Feature Request: Add Beta 4 parameters distribution

[guilhermebodin]

Is it possible to include the Beta four parameters parametrization in the package?
The 4 parameter distribution is described in the section "Four parameters" https://en.wikipedia.org/wiki/Beta_distribution

[johnczito]

This is secretly already implemented. In the wiki it says that the 4-parameter beta Y over an interval (a, c) is given by a transformation of an ordinary beta X:

Y = (c - a)X + a. 

This means that a 4-parameter beta is a Location-Scale transformation of a regular Beta, which is implemented via

a = -1
c = 1
beta = Beta(1, 1)
beta4par = LocationScale(a, c - a, beta)

[johnczito]

#971 is related to this.

[guilhermebodin]

hmm, I knew it was easy to reformulate it thanks a lot!

[johnczito]

Any time. Is it okay to close this?