Use Z-test when population deviation (σ) is known and n > 30. Use T-test when σ is unknown (using sample s instead) or n < 30.

What is 'Degrees of Freedom'?

Degrees of freedom (df) generally equals n - 1 for a one-sample t-test. It relates to the number of independent values that can vary in the analysis.

Assumptions of T-test?

Data should be continuous, independent, and approximately normally distributed (especially for small samples).

Perform a one-sample Student's t-test (unknown population σ).

Sample Mean (x̄)

Population Mean (μ)

Hypothesized mean

Sample SD (s)

Standard deviation of the sample

Sample Size (n)

Significance Level (α)

t-Statistic

df = 0, p-value = 0

Since p >= 0.05, we fail to reject the null hypothesis.

Two-Tailed P-Value

One-Tailed P-Value

Documentation

t Statistic

Deg. Freedom

Frequently Asked Questions

How to Use

What it calculates

This t-test solves mathematical and statistical problems using standard formulas. Perform one-sample T-test for unknown population SD.

When to use it

Use for homework, data analysis, exam prep, or quick verification of manual calculations.

Example

Adjust the inputs above to model your specific scenario with the T-Test.

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