i have a histogram with the y-axis showing the proportion in percentage. That makes sense to me but now i have read that histograms can be normalized with the result that the area of the rectangles is 1.
Can someone explain me the idea,reason behind this? Many thanks!
Not all histograms are normalised.
For example, individuals by hair color:
This histogram is not normalised, because individuals in result set are relevant.
Compare with repairs by car make:
This histogram is normalised to 100% because individual number of repairs is irrelevant.