<div>I'd written an expression for the expected number of seats for a state whose quotient, resulting from division by the final divisor, is between a and b.</div><div> </div><div>I didn't have an expression for such a state's expected population.</div>
<div> </div><div>I'm going to suggest a way of getting that quantity, though I'm not claiming that it's the most efficient or convenient way.This is just the first way that occurs to me at the moment.</div><div>
</div><div>Find the inverse of S(x), S(x) is the interpolating exponential function that I spoke of in my other post about this, so that inverse will be a logarithmic function.</div><div> </div><div>Population, expressed in the unit that I spoke of, as a function of state number. I'll call that P(s), where s is the state number and P is the population.</div>
<div> </div><div>If S(x) is A*e^(-k*x), where A and k are constants, then x = (-1/k)*ln(s/A). Since I'm calling x "P(s) now, then P(s) = (-1/k)*ln(s/A).</div><div> </div><div>If P(s) is summed between the limits of S(a) and S(b), and the result divided by (S(b)-S(a)), that (at least it seems to me tonight, as my first impression) is the expectation for the populaton of a state whose population is somewhere between x=a and x=b.</div>
<div> </div><div>Then divide the expected number of seats for that state (for which an expression was written in my previous post about this), by that expected population, to get the expected s/p of a state whose population is somewhere between a and b.</div>
<div> </div><div>Set that equal to 1, and solve for R.</div><div> </div><div>That gives the roundoff point for the interval between a and b. That expression, in terms of a and b, when found, is what defines a divisor method, such as this Weighted Webster divisor method.</div>
<div>It differs from Hill, Webster, etc., only in that it takes more work to calculate the roundoff point, R. Hill requires a little more calculation than Webster. Weighted Webster requires more than that--starting with finding the constants, A and k, for the interpolating function, S(x).</div>
<div> </div><div>When Warren and I discussed this subject around the beginning of 2007, on EM, I posted a definition of Weighted Webster then too. I don't know how much it resembles what I've posted here.</div><div>
(I haven't been able to find it yet, in the archives).</div><div> </div><div>I've only just begun to take a look at this problem, just before it was necessary to leave the computer earlier this evening. And now I've posted what has just occurred to me as a possible solution.</div>
<div>Of course this is tentative, because it's only a first look at the problem.</div><div> </div><div>It's late, and I should get off the computer, but I just wanted to post this sketch of Weighted Webster. WW is unbiased, if the interpolatng function S(x) is assumed accurate in the interval from a to b, for which the rounding point R, is being calculated. Of course the whole process, including finding the interpolation function's constants, k and A, would have to be done separately for each interval between two integers, on the population number line.</div>
<div> </div><div>Mike Ossipoff</div><div> </div><div> </div><div> </div><div> </div>