p-value · normal & Student t
p-value · normal & Student t: use test statistic, null distribution, degrees of freedom (t only). Review the formula, worked example and calculation steps.
Inputs
Use the units shown—
Enter your values and select Calculate.
Formula & explanation
One-sided tail under the selected null distribution; two-sided p = 2 × smaller tail.
Variables & units
- Test statistic
- Numeric value · minimum -1000000000000, maximum 1000000000000
- Null distribution
- Select an option
- Degrees of freedom (t only)
- Numeric value · minimum 0.000001, maximum 1000000000000
- Alternative
- Select an option
Worked example
Student t=1 with 1 degree of freedom gives two-sided p=0.5.
Assumptions
Requires a valid test statistic and null model; not the probability that a hypothesis is true. Does not implement F or chi-square tails.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
Use the default input values to find the answer. The reset icon restores those values.
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