user3624322 user3624322 - 1 year ago 107
R Question

Sampling from a pareto distribution in R - getting values below scale parameter

I am sampling from a Pareto distribution using rpareto from package actuar.

What I find strange is that I keep getting values below the defined scale parameter. I was under the impression they should all be above it.

tail <- rpareto(2,scale=y_0,shape=a_hat)

and I get in my vector values below y_0. Does anyone have an explanation?


Answer Source

Check the formulation used by the function in the ?rpareto help page. Perhaps they parameterized the distribution differently than you do. From the help page:

enter image description here

So they say that the returned values with be >0. The support does not depend on the parameters.

If you are comparing this to the version on wikipedia they are basically doing a translation of

y = x - scale
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