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Statistics AI Solver with conditions checked

Confidence intervals, hypothesis tests, probability, distributions and regression — each answer says which method fits, checks its assumptions and explains what the result means.

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Result

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Ask a statistics question in four steps

  1. Give the data and the question

    Type the summary values or paste a small data set, or upload a photo of the problem up to 5 MB.

  2. Pick your level

    College / university is preselected; switch to high school for introductory probability, and choose an explanation style.

  3. Follow the method

    Read why a method fits, whether its conditions hold, and each formula with the numbers substituted.

  4. Interpret and practice

    The answer closes with what the number means in context, a way to verify it and a practice question; continue in AI Chat if you need more.

What a statistics answer includes

  • Sample or population?

    The answer starts by deciding which you have, because it changes the formula and the distribution you use.

  • Conditions spelled out

    Random sampling, independence, normality or a large enough sample — each condition is stated and checked.

  • Intermediate values

    Standard errors, test statistics and degrees of freedom appear on their own lines in math notation, not just the final number.

  • Plain-language meaning

    Results are explained in the words of your question, including what a p-value does not tell you.

Worked example: a 95% confidence interval for a mean

Take the sample from the example question: n = 40, x̄ = 72, s = 8. The population standard deviation is unknown, so the interval uses the t distribution with n − 1 = 39 degrees of freedom. With 40 observations, the sampling distribution of the mean is close to normal even if the scores are a little skewed.

The standard error is s ÷ √n = 8 ÷ √40 ≈ 1.265. The critical value t* for 95% confidence and 39 degrees of freedom is about 2.023, so the margin of error is 2.023 × 1.265 ≈ 2.56. The interval is 72 ± 2.56, or roughly 69.4 to 74.6.

Interpretation matters as much as arithmetic: we are 95% confident that the true mean score lies between about 69.4 and 74.6. The 95% describes the method — about 95 of every 100 intervals built this way would capture the true mean — not a 95% probability that this particular interval is right.

To double-check summary values such as the mean and standard deviation, the free statistics and standard deviation calculators run in your browser.

Common misreadings it helps you avoid

  • A p-value is not the chance the null is true

    It is the probability of data at least this extreme if the null hypothesis were true. It says nothing direct about how likely the hypothesis itself is.

  • Not rejecting is not proving

    Failing to reject the null means the evidence was not strong enough, not that the null is correct.

  • Correlation is not causation

    A strong r in an observational study does not show that one variable causes changes in the other.

  • Why divide by n − 1

    Dividing by n − 1 instead of n gives the sample variance, which estimates the population variance without bias; its square root is s.

Frequently asked questions

It works best with summary values or small data sets pasted as text. It cannot open a spreadsheet file, so compute the summaries first — the statistics calculator helps — and ask about the method.

It handles the usual intro and intermediate course material: z and t procedures, proportions, chi-square tests, ANOVA basics, correlation and linear regression, plus probability rules and the normal, binomial and Poisson distributions.

It cannot draw. It describes the shape — center, spread, skew, the shaded tail area — so you can sketch or plot it yourself.

Not on a Pro plan, where it is included* (*fair use: up to 300 runs a day across the writing, study and code tools). Without a plan, expect 2 credits per typed question and 3 if you add a photo. If you are signed out, the beginning of the answer is shown as a free preview.

That depends on your course. Study the worked method, compare it with your own solution, and stick to the rules your instructor sets for AI tools.

Yes — table lookups and rounding are common slip points. Recompute the key values and make sure the interpretation answers the question that was asked.

Number-crunching help

Not sure which test to use?

Get the method, its conditions and a plain-English interpretation, then try a similar problem.

Explain my statistics question
  • Conditions checked
  • Formulas before numbers
  • Results put in context