I suppose Dennett is implying that the linear congruential generator below
would take at least the number of bits in variables a, b, m, and x[0]. If
those are 1-byte integers, then the bit count is at least 32 bits. There’s
overhead for the actual code too. How do you measure that? Suppose the
answer is 100 bits for the code including state. Then if you use it to
generate a sequence of one gazillion values, that sequence would only
contain the equivalent of 100 bits of information because it can be
generated by a 100 bit algorithm.

 

I still suspect there might be circular logic here. Do we place no value on
the energy needed to generate it? 

 

What if our entire universe can be described in a very simple equation that
is just generated recursively or fractally by many iterations? If that
equation was less than a megabyte, then would we argue that the entire works
of Shakespeare must have less information?

 

  _____  

From: friam-boun...@redfish.com [mailto:friam-boun...@redfish.com] On Behalf
Of Roger Critchlow
Sent: Thursday, April 23, 2009 12:37 AM
To: nickthomp...@earthlink.net; The Friday Morning Applied Complexity Coffee
Group
Subject: Re: [FRIAM] random vs pseudo-random

 

 

On Thu, Apr 23, 2009 at 1:05 AM, Nicholas Thompson
<nickthomp...@earthlink.net> wrote:

 

Can anybody help me understand this.  (Please try to say something more
helpful than the well-deserved, "Well, why do you THINK they call it
pseudo-random, you dummy?")What DOES a pseudo randomizing program look like?


 


This one is called a linear congruential generator:

x[i+1] = (a * x[i] + b) modulo m


x[i] is the current random number, x[i+1] is the next random number, for
appropriate choice of a, b and m the sequence of numbers produced will go
through all the numbers from 0 to m-1 in some order over and over again.

The choice of a = 1, b = 1 enumerates in increasing order, and the choice of
a = 1, b = -1 enumerates in decreasing order.  Neither is a very good
choice, but they aren't the only bad choices.  For instance, a = 0 is
probably the worst choice of linear congruential multiplier.

You might try out different values for a and b in a spreadsheet with m = 17.
Or just do it on paper.

-- rec --

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