Flashcards in Chapters 7 and 8 Test 3 Review Deck (17)

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1

## If alpha is known, what are the assumptions that come with it?

###
That it is a simple random mean.

It is a normal population or a large sample size.

2

## What is a sample error?

### It is the error that can occur from using a sample to estimate a population's characteristics.

3

## What does the term "bar x" signify?

### Sample mean

4

## What does "sample distribution of a sample mean" mean?

### It is the distribution of all possible sample means of sample size (bar x).

5

## What does the xi stand for in the equation for the population standard deviation?

### each of the numbers in the sample size

6

## What does the "u" represent in the equation for the population standard deviation?

### the mean of the population

7

## What does the "N" stand for in the equation for the population standard deviation?

### the size of the population

8

## How do we find the standard deviation of the means of little samples of a population?

### by using the formula for standard deviation

9

## What is the central limit theorem?

### For a relatively large sample size, the variable bar x is approximately normally distributed, regardless of the distribution of the variable under consideration.Increased sample sized makes this even better.

10

## What is considered a large sample space?

### 30

11

## How do you find the standard deviation of bar x?

### standard deviation (of bar x)= standard deviation/ square root of n

12

## What is the formula for finding the sampling distribution of a sample mean?

###
For the mean: (ux=u) the mean of the population is equal to the mean of the sample size

For the standard deviation: sigma (x)= sigma/ square root of n

13

## Approximately 68% of all possible samples have means that lie within what of the population u?

### sigma over square root of n

14

## Approximately 95% of all possible samples have means that lie within what of the population u?

### 2 sigmas over the square root of n

15

## Approximately 99/7% of all possible samples have means that lie within what of the population u?

### 3 sigmas over the square root of n

16

## Approximately 100% percent of all possible samples have means within what of the population mean.

### z alpha over 2

17