Dawkins’ WEASEL: Proximity Search With or Without Locking?

_{William Dembski
March 16, 2009

Darwinism, Evolution, Informatics

3}_{Categories
Darwinism
Evolution
Informatics}

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On pp. 47-48 of THE BLIND WATCHMAKER, Richard Dawkins gives two runs of his WEASEL program (note that there were typos in both initial seeds — one had 27 characters, the other 29 whereas they should have 28; I’ve corrected that). Here are the two runs using the Courier typeface, which assigns equal width to each character (spaces are represented by asterisks):

WDL*MNLT*DTJBKWIRZREZLMQCO*P
WDLTMNLT*DTJBSWIRZREZLMQCO*P
MDLDMNLS*ITJISWHRZREZ*MECS*P
MELDINLS*IT*ISWPRKE*Z*WECSEL
METHINGS*IT*ISWLIKE*B*WECSEL
METHINKS*IT*IS*LIKE*I*WEASEL
METHINKS*IT*IS*LIKE*A*WEASEL

Y*YVMQKZPFJXWVHGLAWFVCHQXYPY
Y*YVMQKSPFTXWSHLIKEFV*HQYSPY
YETHINKSPITXISHLIKEFA*WQYSEY
METHINKS*IT*ISSLIKE*A*WEFSEY
METHINKS*IT*ISBLIKE*A*WEASES
METHINKS*IT*ISJLIKE*A*WEASEO
METHINKS*IT*IS*LIKE*A*WEASEP
METHINKS*IT*IS*LIKE*A*WEASEL

These runs are incomplete. The first, according to Dawkins, required 43 iterations to converge, the second 64 (Dawkins omitted the other iterates to save space).

As you can see, by using the Courier font, one can read up from the target sequence METHINKS*IT*IS*LIKE*A*WEASEL, as it were column by column, over each letter of the target sequence. From this it’s clear that once the right letter in the target sequence is latched on to, it locks on and never changes. In other words, in these examples of Dawkins’ WEASEL program as given in his book THE BLIND WATCHMAKER, it never happens (as far as we can tell) that some intermediate sequences achieves the corresponding letter in the target sequence, then loses it, and in the end regains it.

Thus, since Dawkins does not make explicit in THE BLIND WATCHMAKER just how his algorithm works, it is natural to conclude that it is a proximity search with locking (i.e., it locks on characters in the target sequence and never lets go).

Interestingly, when Dawkins did his 1987 BBC Horizons takeoff on his book, he ran the program in front of the film camera:

www.youtube.com/watch?v=5sUQIpFajsg (go to 6:15)

There you see that his WEASEL program does a proximity search without locking (letters in the target sequence appear, disappear, and then reappear).

That leads one to wonder whether the WEASEL program, as Dawkins had programmed and described it in his book, is the same as in the BBC Horizons documentary.

In any case, our chief programmer at the Evolutionary Informatics Lab (www.evoinfo.org) is expanding our WEASEL WARE software to model both these possibilities. Stay tuned.

