard deviation 5/sqrt(200) = 5/14.14 = 0.35.

### Sample Mean -- from Wolfram MathWorld

**When the distribution of the population is normal, then the distributionof the sample mean is also normal. For a normal population distribution with mean and standard deviation , the distribution of the sample mean is normal, with mean and standard deviation .**

## Sample Word Meaning Questions - Available to Download

The from a group of observations is an estimateof the population mean . Givena sample of size , consider independent random variables , ,..., , each corresponding to one randomly selected observation. Each of these variables has the distribution of the population, with mean and standard deviation . The sample mean isdefined to be . **Sample Word Meaning Questions**

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