Normalisation is a type of biasing to the set of results, to achieve a range of standard results which are more acceptable. This sounds like "doctoring" results but let me explain a bit better - Say a class of kids sits a GCSE exam and averages below par (say for example this class was expected to get grade Cs and Bs based on previous results/work done, but for some unknown reason only came out with Ds)- the examiners would look into the factors behind the below par average, perhaps the teacher was substandard, or even replaced half way through the year, or perhaps the exam itself was unusually harder. Anyway the bottom line is that everyone agrees that the class should have been getting better results than this, and that the results were perhaps not accurate of the class's abilities, so they agree to increase each result by a set amount, so that the actual class average is closer to the expected average. Another example (as you mention) is the Olympics in qualifying times - to go to the olympics for a certain event you need to reach a minimum standard, say for example you have to be able to do the 100 metres in sub 11 seconds (i'm just hypothesising here, i don't know the real qual times). Now, athletes who attempt the qualifying by attending events held at high altitude, would have a harder time making the grade than events at low altitude, so the times have to be "Normalised" to account for this, and other factors which may affect the results (weather, time of year etc). Hope this is understandable!