Re: Information: Brad's reply (was Information: a very

Glenn R. Morton (grmorton@waymark.net)
Mon, 29 Jun 1998 20:30:19 -0500

At 02:02 PM 6/29/98 -0700, Greg Billock wrote:
>> >Nobody knows what that fraction is, or even where exactly the most
>> >crucial parts are. So similar to the "0" message, it is a hard
>> >problem to try to figure out what information theory might do for us
>> >in biology.=20
>>
>> The only way I see that the '0' message applies to DNA is if you are =
>> suggesting that there are other nucleotides of which we are unaware. As =
>> you suggested with the '0' message, "Since there is basically no way to =
>> detect what a one-shot information source could have done, there is
>> no way to model the distribution of its possible messages, and
consequentl=
>> y no way to figure out how much information was gotten. Was I restricting =
>> myself to {0, 1}? to numerals? to one-digit
>> keyboard taps? with some weird probability distribution on them?
unrestrict=
>> ed length?"
>>
>> But with DNA, we have only 4 nucleotides and thus KNOW what we are =
>> restricted to. This should make the information content calculable. What =
>> am I missing here?
>
>The other 2,999,999,999 nucleotides in the sequence. :-)

I think I must have miscommunicated here. The information content of a
sequence is related to the ENTIRE sequence, all 2,999,999 of them. There
are only 4 letters in the DNA alphabet. That was what I was meaning with
the 4 nucleotides. I was NOT referring to a 4 nucleotide long DNA
molecule. Go back and re read what I said in that light.

I still don't think we need to know how many of the possible 3 billion long
DNA chains yield life to calculate information.
glenn

Adam, Apes and Anthropology
Foundation, Fall and Flood
& lots of creation/evolution information
http://www.isource.net/~grmorton/dmd.htm