What is a probability density function?

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NTT
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What is a probability density function?

Post by NTT » Tue Aug 28, 2018 2:53 pm

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?

Post by Intaver Support » Tue Aug 28, 2018 2:55 pm

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.

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