Date: Tue, 17 Aug 1999 09:33:31 +0200
From: "Gatherer, D. (Derek)" <D.Gatherer@organon.nhe.akzonobel.nl>
Subject: RE: Defection Rates and Classes (was Parody of Science)
To: "'memetics@mmu.ac.uk'" <memetics@mmu.ac.uk>
Here's Tim's revised model:
# Perl 5.005
# establishing input/output stream
open(OUTFILE, '>outfile.xls') or die "can't find the outfile $!\n";
print "\nPlease enter the following variables.";
print "\nnumber of people in the professional class: ";
chomp ($P = <STDIN>);
print "\nnumber of people in the working class: ";
chomp ($W = <STDIN>);
print "\nthe reproductive rate of the professional class: ";
chomp ($Rp = <STDIN>);
print "\nthe reproductive rate of the working class: ";
chomp ($Rw = <STDIN>);
print "\nthe inter-class defection rate downwards: ";
chomp ($D_down = <STDIN>);
print "\nthe inter-class defection rate upwards: ";
chomp ($D_up = <STDIN>);
print "\nthe number of cycles to simulate over: ";
chomp ($cycle = <STDIN>);
print OUTFILE "cycle\tprofessionals\tworkers\t%prof.\ttotal pop.";
print OUTFILE "\n0\t$P\t$W";
for ($round = 1; $round <= $cycle; $round++)
{
$P = ($P * (1-$D_down) * $Rp) + ($W * $D_up * $Rw);
$W = ($W * (1-$D_up) * $Rw) + ($P * $D_down * $Rp);
$percent_prof = (100*$P)/($P+$W);
$total_pop = $P + $W;
print OUTFILE "\n$round\t$P\t$W\t$percent_prof\t$total_pop";
}
and here's some sample output.
starting pop was 100 prof. to 900 worker, and I chose reproductive rate for
prof. class at 0.4 (ie. 0.8 children per couple) and for workers at 1.5 (ie
3 children per couple) Defection downwards was chosen to be 10% and upwards
to be 5%. Under these circumstances, the population increases at some 40%
per generation, and the percentage of professional classes declines to an
equilibrium level of about 6.6% effectively stable from generation 7
onwards.
Okay, any bids for realistic values? Shall we start with a pre-dem.trans.
society?
Output: (may not format......????)
cycle profession workers %prof. total pop.
0 100 900 10 1000
1 103.5 1286.64 7.44529328 1390.14
2 133.758 1838.81232 6.780898944 1972.57032
3 186.063804 2627.750108 6.612512761 2813.813912
4 264.0642276 3755.106473 6.570117251 4019.170701
5 376.6961074 5366.094569 6.559460873 5742.790676
6 538.0676913 7668.207468 6.556783448 8206.275159
7 768.819929 10957.94844 6.556110813 11726.76837
8 1098.621307 15659.02138 6.555941835 16757.64269
9 1569.930274 22376.90267 6.555899385 23946.83295
10 2243.442599 31976.82402 6.555888721 34220.26661
11 3205.901137 45695.21027 6.555886042 48901.1114
12 4581.265179 65298.92524 6.555885369 69880.19042
13 6546.674857 93312.83546 6.5558852 99859.51032
14 9355.265608 133345.0012 6.555885157 142700.2668
15 13368.77071 190551.3775 6.555885147 203920.1482
16 19104.11076 272299.8773 6.555885144 291403.9881
17 27299.97067 389119.324 6.555885143 416419.2947
18 39011.93874 556055.5143 6.555885143 595067.453
19 55748.46152 794609.0463 6.555885143 850357.5078
20 79665.12462 1135504.496 6.555885143 1215169.621
21 113842.2821 1622647.598 6.555885143 1736489.88
22 162681.7914 2318780.099 6.555885143 2481461.89
23 232473.9523 3313560.599 6.555885143 3546034.551
24 332207.6678 4735112.16 6.555885143 5067319.828
25 474728.1724 6766523.955 6.555885143 7241252.128
26 678391.4387 9669432.294 6.555885143 10347823.73
27 969428.34 13817718.15 6.555885143 14787146.49
28 1385323.064 19745661.29 6.555885143 21130984.35
29 1979640.9 28216752.97 6.555885143 30196393.87
30 2828927.197 40322030.07 6.555885143 43150957.27
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