See also anova_welch anova_snk anova_scheffe 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_gameshowell(A, B, C, D, 0.05)

ANOVA Games-Howell 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  |    Std. Error    |   Sig   |    lower bound   |   upper bound    |

+-------+------------------+------------------+---------+------------------+------------------+

|  1  2 |          1.17500 |          0.42461 | 0.12436 |         -0.35533 |          2.70533 |

|  1  3 |         -0.30833 |          0.45266 | 0.90080 |         -1.84803 |          1.23137 |

|  1  4 |         -1.24500 |          0.57157 | 0.21910 |         -3.14022 |          0.65022 |

|  2  3 |         -1.48333 |          0.36140 | 0.01181 |         -2.61301 |         -0.35366 |

|  2  4 |         -2.42000 |          0.50239 | 0.01174 |         -4.16054 |         -0.67946 |

|  3  4 |         -0.93667 |          0.52632 | 0.35703 |         -2.68673 |          0.81339 |

+-------+------------------+------------------+---------+------------------+------------------+