Disclaimer

StatReason computes statistical results from the numbers you provide. It does not, and cannot, know anything about how those numbers were collected, whether the study behind them was designed appropriately, or what decision you intend to make with the result.

A correct calculation is not the same as a correct conclusion

A calculator can verify things like sample size, missing values, or an observed variance ratio directly from the numbers you enter. It cannot verify that your observations are independent, that your sampling or assignment process was sound, that what you measured is a valid measure of what you intended to study, or that a study design supports a causal claim. Where a page distinguishes "calculated from your data" from "you must verify," that distinction is the actual boundary of what a calculator can know.

Not professional or academic advice

Nothing on this site is statistical, scientific, medical, financial, legal, or academic advice, and it is not a substitute for consulting a qualified statistician, your instructor, an institutional review process, or a domain expert for a decision that actually matters. This is true regardless of how confident a specific result or interpretation reads.

No guarantee of fitness for a specific use

Calculations are provided for general informational and educational use. This site makes no warranty that a given engine is appropriate for your specific dataset, research question, regulatory context, or publication standard. You are responsible for confirming that the method you selected is the right one for your situation before relying on its result.

Effort toward correctness

Formulas and conventions are validated against documented sources and reference implementations before an engine ships (see Methodology). Even so, software can contain errors. If you find one, or a result that looks wrong, use the Contact page to report it.