learn.howToCalculate
learn.whatIsHeading
The paired t-test compares means of two related groups (e.g., before and after measurements on the same subjects). It tests whether the mean difference is significantly different from zero.
Formule
t = (d̄ − μ₀) / (sₐ / √n) where d̄ is mean difference, sₐ is std of differences
- d
- difference between paired measurements
- d̄
- mean of differences
- sₐ
- standard deviation of differences
- n
- number of pairs
- t
- t-statistic
Stapsgewijze handleiding
- 1Calculate differences d = before − after
- 2Mean difference d̄ and standard deviation s_d
- 3t = d̄ / (s_d/√n)
- 4Compare t to critical value for df = n−1
Uitgewerkte voorbeelden
Invoer
Before: [20,22,19], After: [18,20,18]
Resultaat
Mean diff = 1.67, t = 1.53, df = 2, not significant
Veelgestelde vragen
When do I use paired t-test vs. independent t-test?
Paired: same subjects measured twice (before/after). Independent: different subjects in two groups.
What is the null hypothesis for paired t-test?
H₀: mean difference = 0 (no difference between paired measurements).
Is paired t-test more powerful than independent t-test?
Yes, because pairing reduces variability (within-subject variation less than between-subject).
Klaar om te berekenen? Probeer de gratis Paired t-Test-rekenmachine
Probeer het zelf →