AP Stats Chapter 1 Vocabulary

Individuals

the objects described by a set of data. ______ may be people,

animals, or things.

Variables

any characteristic of an individual. A _____ can take different values for

different individuals.

Frequency Table

a ______ displays the counts (frequencies) of stations in

each format category.

Relative Frequency Table

a ________ shows the percents (relative frequencies) of stations in each format category.

Two-Way Table

a ______ describes two categorical variables

Marginal Distribution

The _________ of one of the categorical variables in a two-way table of

counts is the distribution of values of that variable among all individuals described by

the table.

Conditional Distribution

A _________ of a variable describes the values of that variable among

individuals who have a specific value of another variable. There is a separate

________ for each value of the other variable.

Segmented Bar Graph

in a _______ , for each category there is a single bar with

“segments” that correspond to the different individuals

Association

We say that there is an _______ between two variables if specific values of one

variable tend to occur in common with specific values of the other.

Mean “x-bar”

To find the ____ of a set of observations, add their values

and divide by the number of observations.

Median M

_________ is the midpoint of a distribution, the number such that half the observa-

tions are smaller and the other half are larger. To find the median of a distribution:

1. Arrange all observations in order of size, from smallest to largest.

2. If the number of observations n is odd, the median M is the center observation in

the ordered list.

3. If the number of observations n is even, the median M is the average of the two

center observations in the ordered list.

Interquartile Range

The _______ measures the range of the middle 50% of the data.

First Quartile

The _____ lies one-quarter of the

way up the list.

Third Quartile

The _____ lies three-quarters of the way up the list.

1.5 X IQR Rule for Outliers

Call an observation an outlier if it falls more than 1.5 × IQR above the third quartile or

below the first quartile.

Variance

______ is a numerical measurement that shows how far apart numbers in a data set are from their average (mean) value