Comments

David Kellogg, So what I said was not only correct about what was on the Monash website but what I pointed to was essentially the same thing as the Dawkins weasel program. The two programs are very different and one only has to run them to know that they take a different amount of time and iterations and proceed much differently. I suggest that everyone here who has followed this discussion go to the Monash website and try out the two different versions. The Dawkins version has all sorts of variations and you can put in any word string you want.jerry_{March 26, 2009
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PS: Illustrate, Am HD: il·lus·trate (l-strt, -lstrt) v. il·lus·trat·ed, il·lus·trat·ing, il·lus·trates v.tr. 1. a. To clarify, as by use of examples or comparisons: The editor illustrated the definition with an example sentence. b. To clarify by serving as an example or comparison: The example sentence illustrated the meaning of the word. 2. To provide (a publication) with explanatory or decorative features: illustrated the book with colorful drawings. 3. Obsolete To illuminate. v.intr. To present a clarification, example, or explanation. --> that which is materially diverse to the point of being misleading, CANNOT properly illustrate.kairosfocus_{March 26, 2009
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Hazel: 1 --> FAIR COMMENT: Weasel is highly misleading if intended to be pedagogical. (So, it only serves a rhetorical purpose, not a properly educational one.) 2 --> JUSTIFICATION, STEP 1: DUTY NO 1 of the educator is not to mislead or manipulate; for by definition he deals with the ones who are least likely to be able to spot and correct error. 3 --> That holds for the public -- pop sci -- educator as well. 4 --> BASIC EVIDENCE: Holistic selection or letter by letter selection [implicit or explicit] makes little or no difference. By Mr Dawkins' direct statement in BW ch 3, courtesy Wiki, Weasel rewards mere proximity not differential function:
We again use our computer monkey, but with a crucial difference in its program. It again begins by choosing a random sequence of 28 letters, just as before ... it duplicates it repeatedly, but with a certain chance of random error – 'mutation' – in the copying. The computer examines the mutant nonsense phrases, the 'progeny' of the original phrase, and chooses the one which, however slightly, most resembles the target phrase, METHINKS IT IS LIKE A WEASEL.
5 --> IMPLICAION: This is plainly foresighted choice based on mere proximity increment, not differential functionality, by programmed -- intelligently preset -- choice. 6 --> WARRANTED CONCLUSION: So Weasel cannot properly model the claimed blind watchmaker, natural selection. And, that is long before implicit or explicit latching or quasi-latching become an issue. ______________ RECOMMENDATION: WEASEL SHOULD BE WITHDRAWN AND CORRECTED, if it is intended to serve a legitimate didactic purpose. GEM of TKIkairosfocus_{March 26, 2009
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hazel:
But this non-latching/latching issue is a critical aspect of reality that Weasel does capture: in Dawkins non-latching model, mutation is random in respect to fitness, and in Dembski’s latching model it is not.
Prove it. IOW prove that Dembski's random muation is any different than Dawkins. Ya see in the "weasel" program there is a target- and that means FOREKNOWLEDGE. All offspriing are compared to the target. And a target equals teleology. As for modeling something- Dawkins was NOT modeling evolution with the weasel program. He was ILLUSTRATING cumulative selection. And the way he illustrated AND described cumulative selection it is a ratcheting process that locks the matching letters into place. Deal with it.Joseph_{March 26, 2009
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kairosfocus [318], for this entire thread it has been clear that you are wrong. Your statistics have been wrongly applies (as Wesley Elsberry showed repeatedly), your assumptions have been taken out of thin air, and your evidence has been fantasy (elevating a pedagogical example to a random sample). Why you continue to write as though you were correct all along? The first point in your latest list would seem to make your labors on latching irrelevant rather than wrong. Which is it? Joseph [319], is 5% an unreasonably high mutation rate? Dawkins assumes that readers are able to follow him. He never sets limits on what can mutate, and he mentions that the chosen string is closest to the target -- meaning closest as a whole. Letters can, therefore, revert, even though the whole will continue to move closer to the target. Cumulative can include losses. Zachriel text provides (with citations) the following examples from mountain climbing, which you claimed [299] above would never be used that way:
