Flashcards in Chap 6 Standard Errors Deck (11):

1

## Central Limit Theorem

### The fact that as a sample size increases, the sample distribution of the mean becomes increasingly normal, regardless of the shape of the distribution of the sample.

2

## Degrees of Freedom

### Roughly the minimum amount of data needed to calculate a statistic. More practically, it is a number or numbers, used to approximate the number of observations in the data set for the purpose of determining statistical significance.

3

## Expected Value of the Mean

###
The value of the mean one would expect to get from a random sample selected from a population with a known mean.

i.e. if one knows the population has a mean of 5 on some variable, one would expect a random sample selected from the population will also have a mean of 5.

4

## Inferential Statistics

### Statistics generated from sample data that are used to make inferences about the characteristics of the population the sample is alleged to represent.

5

## Sampling Distribution of the Differences b/w the Means

### The distribution of scores that would be generated if one were repeatedly draw two random samples of a given size from a 2 populations and calculate the difference b/w the sample means

6

## Sampling Distribution of the Mean

### The distribution of scores that would be generated if one were to repeatedly draw random samples of a given size from two population and calculate the mean for each sample drawn.

7

## Sampling Distribution

### A theoretical distribution of any statistic that one would get by repeatedly drawing random samples of a given size from the population & calculating the statistic of interest for each sample.

8

## Standard Error

### The standard deviation of a sampling distribution.

9

## Statistically Significant

###
A term indicating that a phenomenon observed in a sample( or samples) has meaningful implications for the population.

i.e. That the difference b/w a sample mean and a population mean is statistically significant or that a relationship observed b/w 2 variables in a sample is strong enough, relative to the standard error, to indicate a relationship b/w the 2 variables in the population from which the sample was selected.

10

## sx ̅

###
The standard error of the mean estimated from the sample standard deviation.

i.e. when a population standard deviation is unknown

11