Many methods are used to measure the spatial distribution. They are all different version of what some call beta-diversity or auto-correlation function. The most robust method is to divide the space into quadrants (square ) of size "L", and count the number of individual in each square. The mean (mu) and Variance (V) of these number are the firs level of quantification. Specifically, the ratio of V/mu and its comparison to unity is important.

After the first level of analysis, one can look into correlation between quadrants, or (V,mu) as a function of quadrant size. If L was small at the beginning, we can bin them. The functions V(L) and mu(L) have much information.

Basically, you can test any mathematical model against this set of measurements for validation/rejection.

Dear Oulaid, the attached paper offers some mathematical (statistical) models and methods to describe some physical characteristics of dinosaurs; perhaps it could be useful for your model.

Gianluca

Species distributions can be modelled using presence-abscence data. You can also determine whether the species are randomly, uniformly, or clumped in their spatial distribution. And there are also niche modeling algorithms :)

Thank you dear colleagues for your successful answers