Walkers: ‘Easy' means that the cumulative height climbed during the walk is less than 300ft ‘Moderate' means that the cumulative climb is between 300ft and 1000ft and ‘hilly' means the cumulative climb is over 1000ft. Runners: The cumulative climb for this run is 16,000 feet and only two people have completed this challenging run! Bikers: From the trail head, it's about 1.5 miles to the new bridge. There are some technical switchbacks on the 5 climbs of this section (cumulative climb 800 feet). Climbers: My avocet watch indicated a cumulative climb of 28,650ft. We read the words on the summit memorial to the 2 skiers killed by avalanche in 1988.
David Kellogg_{March 26, 2009
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David, at what is currently 317, makes a critical point about this latching/non-latching issue. He writes,
Here’s how Weasel works: Changes take place randomly, at the level of the letter (analogous to the gene); selection takes place holistically, at the level of the whole phrase (analogous to the organism). The problem with the “latching” version is that selection takes place at the level of the letter, and so the model completely misrepresents what Dawkins originally described. If you write a program that chooses what letters survive, you haven’t modeled anything; if you write a program that chooses what phrase survives, you’ve created a model — maybe a crude one, but a model nonetheless — of what happens in nature.
This point has also been made by several others upstream in the thread. I’d like to add my 2 cents. In the unlatched, proximity case the mutation routine knows nothing about the fitness routine: it is truly random in respect to fitness because nothing about the fitness routine influences how the phrase mutates. The mutation function operates letter by letter without any knowledge of the fitness function, and then later the fitness function acts holistically on the phrase as a whole without regard to what just did or did not mutate. The functions act independently of each other. This accurately models an important principle about how evolution works. On the other hand, in the Dembski latching partitioned search, the mutation routine has to constantly know about, or have received information from, the fitness routine in order to function because it has to ask “is this letter correct” before it decides whether to even consider whether to apply the possibility of mutation to the letter. This is teleological - the mutation function has foreknowledge about what will make the phrase more fit (in the form of knowing which letters are already correct), rather than just doing it's thing and letting fitness sort itself out later. This is not how evolution works. ============ Now before kairosfocus fires off another couple thousand words repeating himself again, let me say that I and everyone else involved here knows that there are some very important ways in which Weasel does not - I repeat, not, model evolution. Weasel is a simple pedagogical model (remember it was written over 20 years ago on a Apple in BASIC), and like all models it only can capture a part of reality. But this non-latching/latching issue is a critical aspect of reality that Weasel does capture: in Dawkins non-latching model, mutation is random in respect to fitness, and in Dembski’s latching model it is not. The former is truly evolutionary, and the latter is not.hazel_{March 26, 2009
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David Kellogg, The issue is NOT whether or not one can make the program "revert". Obviously if you program unreasonably high mutation rates it could do so. That misses the point: Part of the Marks/ Dembski paper discusses a “partitioned search”. To illustrate a partitioned search they refer to the book “The Blind Watchmaker” and the use of the “weasel” program. In TBW Dawkins uses “weasel” to illustrate cumulative selection. “Cumulative” means “increasing by successive additions”. INCREASING BY SUCCESIVE ADDITIONS. “Ratchet” means to “move by degrees in one direction only”. Increasing by additions means to move by degrees in one direction only. Dawkins NEVER mentions that one or more steps can be taken backward. He never says anything about regression. Therefor cumulative selection is a ratcheting process as described and illustrated by the “weasel” program in TBW. That is once a matching letter is found the process keeps it there. No need to search for what is already present. Translating over to nature this would be taken to mean once something useful is found it is kept and improved on. IOW it is not found, lost, and found again this time with improvements. By reading TBW that doesn’t fit what Richard is saying at all. And he never states that he uses the word “cumulative” in any other way but “increasing by successive additions”. How can a process be “cumulative” and at the same time allow you to keep losing what you have? We would call that the “yo-yo” selection process. And then no one would infer it is a partitioned search.Joseph_{March 26, 2009
