# Manuals/calci/MANNWHITNEYUTEST

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**MANNWHITNEYUTEST (XRange,YRange,ConfidenceLevel,NewTableFlag)**

- is the array of x values.
- is the array of y values.
- is the value between 0 and 1.
- is either TRUE or FALSE.

## Description

- This function gives the test statistic value of the Mann Whitey U test.
- It is one type of Non parametric test.It is also called Mann–Whitney–Wilcoxon,Wilcoxon rank-sum test or Wilcoxon–Mann–Whitney test.
- Using this test we can analyze rank-ordered data.
- This test is alternative to the independent-sample, Student t test, and yields results identical to those obtained from the Wilcoxon Two Independent Samples Test.
- This test is used to compare differences between two independent groups when the dependent variable is either ordinal or continuous, but not normally distributed.
- Mann whitey u test is having the following properties:
- 1.Data points should be independent from each other.
- 2.Data do not have to be normal and variances do not have to be equal.
- 3.All individuals must be selected at random from the population.
- 4.All individuals must have equal chance of being selected.
- 5.Sample sizes should be as equal as possible but for some differences are allowed.
- Suppose the two groups of the populations have distributions with the same shape it can be viewed as a comparison of two medians.With out the assumption the Mann-Whitney test does not compare medians.
- To find statistic value of this test the steps are required:
- 1.For the two observations of values, find the rank all together.
- 2.Add up all the ranks in a first observation.
- 3.Add up all the ranks in a second group.
- 4.Select the larger rank.
- 5.Calculate the number of participants,number of people in each group.
- 6.Calculate the test statistic:

- where and are number of participants and number of people.
- is the larger rank total. is the similar value of .
- 7.State Result: In this step we have to take a decision of null hypothesis either accept or reject depending on the z value using critical value table.
- 8.State Conclusion: To be significant, our obtained U has to be equal to or LESS than this critical value.

## Example

X | Y |

87 | 71 |

72 | 42 |

94 | 69 |

49 | 97 |

56 | 78 |

88 | 84 |

74 | 57 |

61 | 64 |

80 | 78 |

52 | 73 |

75 | 85 |

0 | 91 |

- =MANNWHITNEYUTEST(A1:A12,B1:B12,0.05,true)

**Mann Whitney U Test**

x | y |
---|---|

20 | 10 |

11 | 2 |

23 | 9 |

3 | 24 |

5 | 15.5 |

21 | 18 |

13 | 6 |

7 | 8 |

17 | 15.5 |

4 | 12 |

14 | 19 |

1 | 22 |

Ranks | 139 | 161 |

Median | 73 | 75.5 |

n | 12 | 12 |

U1 | 83 |

U2 | 61 |

U | 61 |

E(U1) | 150 |

E(U2) | 150 |

E(U) | 72 |

StDdev | 17.320508075688775 |

0.05 | |

z | -0.6350852961085883 |

p | 0.5253738185447192 |

## Related Videos

## See Also

## References