stat help

[G]

if you have a number that you know is the 50% percentile (say 50,000), and you don’t know the population size but you do know that it is a standard distribution – how would you calculate the 25 and 75 percentile.

[jdmXSI]

If you know what 50% is, wouldnt you +/- 25% to get what your looking for. Maybe i misunderstood the question, good luck though!

[benyl]

Originally posted by G
if you have a number that you know is the 50% percentile (say 50,000), and you don’t know the population size but you do know that it is a standard distribution – how would you calculate the 25 and 75 percentile.

You need to know the range in values.


50,000 can be the 50% percentile for a range of numbers from

0 to 100,000

or

49,000 to 51,000.

Both ranges can have a standard distribution.