The Shapiro-Wilk test examines if a variable is normally distributed in a population. This assumption is required by some statistical tests such as t-tests and ANOVA.

The SW-test is an alternative for the Kolmogorov-Smirnov test. This tutorial shows how to run and interpret it in SPSS.

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A binomial test examines if a population percentage is equal to *x*.

Example: is 45% of all Amsterdam citizens currently single? Or is it a different percentage?

This simple tutorial quickly walks you through the basics.

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This tutorial walks you through running and interpreting a binomial test in SPSS. With step-by-step example on downloadable practice data file.

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This z-test compares separate sample proportions to a hypothesized population proportion. This tool is freely downloadable and super easy to use.

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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.

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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).

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

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A z-test for 2 independent proportions examines if some event occurs equally often in 2 subpopulations.

Example: do equal percentages of male and female students answer some exam question correctly?

This tutorial covers examples, assumptions and formulas and presents a simple Excel tool for running z-tests the easy way.

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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.

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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.

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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.

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

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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.

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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.

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## THIS TUTORIAL HAS 7 COMMENTS:

## By Monalisa on September 21st, 2018

Great help!

## By Loo on September 24th, 2018

Hi Ruben, Post hoc test is available for chi square test of independence by using standard residual method, for example for a 3 by 3 chi square table. But, is it possible to do it for a 2 by 2 table?

## By Ruben Geert van den Berg on September 24th, 2018

Hi Loo!

Post hoc tests examine

whichproportions differ if the main chi-square independence test indicates that 2 variables are associated.For a 2 by 2 table, however, you're comparing only 2 proportions. So there's no question

whichproportions differ -there's only 2 of them.On top of that, a z-test for 2 independent proportions is preferred over the chi-square test here. The significance levels are identical but the z-test provides a confidence interval of the difference too -which is very informative. For some stupid reason, it's missing from SPSS but we built a simple tool for it.

You can also inspect the (Pearson) correlation between the 2 variables. For some dumb reason it's called a phi coefficient for 2 dichotomous variables but it's technically identical to a Pearson correlation.

Last, Bonferroni corrected pairwise z-tests for larger (2 by 3, 3 by 3...) tables are often preferred over the adjusted standardized residuals. You can request the latter by adding BPROP to the CELLS subcommand as in

CROSSTABS education BY marital_status

/CELLS COUNT COLUMN BPROP

/STATISTICS CHISQ PHI.

Note that these tests only compare column (not row!) proportions.

Hope that helps!

SPSS tutorials

## By Mohamed on November 10th, 2018

Hi there

What apout IRT in spss ver 15

Tell me

Thank you

## By Ruben Geert van den Berg on November 10th, 2018

Hi Mohamed!

What do you mean by "IRT"? Item Response Theory? Please clarify.

Thx!

SPSS tutorials