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About POP-III: the Monte Carlo approach

Fossil Creek Software has designed a new companion program to POP-II, called POP-III. It can be used either as a stand-alone modeling program, or as a post-processor to POP-II.

POP-III represents another approach to population modeling based on stochastic (Monte Carlo) sampling. The program offers a choice of uniform, normal, and cumulative distributions for the various survival and fecundity rates, each defined with user­supplied parameters. As with POP-II, the user enters, edits, and reviews the input data and runs simulations to determine the consequences. If used as a post-processor to POP-II, POP-III will analyze the results of the previous simulation and decide on the best probability distribution for the population's variables.

Here are some of the considerations to keep in mind when choosing the best modeling software for your needs:

  1. Whereas POP-II is best suited for animal populations with relatively stable mortality patterns from year to year, POP-III may be used for most any population.
  2. Though both are cast for hunted populations, either may be used on non-hunted populations.
  3. POP-III may also be used for endangered species as it assesses the probability of extinction.
  4. POP-III has somewhat less potential for applied population modeling and much more potential for learning the principles of population dynamics. It implicitly covers the principles of probability distributions, sampling theory, risk analysis, and exceedence values, i.e., the probability that an event of a given magnitude (a bad winter for example) is equaled or exceeded.
  5. POP-II's strength is understanding the past and present population parameters. POP-III's strength is understanding possible futures.
Please refer to the documentation, POP-III_Documentation.PDF(200 KB; requires Adobe Acrobat Reader, available free of charge from Adobe), if you wish more details.