Stat chapter 2

a distribution that has two values that have the highest frequency of scores

a collection, or group, of scores from a sample on a single variable. Often, but not necessarily, these scores are arranged in order from smallest to largest.

The arithmetic average of a distribution of scores

Dividing a distribution of scores into two equal groups by using the median scores as the divider. Those scores above the median are the "high" group whereas those below the median are the "low" group.

The score in a distribution that marks the 50th percentile. This is the score at which 50% of the distribution falls below and 50% fall above.

The score in the distribution that occurs most frequently.

When a distribution of scores has two or more values that have a highest frequency of scores.

in a skewed distribution, when most of the scores are clustered at the higher end of the distribution with a few scores creating a tail at the higher end of the distribution

Extreme scores that are more than two standard deviations above or below the mean

In a skewed distribution, when most of the scores are clustered at the lower end of the distribution with a few scores creating a tail at the higher end of the distribution.

A value derived from the data collected from a population, or the value inferred to the population from a sample statistic

The group from which data are collected or a sample is selected. The population encompasses the entire group for which the data are alleged to apply.

An individual or group, selected from a population, from whom or which data are collected.

When a distribution of scores has a high number of scores clustered at one end of the distribution with relatively few scores spread out toward the other end of the distribution, forming a tail.

A value derived from the data collected from a sample.

the sum of; to sum

An individual score in a distribution

The sum of X; adding up all of the scores in a distribution.

the mean of a sample

The mean of a population

The number of cases, or scores, in a sample.

The number of cases, or scores, in a population

Symbol for the median