anova_snk(A, B, C,..., alpha)
Student-Newman-Keuls test for k means using significance level alpha.
See also anova_welch anova_bonferroni anova_lsd anova_duncan
Example
A=(14.5, 13.4, 14.1, 15.1)
( 14.5 13.4 14.1 15.1 )
B=(13.2, 12.7, 12.6, 13.9, 13.1)
( 13.2 12.7 12.6 13.9 13.1 )
C=(14.8, 15.2, 14.4, 13.3, 15, 14.8)
( 14.8 15.2 14.4 13.3 15 14.8 )
D=(16.1, 16.2, 14.7, 16.4, 14.2)
( 16.1 16.2 14.7 16.4 14.2 )
anova_snk(A, B, C, D, 0.05)
ANOVA SNK multiple comparison test
Confidence interval for the difference of k population means.
Independent and samples. Normal populations with equal std.
Number of populations k: 4
Confidence level : 0.05 (5.0%)
Results:
+-------+------------------+----+------------------+---------+-------------------------------------+
| | | | | | 95% Confidence interval |
| | | | | +------------------+------------------+
| | Mean difference | p | Std. Error | Sig | lower bound | upper bound |
+-------+------------------+----+------------------+---------+------------------+------------------+
| 1 2 | 1.17500 | 2 | 0.33707 | 0.02542 | 0.16440 | 2.18560 |
| 1 3 | -0.30833 | 2 | 0.33707 | 0.52693 | -1.31893 | 0.70227 |
| 1 4 | -1.24500 | 3 | 0.33707 | 0.04707 | -2.47506 | -0.01494 |
| 2 3 | -1.48333 | 3 | 0.33707 | 0.01745 | -2.71339 | -0.25328 |
| 2 4 | -2.42000 | 4 | 0.33707 | 0.00060 | -3.78388 | -1.05612 |
| 3 4 | -0.93667 | 2 | 0.33707 | 0.06704 | -1.94727 | 0.07393 |
+-------+------------------+----+------------------+---------+------------------+------------------+
+-------+----------+------------------+
| Index | Variable | Mean |
+-------+----------+------------------+
| 2 | B | 13.10000 |
| 1 | A | 14.27500 |
| 3 | C | 14.58333 |
| 4 | D | 15.52000 |
+-------+----------+------------------+