#### Hypergeometric Probability Distribution Calculator (ALPHA)

## About the HPDCalculator

- The "Space" is the sample space, i.e. the number of marbles in bag in the bag of marbles example
- The "Desirables" are the number of desirable objects within the space, so, if you have a bag of marbles, and 30 of them are red and 60 of them are blue, and you want a red one, 30 would be your "desirables" number
- The "Undesirables" are the number of undesirable objects within the space, i.e. the blue marbles
- It is only necessary to specify either the desirables or the undesirables, not both, since they are assumed to be complimentary.
- The "sample" is the number of objects you are extracting from the space without replacement to consider statistically. "Take x marbles from the bag."
- The "Start" and "Stop" values are for specifying which probabilities you want to view. The probability of drawing (start) through (stop) objects. See the "note about precision" to understand why these options are here. If they are not set, they will automatically be considered to be 0 and the sample size.

**A note about precision**
The Hypergeometric Probability Calculator uses the second major revision of Adsci's experimental php math library. It supports additional features such as automatic arbitrary precision, and a more precise calculation engine. Furthermore, it is not limited by parameters any longer (sample size, etc) however, it will "mercy out" after a certain amount of time elapses possibly resulting in… no results. If you run the calculator and end up with either no output (meaning your browser stops, and the page is lacking any results) try adjusting the range of the sample you display (start and stop). Consider breaking it up into pieces. If you end up with a bunch of results which are all zeros, the automatic arbitrary number analysis system has "mercy'd out." Try adjusting the range of your results that you display (start and stop).

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