When to use standard deviation/standard error
Posted 07 March 2012 - 11:17 PM
From what I understand, standard deviation gives you the variability within a group; standard error shows the error of a particular mean. But n=? for you to use each test?
Posted 10 March 2012 - 01:19 PM
Posted 11 March 2012 - 07:57 AM
Because you have to repeat your experiment several times independently, standard errors are okay in many cases. If you are unsure you can use also confidence intervals (typically 95%).
But this are not statistical tests, but descriptive statistics. In order to know which test to use they won't help you. You have to find out if the assumptions of the particular test is fulfilled (type of data, type of distribution, variance homogeneity, etc).
Edited by hobglobin, 11 March 2012 - 08:26 AM.
One must presume that long and short arguments contribute to the same end. - Epicurus
...except casandra's that belong to the funniest, most interesting and imaginative (or over-imaginative?) ones, I suppose.
Posted 12 March 2012 - 10:02 AM