[R] Latin hypercube sampling from a non-uniform distribution

[Marine Regis]

Thanks for your answer.

I have attached the plot for representing the variable. I think that I need to draw a Hypercube sample for each age class (i.e., for 0, 1, 2, 3, 4, 5, 6, 7) in a given simulation (i.e., N = 1) and the LHS values for all age classes should be like the observed cumulative distribution (see attached figure). Thus, the output of randomLHS should be a matrix with 100 rows (N = 100 simulations) and 7 columns (7 age classes) containing LHS values and each row should exhibit the same pattern as the observed cumulative distribution.
With the command “qpois(X[, "mortality_probability"], 0.9)”, I don’t obtain a LHS value for each age class and the distribution is not a cumulative distribution as in the attached figure. So, I am afraid I don’t know how to do that.
Thanks so much for your time
Marine



________________________________
De : S Ellison <S.Ellison at LGCGroup.com>
Envoyé : mardi 8 août 2017 14:48
À : Marine Regis; r-help at r-project.org
Objet : RE: Latin hypercube sampling from a non-uniform distribution

> However, my variable is simulated from the cumulative distribution function
> of the Poisson distribution.
Then I am afraid I don't know what you're trying to achieve.
Or why.

However, the principle holds; write a function that maps [0,1] to the 'pattern' you want, do that and apply it to the result from randomLHS.
It happens that for generating data that follow a given probability distribution F, that function is the quantile function for F so you often do not need to write it.






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