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Comment by cpitman | Hacker News Reader

Any plans to add different probability distributions? I do this kind of analysis by hand for things like project timelines and cost estimates, but I model each variable with a double triangular distribution (http://www.mhnederlof.nl/doubletriangular.html). You provide a best case, worst case, and then the most likely case. The distribution approximates the long tails on many kinds of distributions.

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Definitely. I haven't yet had a request to do a double triangular distribution, that looks really interesting.

It will be a bit of a challenge to make it intuitive, but I'm sure I'll figure out something.

Just so you know, right now there is a second distribution, uniform. You can access it by clicking the 'normal' icon in a normal distribution, where a short list is shown below.

I just made an issue on github, but the uniform distribution looks wonky at the right endpoint.

Much of that is because the react histogram library I used. There are a bunch of issues with it. I definitely intend to replace it with something much better. If any of you recommend tools or libraries for that, I'd be very appreciative.

I do the same thing as cpitman, try to figure project times and costs using the same best, worst, most likely. It would be nice to have it automated so when the PHB looks at the numbers they just don't pick the "best case" because we have the "best team". 50 nodes would be plenty, I can roll up tasks into a bigger task set.

I worked on a while for a product to do this. It foundered on the stony shores of my unfamiliarity with angular, which was the sexy new thing at the time.

+1 for more distribution shapes, specifically power law, combinations of power and normal (Which you might want to consider for your soft-attack-long-tail variables over triangular, if the edge between triangles causes you artifacts), and distributions based on empirical collections.

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