An URN model study of variability within a compartment

Moment solution to an urn model

“…Thus at the i-th cycle, the j-th color 8 (j = 1, 2,..., s) is replenished by rji balls (~,j=l rji = Ri); the cycle is completed by randomly removing Di balls, which may be of different colors; the depletion at any cycle can not in general exceed the urn content at that cycle. This urn model was basically introduced by Bernard (1977). The scheme is displayed in Table 1.…”

“…The basic notion of relating a problem in health physics to classical probability urn models is due to Bernard (1977). Bernard's urn was assumed to contain n red balls (representing dangerous material) of radioactive atoms and b white balls of stable structure.…”