Measures of Dispersion

These flashcards cover key concepts related to measures of dispersion, including definitions and explanations of range, standard deviation, variance, and more.

Measures of Dispersion

Descriptive statistical techniques used to identify individual differences in scores or values in a sample.

Standard Deviation (SD)

A measure of dispersion indicating the average number of points by which scores vary from the mean.

Variance

A measure of dispersion that is the square of the standard deviation, representing how data points differ from the mean.

Range

The difference between the highest and lowest values in a data set.

Difference Scores

Scores that indicate the deviation of each value from the mean, calculated by subtracting the mean from each value.

Mean Deviation

The average deviation of scores from the mean, calculated using absolute values of difference scores.

Standard Error (SE)

A measure indicating how much the sample mean is expected to vary from the true population mean.

Confidence Intervals

Ranges that estimate how closely the sample mean approximates the population mean, utilizing the standard error.

Degrees of Freedom (df)

The number of independent pieces of information free to vary, typically calculated as n − 1 in statistical analyses.

Normal Distribution

A probability distribution that is symmetric and bell-shaped, with most data points clustering around the mean.