

The Alias Method is an O(1) algorithm to select elements from a distribution - tectonic
https://github.com/cantino/walker_method

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filpen
While looking up Walker's Alias Method I ended up here
[http://forums.udacity.com/questions/1012915/resampling-
walke...](http://forums.udacity.com/questions/1012915/resampling-walker-alias-
method) , where people say it is not Walker's method, but Vode's. I can't
verify it right now but I thought it might be of interest anyway.

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pgsandstrom
"You could also use ranges, picking a random number between 0.0 and 1.0 and
returning :win when the number is below 0.8, :lose otherwise. But, these
algorithms are still O(n)"

Maybe my math is a bit rusty, but is this really O(n)? Why is that?

~~~
andreer
n here is the number of different elements you can choose from. If there was a
third alternative, you'd have to add another if statement.

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andreer
An excellent writeup on different techniques to do this:
<http://www.keithschwarz.com/darts-dice-coins/>

