Random Number generator with skewness

Question

I'm looking for a way to generate a random number with:

A lower and upper boundary
An average not in the middle of the specified range
An adjustable standard deviation

In Java.

More specifically: I want to generate a long list of numbers with a minimum of 0, maximum of 40 and an average of +- 5, and i'd like to be able to adjust how far around the average the numbers are.

Yes? i'm asking if anyone knows how to do this? I've played around with Random, but this doesn't seem to do the job. — Wim Schmitz, Mar 14 '17 at 13:50
Good, you seems to have a complet requirement. But have you tried something ? We are not a free coding service. — AxelH, Mar 14 '17 at 13:50
Maybe something like [this](http://stackoverflow.com/questions/31754209/can-random-nextgaussian-sample-values-from-a-distribution-with-different-mean)? — npinti, Mar 14 '17 at 13:50
In fairness to the OP, this is not easy to search, and is not particularly trivial either. — Bathsheba, Mar 14 '17 at 13:51
Why dont you write your own random depending on previous value + shift? — Malakai, Mar 14 '17 at 13:51
@Bathsheba where is guarantees, that he spent some time on research before posting this question? — Malakai, Mar 14 '17 at 13:52
Hey sorry guys but I've been looking for a solution for this for like 2 hours :( — Wim Schmitz, Mar 14 '17 at 13:55
@WimSchmitz: Methinks you'll need to set aside a good fortnight if your mathematics are rusty. — Bathsheba, Mar 14 '17 at 14:10
@Bathsheba I barely passed statistics last year, mabye that's the problem ;) — Wim Schmitz, Mar 14 '17 at 14:34

score 1 · Answer 1 · answered Mar 14 '17 at 13:49

Sadly statistics doesn't work like that.

You need to define the distribution that you want.
You then get the quantile function for that distribution.
You then draw a uniform number in [0, 1).
You apply the quantile function to (3).

The distribution of (4) will then have the properties that you want.

Random Number generator with skewness

1 Answers1