Anonymous user
Welch's t-test: Difference between revisions
no edit summary
m (→{{header|C}}) |
No edit summary |
||
Line 8:
<math>t \quad = \quad {\; \overline{X}_1 - \overline{X}_2 \; \over \sqrt{ \; {s_1^2 \over N_1} \; + \; {s_2^2 \over N_2} \quad }} </math>
where
<math>\overline{X}_n </math> is the mean of set <math>n</math>,
and
<math>N_n</math> is the number of variables in set <math>n</math>,
and
<math>s_n </math> is the sample variance of set <math>n</math>, i.e.
<math>s_n = \sqrt{\frac{1}{N_n-1} \sum_{i=1}^{N_n} \left(X_i - \overline{X}_N\right)^2} </math>
and the degrees of freedom, <math>\nu</math> can be approximated:
| |||