# Proper names for data - quantile and rank

Say I have data from a sample of 100 experiments. For a variable, I'm interested in showing the value x with 0.9 probability of non-exceedance, which is equivalent to P90 of the sorted sample.

I'm interested in proper names for these parameters:

x is a percentile, the 90-percentile to be specific, or more generally speaking, a quantile.

90 is the rank of x in my sample. Correct?

What would be the proper name for 0.9, or 90%? Also rank? Normalized rank? Strictly speaking it is the probability of non-exceedance, but writing that in a table header is not convenient :) A short but correct name for it would be very welcome.

• In ordinary usage 'parameter' refers to a population, not a sample. The word 'statistic' is more commonly used for samples. – BruceET Jul 25 '18 at 16:46