Wednesday 16 September 2009

Really basic stats: what can we do with these variables?

Here is a quick guide for statistics that are ok to compute with kind of variable:

OK to compute.... Nominal Ordinal Interval Ratio
frequency distribution. Yes Yes Yes Yes
median and percentiles. No Yes Yes Yes
add or subtract. No No Yes Yes
mean, standard deviation, standard error of the mean. No No Yes Yes
ratio, or coefficient of variation. No No No Yes

Source: http://www.graphpad.com/faq/viewfaq.cfm?faq=1089