Statistical Concepts

Statistical data used for prediction based on group-level data, often in risk assessment.

Actuarial Data

A statistical method used to compare means among three or more groups.

ANOVA (Analysis of Variance)

The weakening of the observed correlation due to measurement error.

Attenuation

Correlation of a variable with itself over successive time intervals, common in time-series data.

Autocorrelation

States that the sampling distribution of the mean approaches a normal distribution as the sample size increases.

Central Limit Theorem

A non-parametric test used to determine if a relationship exists between categorical variables.

Chi-Square

Indicates the proportion of variance in the dependent variable explained by the independent variable(s).

Coefficient of Determination (R²)

A range of values within which a population parameter is likely to fall with a certain level of confidence.

Confidence Interval

A statistical measure of the strength and direction of a linear relationship between two variables.

Correlation

A regression analysis used when the dependent variable is categorical (often binary).

Logistic Regression

A statistical technique that uses multiple predictors to estimate the value of a criterion variable.

Multiple Regression

A weighted average of variances from different groups, used in t-tests when variances are assumed equal.

Pooled Variance

The standard deviation of a sampling distribution, measuring the precision of a sample estimate.

Standard Error

Indicates how many standard deviations a score is from the mean.

Standard Score (Z-Score)

The probability that an observed effect is not due to chance (commonly p < .05).

Statistical Significance

A statistical test used to compare the means of two groups.

T-Test

A measure of how much scores differ from the mean.

Variance

The extent to which scores differ from each other and the mean (includes range, variance, standard deviation).

Variability