RESEARCH · METHODS · EVIDENCE
Choose a statistical method
Browse statistics lessons
- Statistics for research
- Center and spread
- Distributions and standard errors
- Statistical inference
- P-values and interpretation
- Critical values and test direction
- Compare means with t-tests
- Read t-test output
- Compare several means with ANOVA
- Read an ANOVA table
- Analyze categorical counts
- Read chi-square output
- Describe an association
- Read correlation results
- Interpret a regression model
- Choose a statistical method
- Statistics resources
| Question | Possible starting point | Check first |
|---|---|---|
| Two separate group means | Welch t-test | Independence and distributions |
| Matched mean difference | Paired t-test | Pairing and difference distribution |
| Several group means | ANOVA or an appropriate alternative | Variance model and planned comparisons |
| Categorical association | Chi-square or exact method | Counts, sparsity, independence |
| Numeric relationship | Correlation or regression | Functional form and measurement |
Ordinal outcomes, clustering, repeated measures, complex sampling, and missing data can require other methods. This table is an orientation, not an automatic decision rule.
References: NIST statistical handbook