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Differences between revisions 13 and 14
 ⇤ ← Revision 13 as of 2008-02-13 10:49:16 → Size: 681 Editor: PeterWatson Comment: ← Revision 14 as of 2008-02-13 10:49:57 → ⇥ Size: 689 Editor: PeterWatson Comment: Deletions are marked like this. Additions are marked like this. Line 10: Line 10: 2^text{-0.05}((ln(2)^text{0.05}) = approx. 0.95. 2^text{-0.05}((ln(2)^text{0.05})) = \mbox{approx. 0.95.}

# How do I produce random variables which follow a negatively skewed distribution?

Most distributions such as the exponential and log-Normal distributions are positively skewed with the mode of the distribution occurring for lower values.

The Weibull distribution is negatively skewed and may be generated [http://www.taygeta.com/random/weibull.xml using random variables which are uniform on the interval [0,1]]

The below produces an open ended negatively skewed weibull distribution with parameters, 2 and 20. It has a median of

\$\$ 2text{-0.05}((ln(2)text{0.05})) = \mbox{approx. 0.95.} \$\$

```compute wrv= (-(1/2)*(ln(1-rv.uniform(0,1))))**(0.05).
exe.```

None: FAQ/gamma (last edited 2013-03-08 10:17:36 by localhost)