Joint distribution is regulated by 7 joint characteristic elements ; 1) orientation, 2) persistence, 3) density, 4) aperture, 5) filling, 6) roughness and 7) conductivity. For the purpose of making a stochastic space model of each joint characteristic element is defined as the results of the field investigations, Each joint set has its own distributional character. Therefore, each probabilistic space model must be probability density function conditional upon joint set.
