Difference between revisions of "Three parameter beta distribution estimation procedure"

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[[File:BetaDistributionFourParameters.png|300 px|thumb|right|Form. 1.]]
 
[[File:BetaDistributionFourParameters.png|300 px|thumb|right|Form. 1.]]
 
This formula has two extra parameters ''a'' and ''c'', which can be used to normalise the distribution to [0,1] with ''y = (c-a)x + a''. As nutritional values always start at 0, we assume that ''a = 0''. With this we can rewrite formula 1:
 
This formula has two extra parameters ''a'' and ''c'', which can be used to normalise the distribution to [0,1] with ''y = (c-a)x + a''. As nutritional values always start at 0, we assume that ''a = 0''. With this we can rewrite formula 1:
<iframe frameBorder="0" width="100%" height="100%" style="min-width: 400px; min-height:400px" src="https://www.mathcha.io/editor/pPzgOF6yI3nHLmp8K9COol96JcN2Ypnos2Ln7e?embedded=true" ></iframe>
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As MediaWiki does not supports maths (yet), have a look at [https://www.mathcha.io/editor/pPzgOF6yI3nHLmp8K9COol96JcN2Ypnos2Ln7e this]

Latest revision as of 14:22, 9 October 2024

No procedure for a three parameter estimation can be found on Internet, so we have to come up with something.

The starting point is the four parameter Beta distribution found on wikipedia:

Form. 1.

This formula has two extra parameters a and c, which can be used to normalise the distribution to [0,1] with y = (c-a)x + a. As nutritional values always start at 0, we assume that a = 0. With this we can rewrite formula 1:

As MediaWiki does not supports maths (yet), have a look at this