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Confidence intervals & tests

Use a statistical test only when the data and assumptions match the method. The result helps assess evidence; it does not prove a hypothesis.

Find it

Data → table → Statistics & plots → Mean inference / Additional hypothesis tests

Additional hypothesis tests explain how table series are used and expose the test inputs.
Additional hypothesis tests explain how table series are used and expose the test inputs.Click to enlarge ↗

Try it step by step

  1. Choose the test that matches your research question and data type.
  2. Prepare the table series in the required order.
  3. Enter the hypothesized value, confidence level and alternative when offered.
  4. Calculate and read the statistic, p value, degrees of freedom, confidence interval, assumptions and warnings.

Options explained

One-sample / Welch t test
Compare a mean with a hypothesized value or compare two independent samples. For paired observations, calculate differences first.
Mean z test
Uses the first series and a known population standard deviation.
One / two-proportion z
Use 0/1 observations; the first series supplies the one-sample test, and the first two supply the two-sample test.
Chi-square goodness of fit
Use the first two series as observed and expected counts.
Chi-square independence
Uses count data arranged across all series as a contingency table.
One-way ANOVA
Uses all series as groups.
Alternative / confidence
Where supported, choose not equal, less than or greater than, and 90%, 95% or 99% confidence. Mean intervals shown by the t tool are two-sided.

Screenshot

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