Hi
i am trying to use the formula for the position (or location) of a percentile in an array with n entries sorted in ascending order is:
Ly=(n+1)*y/100
I tried to use the formula for 10 observations to get 25% percentile (first quartile)
using the formula to define the L of 25% ==> (10+1)x25/100 = 2.75.
how come is that? shouldn’t be the location 2.5?