What Is a T Distribution? The T distribution is a statistical distribution curve that looks almost identical to the normal statistical distribution curve. However, it is used instead when evaluating smaller samples. As a result, the T distribution tends to be shorter with fatter tails. The T distribution is frequently […]

# Statistics

What Is Stepwise Regression? Stepwise regression is a statistical technique for regressing several variables while concurrently deleting those that aren’t significant. The process uses a step-by-step iterative construction of a regression model. Independent variables are selected for use in a final model through a series of automated steps. At every […]

What Are Nonparametric Statistics? Nonparametric statistics is a statistical inference method focusing on rankings rather than numbers or underlying distribution assumptions. With nonparametric statistics, data are not expected to come from specified models determined by a small number of parameters. Examples of such models include the normal distribution model and […]

What Is a Discrete Probability Distribution? A discrete probability distribution describes the occurrence of a discrete random variable with a countable value and a non-zero probability. A discrete probability distribution displays the occurrence of discrete, individually countable events like 1, 2, 3,… or zero vs. one. For instance, the binomial […]

What Is Autocorrelation? Autocorrelation is a statistical representation of the degree of correlation between the same variables measured at successive time intervals. Correlation indicates the strength of a linear relationship between two variables. Whereas, autocorrelation measures the strength of a linear link between time series lagged values. It measures the […]

What Is the Empirical Rule? The Empirical Rule states that virtually all observed data for a normal distribution will fall within three standard deviations of the mean or average. The empirical rule is also known as the three-sigma rule or the 68-95-99.7 rule. It is a statistical axiom stating that […]