Biology geeks would know that biotic potential is the capacity of a population to increase. It is quantified with the letter r, as in exp(rt), which finance geeks may recognize as the interest rate. r is determined by the balance between birth rate, death rate, emigration and immigration. The physics geeks may set up a nice continuity equation for the population, where migration is expressed as a divergence and birth/death are expressed as reaction sources and sinks.
Now, for the math geeks it may be interesting to note that r has a bounded range for most systems. This means that r>0 inside the range, r=0 at the range (the definition of the range), and r<0 outside the range. In other words, inside the range, you have population growth (or portfolio growth for the investors), outside the range, you have population die-off (or financial destruction. It is not hard to imagine the range changing with areas becoming uninhabitable or investments turning sour in a changing macro-environment. Russia, for instance, has been experiencing a population decline, perhaps as function of both.
The policy geeks (or is that wonks?) will be interested to note that r can be manipulated. What policy geeks often ignore is that this changes the domain; maybe they should consult with the math geeks, or perhaps operational analyst geeks. Population will increase faster/slower if females give birth younger/older. Countries or religions that depend on vertical transmission of affiliation (that is, you are born in to, check with your meme/sociology geek) will often encourage methods that cause earlier child birth and discourage methods that encourage later child birth. Organizations that depend on horizontal transmission (e.g. your peers rather than your parents) will encourage the opposite preferring quality over quantity. What kind of transmission does investing depend on? Your economics geek will probably say vertical for macro and horizontal for micro.
Jacob, Geek of all trades.
Originally posted 2009-04-07 15:09:33.