# Overview SPSS Nonparametric Tests

SPSS Strictly, most “nonparametric tests” in SPSS are distribution free tests. Oddly, these two concepts are entirely different but often used interchangeably. They're mostly used for variables that are not normally distributed in small samples.

Choosing **which nonparametric test to use** is easy when we divide them into three groups.

# One Sample

Nonparametric tests for one sample are used for **one variable** and **one group of cases**. They compare a sample outcome such as a proportion or frequency distribution to a hypothesized population outcome.

# Related Samples

Nonparametric tests for related samples are used for **multiple variables** and **one group of cases**. They basically test if variables in a sample are similar enough to assume they're similar in the population too.

# Independent Samples

Nonparametric tests for independent samples are used for **one variable** and **multiple groups of cases**. They basically test if groups of cases in a sample are similar enough to assume they're similar in the population too.

# One Sample

## SPSS Binomial Test

SPSS binomial test is used for testing whether a proportion from a single dichotomous variable is equal to a presumed population value. Read More

## SPSS Sign Test for One Median – Simple Example

SPSS sign test for one median the right way. Recode your outcome variable into values higher and lower than the hypothesized median and test if they're distribted 50/50 with a binomial test. Read More

# Independent Samples

## SPSS Kruskal-Wallis Test – Simple Tutorial with Example

SPSS Kruskal-Wallis test is a nonparametric alternative for a one-way ANOVA. This tutorial shows how to run it and when to use it. Read More

## SPSS Mann-Whitney Test – Simple Example

The Mann-Whitney test is an alternative for the independent samples t test when the assumptions required by the latter aren't met by the data. The most common scenario is testing a non normally distributed outcome variable in a small sample (say, n < 25). Read More

## SPSS Median Test for 2 Independent Medians

SPSS median test evaluates if two groups of respondents have equal population medians on some variable. This easy tutorial quickly walks you through. Read More

# Related Samples

## SPSS Wilcoxon Signed-Ranks Test – Simple Example

SPSS Wilcoxon Signed-Ranks test is used for comparing two metric variables measured on one group of cases. It's the nonparametric alternative for a paired-samples t-test when its assumptions aren't met. Read More

## SPSS Cochran Q Test

SPSS Cochran's Q test is a procedure for testing whether the proportions of 3 or more dichotomous variables are equal. These outcome variables have been measured on the same people or other statistical units. Read More

## SPSS Friedman Test – Simple Example

SPSS Friedman test compares the means of 3 or more variables measured on the same respondents. Like so, it is a nonparametric alternative for a repeated-measures ANOVA that's used when the latter’s assumptions aren't met. Read More

## SPSS McNemar Test

SPSS McNemar test is a procedure for testing whether the proportions of two dichotomous variables are equal. The two variables have been measured on the same cases. Read More

## SPSS Sign Test for Two Medians – Simple Example

SPSS sign test for two related medians tests if two variables measured in one group of people have equal population medians. Read More