analysis An explanation of the nature, meaning, or component parts of something.
arithmetic mean The average obtained by adding together all the values gathered and dividing the resulting sum by the number of cases.
average deviation A measure of variability obtained by subtracting each score from the mean score and averaging the deviations.
census The official process of counting the number of people in a country, city, or town and collecting information about them.
correlation The degree of association between two random variables.
data Facts or information used usually to calculate, analyze, or plan something. The singular of data is datum.
frequency The number of times that something happens during a particular period.
infinite Having no limits; extremely vast.
interquartile range A series of values that includes the middle 50 percent of cases.
median A value such that half of a series of scores arranged in order of magnitude are greater than the value and half are less than the value.
mode The value that occurs with the greatest frequency.
negative correlation Higher scores for one variable being associated with lower scores for another variable.
percentile rank A number between 0 and 100 that indicates the percent of cases falling at or below that score.
population A group of individual persons, objects, or items from which samples are taken for statistical measurement.
positive correlation Higher scores for one variable being associated with higher scores for another variable.
range A series of numbers that includes the highest and lowest possible amounts.
standard deviation A measure of variability obtained by squaring the deviations from the mean, adding them up, dividing by the number of cases, and finding the square root of that.
statistician A person who collects and studies statistics.
tabulation Arranging information in an organized way so that it can be studied, recorded, or so forth.
variability A measure of the spread of a data set.