HIT Chapter 10

Variable

A characteristic or property that may take on different values.

Normal Distribution of Data

A continuous frequency distribution characterized by a bell-shaped curve; that is, the mean, median, and mode are equal and most of the measurements are near the center of frequency.

Variance

A disagreement between two parts; the square of the standard deviation.

Graph

A graphic tool used to show numerical data in a pictorial representation.

Mode

A measure of central tendency that consists of the most frequent observation in a frequency distribution.

Mean

A measure of central tendency that is determined by calculating the arithmetic average of the observations in a frequency distribution.

Median

A measure of central tendency that shows the midpoint of a frequency distribution when the observations have been arranged in order from lowest to highest.

Standard Deviation

A measure or variability that describes the deviation from the mean of a frequency distribution in the original units of measurement; the square root of the variance.

Frequency Distribution

A table or graph that displays the number of times (frequency) a particular observation occurs.

Outlier

An extreme statistical value that falls outside the normal range.

Range

Distance of extent between possible extremes.

Descriptive Statistics

Statistics that describe population.

Variability

The difference between each score and every other score in a frequency distribution.

Quartile

The fourth part of an equal distribution.

Skewness

The horizontal stretching of a frequency distribution to one side or the other so that one tail is longer than the other.

Measurements

The systematic process of data collection, repeated over time or at a single point in time.

Decile

The tenth equal part of a distribution.

Measures of Central Tendency

The typical or average numbers that are descriptive of the entire collection of data for a specific population.