## What is a probability density function?

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### What is a probability density function?

In some documentation about Monte Carlo estimates, it seems that they are been referred to as statistical distributions and probability density functions. Is the probability density function the same thing?
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### Re: What is a probability density function?

In statistics, statistical distribution and probability density (PDF) functions describe the same thing and can be considered interchangeable. PDFs mathematically describe the probability that an outcome will occur over a range of possible outcomes. In the example below, we have a triangular distribution that ranges from 40 to 60 days with a most likely at 46 days (x axis). On the y-axis, we can see the probability that any value will occur. For example if we draw a straight line across from the highest probability, which is the most likely estimate of 46 days, we can see that this value has .1 or 10% chance of occurring. Intaver Support Team
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