Choosing a statistical test
There are very many statistical tests available to the researcher. Which test one employs depends on several factors, for example:
O the purpose of the analysis (e.g. to describe or explore data, to test a hypothesis, to seek correlations, to identify the effects of one or more independent variables on a dependent variable, to identify differences between two or more groups; to look for underlying groupings of data, to report effect sizes)
O the kinds of data with which one is working (parametric and non-parametric)
O the scales of data being used (nominal, ordinal, interval, ratio)
O the number of groups in the sample O the assumptions in the tests O whether the samples are independent of each
other or related to each other.