Today’s post is about the difference between random error (http://en.wikipedia.org/wiki/Random_error) and systematic error (http://en.wikipedia.org/wiki/Systematic_error). Another analogy awaits you. (This blog could probably be entirely about errors.)
Imagine painting a wall. You finish your first coat of paint. Before passing out from the paint fumes, you notice that there are spots missing paint. Furthermore, you notice there seem to be two types of areas without paint.
