Contents
Can a test be a test of the difference in medians?
Only if we are prepared to make the additional assumption that the difference in the two groups is simply a shift in location (that is, the distribution of the data in one group is simply shifted by a fixed amount from the other) can we say that the test is a test of the difference in medians.
How to compare two groups for statistical differences?
In the final part of the article, a test selection algorithm will be proposed, based on a proper statistical decision-tree for the statistical comparison of one, two or more groups, for the purpose of demonstrating the practical application of the fundamental concepts.
Which is the most common method of statistical inference?
Statistical hypothesis testing – last but not least, probably the most common way to do statistical inference is to use a statistical hypothesis testing. This is a method of making statistical decisions using experimental data and these decisions are almost always made using so-called “null-hypothesis” tests.
Is the Mann Whitney U test the same as independent samples?
This would be more in keeping with the Mann-Whitney U test being used as an alternative to the independent-samples t-test (i.e., both would then use a measure of central tendency: the ‘mean’ for the independent-samples t-test and the ‘median’ for the Mann-Whitney U test).
Which is the best tool for comparing two groups?
A common problem that arises in research is the comparison of the central tendency of one group to a value, or to another group or groups. Common statistical tools for assessing these comparisons are t-tests, analysis-of-variance, and general linear models.
How is the difference between two means calculated?
A confidence interval for the difference between two means specifies a \r range of values within which the difference between the means of the \r two populations may lie. These intervals may be calculated by, for example, \r a producer who wishes to estimate the difference in mean daily output \r from two machines;