troubleshooting Question

How many different colors in sample

Avatar of derduff
derduffFlag for Germany asked on
Math / Science
13 Comments1 Solution380 ViewsLast Modified:
Dear experts,

first of all I should point out, that this is not homework. I rephrased a problem I have at work in classical analogies of probability theory.

Suppose you have an urn with balls of different colors. There are n colors and k balls of each color. You draw m (m << n) balls. Lets say with replacement, but it is not really important.

Question: What is the probability that the sample contains balls of exactly c different colors (not matter which ones).

n = number of colors
k = number of balls for each color
m = number of balls drawn
c = number of different colors in the sample

Asked for:
Probability of c given n,k and m = P(c | n,k,m)

I am really looking for a closed form,like a formula/method which takes n,k,m and c.

I am not interested in specific examples like
Join our community to see this answer!
Unlock 1 Answer and 13 Comments.
Start Free Trial
Learn from the best

Network and collaborate with thousands of CTOs, CISOs, and IT Pros rooting for you and your success.

Andrew Hancock - VMware vExpert
See if this solution works for you by signing up for a 7 day free trial.
Unlock 1 Answer and 13 Comments.
Try for 7 days

”The time we save is the biggest benefit of E-E to our team. What could take multiple guys 2 hours or more each to find is accessed in around 15 minutes on Experts Exchange.

-Mike Kapnisakis, Warner Bros