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Calculate The T Statistic

T-Statistic Formula:

\[ t = \frac{\text{Mean}_1 - \text{Mean}_2}{\sqrt{\frac{s_1^2}{n_1} + \frac{s_2^2}{n_2}}} \]

value
value
std dev
std dev
size
size

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1. What Is The T-Statistic?

The t-statistic is a measure used in hypothesis testing to determine if there is a significant difference between the means of two groups. It follows a t-distribution under the null hypothesis and helps assess whether observed differences are statistically significant.

2. How Does The Calculator Work?

The calculator uses the t-statistic formula for two independent samples:

\[ t = \frac{\text{Mean}_1 - \text{Mean}_2}{\sqrt{\frac{s_1^2}{n_1} + \frac{s_2^2}{n_2}}} \]

Where:

Explanation: The t-statistic quantifies the difference between group means relative to the variation in the sample data. A larger absolute t-value indicates a greater difference between groups.

3. Importance Of T-Statistic Calculation

Details: Calculating the t-statistic is essential for conducting t-tests, which are fundamental in statistical analysis for comparing means between two groups. It helps researchers determine if observed differences are likely due to chance or represent true effects.

4. Using The Calculator

Tips: Enter the means, standard deviations, and sample sizes for both groups. All values must be valid (standard deviations ≥ 0, sample sizes > 0). The calculator will compute the t-statistic, which is unitless.

5. Frequently Asked Questions (FAQ)

Q1: When should I use a t-test?
A: Use a t-test when comparing the means of two independent groups, assuming approximately normal distributions and similar variances between groups.

Q2: What does the t-value indicate?
A: The t-value indicates the size of the difference relative to the variation in your sample data. Larger absolute t-values generally indicate stronger evidence against the null hypothesis.

Q3: How is the t-statistic related to the p-value?
A: The t-statistic is used to calculate the p-value. The p-value represents the probability of obtaining results at least as extreme as the observed results, assuming the null hypothesis is true.

Q4: What are the assumptions of the t-test?
A: The main assumptions include: independence of observations, approximately normal distribution of data, and homogeneity of variances between groups.

Q5: When should I use a paired t-test instead?
A: Use a paired t-test when measurements are taken from the same subjects at different times or under different conditions, as it accounts for the correlation between paired observations.

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