Statistics Chapter 2

Front 1

Representative Value

Back 1

An efficient way to describe a group of scores

Front 2

Variability

Back 2

The amount of variation among scores

Front 3

Central Tendency

Back 3

The middle of the group of scores

Front 4

Mean

Back 4

The average-the sum of all the scores divided by the number of scores
-Add up all of the scores, then divide this sum by the number of scores

Front 5

Mode

Back 5

-The most common single value in a distribution
-usually used for describing the central tendency for a nominal variable

Front 6

Median

Back 6

The middle score, or with an even number of scores, the mean for the two middle scores
-Line up all the scores from lowest to highest, figure out how many scores there are to the middle score by adding 1 to the number of scores and dividing by 2, count up to the middle score or scores

Front 7

Outlier

Back 7

An extreme score

Front 8

Variance

Back 8

How spread out the scores are around the mean, the average of each score's squared difference from the mean.

Front 9

Deviation Score

Back 9

How far away the score is from the mean

Front 10

Standard Deviation

Back 10

The way to describe the spread of a group of scores
-Figure the variance, take the square root: it is the positive square root
-It is the average amount that scores differ from the mean

Front 11

Computational Formula

Back 11

A shortcut to simplify the figuring of variance and standard deviation

Front 12

Definitional Formula

Back 12

Formulas that reinforce the underlying principles