14.5 Descriptive Statistics (Numerically)

Individuals

The things that a data set describes

Variable

The property of individuals that is described by the data

One-variable data

Only one property of each individual is measured

Summary statistic

A singular number that summarizes some property of the data

Measure of central tendency

The center of the data, mean, median, or mode

Mean

The sum of the individuals divided by the number of individuals

Median

The middle number or the average of the middle numbers

Outlier

A number in a data set that is far away from the rest of the data

Mode

The element that appears most often in the data

Bimodial

Has 2 modes

Frequency table

A(n) _______ for a set of data is a table that includes each different data point and the number of times a point occurs in the data

Stem-plot

A(n) ________ organizes data by using the digits of the numbers in the data

Measures of spread

Describe the spread or variability of the data around a central value

Standard deviation

In statistics, the ________ is a measure of the amount of variation or dispersion of a set of values.

Variance

The square of the standard variation

Minimum

The smallest possible quantity

Maximum

The largest possible quantity

First quartile

The median of the lower half of the data

Third quartile

The median of the upper half of the data

Five-number summary

Minimum, first quartile, median, third quartile, maximum

Range

Maximum-minimum

Interquartile range

IQR, third quartile - first quartile

Box plot

A method of graphically displaying a five number summary