Statistics and data analysis is an essential topic in science, but it is generally frustrating to navigate, and repeatedly misunderstood by scientists (even us!). There are many software packages out there; it can be hard to know what to put the effort into. It will often make sense to learn how to use packages that your institution has a subscription to (e.g. SPSS and MATLAB) but there are loads of other great software packages and programming language out there that are free to download and therefore very useful to learn (e.g. R and Python).
Laerd – A great how-to website for SPSS based statistics. The free guides usually aren’t enough alone, but your institute may have purchased the full guides (check with your library/statisticians) or you could combine this information with other tid-bits. -Still works
Discovering Statistics Using IBM SPSS Statistics – A statistics book worth buying. At first you will find his terrible jokes tiresome, but eventually they will come to comfort and amuse you as you navigate your way from introductory statistical concepts to advanced techniques. -Book still exists but this link is broken. New link
An R Tutorial – A basic introduction to using R. If you want a fun interactive introduction to R (that involves pirates!) try here. -Not sure if my computer just hates this or I cannot get this to work
Calvin College R – A list of commands used commonly in R, with some examples. -Still works
The Analysis Factor – A nice brief introduction to Factor Analysis. -Still works, also blog posts on various other things related to stats
Nature – Statistics for Biologists – A collection of articles discussing issues in biological statistics. You need some background knowledge before tackling these but they’re good discussions of issues in the area. -Still works