happytails.ai

Statistical test selection guide

Open Statistical test selection guide on Happytails.ai. This view has the same page content and links, with explicit tool capabilities. Read the processing notes before using a tool.

Tool capabilities

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Page guide

Answer a few questions about your question, outcome and groups to get a ranked list of suitable methods, the assumptions each one needs, and a link to the Happytails.ai tool that runs it.

How to use Statistical test selection guide
  1. Choose what you want to find out and the type of outcome.
  2. For comparisons, give the number of groups, pairing, the smallest group size and what you know about normality and spread.
  3. Run the guide and read the recommended method and the alternatives.
  4. Open the linked tool, or download the list.

Useful next steps

Correlation comparisonAgreement analysisSample size calculator

How suggestions are made

Fixed rules map your answers to methods. Comparisons of continuous outcomes suggest Welch's t test or Welch's ANOVA first; small groups with doubtful normality, ordinal outcomes and counts put rank tests first. Binary and category outcomes of independent groups suggest chi-square or Fisher's exact test. Paired yes/no data get McNemar's test for two measurements and Cochran's Q, run as the Friedman test on 0 and 1 codes, for three or more; one sample of yes/no outcomes gets the exact binomial test against a reference proportion. Paired category outcomes and one sample of categories are marked not suitable, because the Stuart-Maxwell, Bowker and goodness-of-fit tests they need are not available here. Other questions lead to regression, agreement, reliability, diagnostic accuracy, distribution, time series or meta-analysis tools.

Reading the list

Each candidate is marked recommended, alternative or not suitable, with fixed sentences for assumptions you have not confirmed, such as equal variances for Student's t test. Every suggestion links to the Happytails.ai page that runs it; a method marked not suitable links back to this guide.

Limits

The rules cover the methods in this catalogue only and cannot see your data or study design. They are a starting point to check with someone who knows the study, not a statistical review.