T-Test Calculator
Calculate the one-sample t-statistic. Compare a sample mean to a population mean using the t-test formula.
How to Use the T-Test Calculator
- Enter the sample mean, population mean, standard deviation, and sample size.
- Click Calculate to compute the t-statistic.
- Compare with the critical value to assess significance.
Referência Rápida
| De | Para |
|---|---|
| df=10, α=0.05 | t crit = 2.228 |
| df=20, α=0.05 | t crit = 2.086 |
| df=30, α=0.05 | t crit = 2.042 |
| df=∞, α=0.05 | t crit = 1.96 |
| |t| > crit | Reject H₀ |
Casos de Uso
- •Testing whether a drug treatment differs from a known baseline.
- •Comparing class performance to a national average.
- •Quality assurance checks against specification targets.
Fórmula
t = (x̄ − μ) / (s / √n). Degrees of freedom = n − 1. Standard error = s / √n.
Perguntas Frequentes
What is a t-test?
A statistical test that determines whether a sample mean significantly differs from a hypothesized population mean.
When should I use a t-test?
When the sample size is small (typically < 30) and the population standard deviation is unknown.
How do I interpret the t-statistic?
Compare |t| with the critical t-value for your df and significance level. If |t| > critical, the difference is significant.