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Boolean Model


In most modern literature, a Boolean model is a probabilistic model of continuum percolation theory characterized by the existence of a stationary point process X and a random variable rho which independently determine the centers and the random radii of a collection of closed balls in R^d for some d.

In this case, the model is said to be driven by X.

Worth noting is that the most intuitive ideas about constructing a feasible model using X and rho often lead to unexpected and undesirable results (Meester and Roy 1996). For that reason, some more sophisticated machinery and quite a bit of care is needed to translate from the language of X and rho into a reasonable model of continuum percolation. The formal construction is as follows.

Let X be a stationary point process as discussed above and suppose that X is defined on a probability space (Omega_1,F_1,P_1). Next, define the space Omega_2 to be the product space

 Omega_2=product_(n in N)product_(z in Z^d)[0,infty)
(1)

and define associated to Omega_2 the usual product sigma-algebra and product measure P_2 where here, all the marginal probabilities are given by some probability measure mu on [0,infty). Finally, define Omega=Omega_1×Omega_2, equip Omega with the product measure P=P_1 square P_2 and usual product sigma-algebra. Under this construction, a Boolean model is a measurable mapping from Omega into N×Omega_2 defined by

 (omega_1,omega_2)|->(X(omega_1),omega_2)
(2)

where here, N denotes the set of all counting measures on the sigma-algebra B^d of Borel sets in R^d which assign finite measure to all bounded Borel sets and which assign values of at most 1 to points x in X.

One then transitions to percolation by first defining the collection of so-called binary cubes of order n

 K(n,z)=product_(i=1)^d(z_i2^(-n),(z_i+1)2^(-n)]
(3)

for all