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Okay: Initial note: I observe there has been a bug in Apollos' pgm, for which he has apologised and put up a correction. Appreciated. The corrected pgm implicitly quasi-locks, it seems at 5%, 500. [And, with such a large population, it may well have multiple- newly- correct- letter, far- skirt members of the binomially distributed population speeding up the approach to the target. That is, this one is tuned for speed, as pointed out above. (I seems clear as well -- even from the buggy example -- that a sufficiently detuned Weasel will show a very slow approach and multiple letter flickbacks. Thus, the point on the material difference between W 1986 and W 1987, per highly contrasting o/p patterns, still stands.)] On the underlying issues: 1--> Weasel, circa 1986, explicitly has rewarded mere proximity to target, without reference to functionality; as the reference in BW at that time to "nonsense" phrases makes clear. 2 --> As such, Weasel cannot be a reasonable analogue to natural selection [i.e. Mr Dawkins' 'BLIND watchmaker'], as NS must cull based on differential reproductive success, i.e. differential functionality in the environment. 3 --> In that context, Weasel cannot reasonably be claimed that it is illustrating anything that is properly didactic, as to present this as a premier example of the blind watchmaker at work when it is in fact a foresighted watchmaker at work, is plainly highly misleading. (We can presume on charity that the fallacy involved was unintentional. Apparent confirmations of our expectations, after all, can be quite misleading. Indeed, that issue is a major part of the context of Popper's work on falsification, and more broadly of the value of testability.) 4 --> Now, of course Weasel circa 1986 is intended to illustrate the power of cumulative selection to find an otherwise hard to reach target. What it succeeds in showing is the power of foresighted cumulative selection to do that, i.e, it exemplified the power of intelligent -- though sub-optimal [there are better search strategies out there] -- design. (And yes, that shows the basic problem of the panda's thumb as an anti-design argument.) Weasel knocks over a question- begging strawman and so fails to address the Hoylean challenge of the threshold of complexity for first life, and onward for body plan level biodiversity. The issue of the origins of functionally specific complex information and evidently irreducibly complex structures in life forms -- e.g. the algorithmic information storing and processing system in the heart of the cell -- stands unanswered by Weasel . . . and, for that matter, its more sophisticated kin of today. (These are of course the key challenges raised by the rising challenger to neo-Darwinian school, Intelligent Design. Weasel and kin, properly understood, illustrate intelligent design in action, not chance variation + natural selection.) 5 --> Unfortunately, ever since 1986, Weasel and kin have persuaded a great many onlookers that Weasel as the iconic example, illustrates BLIND cumulative selection. Thus, it has had far more of a rhetorical rather than a properly didactic impact. 6 --> This should be acknowledged by those who have championed Weasel, and corrected; not excused by remarks on how teachers cannot tell their students "everything" or the like. Sorry, that is simply not good enough. Period. 7 --> Going beyond that, as Joseph has documented [and as is evident from event the Wiki extracts that were used to try to justify Weasel], given the published o/p of Weasel circa 1986, and the explicit statements in BW, it is objectively a legitimate interpretation that Weasel in the original form implemented partitioned, explicitly latched search. So, the attempts to bash and dismiss those who have taken Mr Dawkins at his word circa 1986 should now cease. 8 --> On the context of possibilities for implicit latcfhing, and in light of strength of Mr Dawkins' reported statement that in fact he did not explicitly latch correct letters circa 1986, we have discussed the issue of implicit latching and/or quasi- latching as the most likely explanation of the published 1986 o/p; and I have accepted that this is -- on preponderance of evidence -- the best current explanation. This too, especially given the law of large numbers [onlookers observe the evidently studied silence on that in the past few days, after many attempted dismissals] is a legitimate understanding of the 1986 o/p. 9 --> There have also been attempts to state or imply that the 1987 o/p's were essentially the same as those of 1986. But, since an implicitly latched program with de-tuned parameters will plainly show the multiple flick-back patterns circa 1987 AND a sample of 300 changeable letters with 200 showing "go-correct and hold" is also on the table, such a claim clearly lacks warrant. 10 --> Finally, let us note that "latching" is a secondary issue; one that came up because in a previous thread GLF tried a threadjack based on trying to argue that pointing to this as an aspect of Weasel circa 1986 was a fundamental and discrediting error on my part. Plainly, I made no error on the evidence in hand and reasonable interpretations of Mr Dawkins' words in BW. The primary issue is that Weasel is not at all illustrative of a BLIND watchmaker, but instead of a ~~BLIND~~ FORESIGHTED watchmaker. _____________ Thanks are due to the poster of this continuation on a second thread, once the previous one ran over 600 posts. (And, SG, the issue is not at all that of a fixed notion on WmAD's part, but clarifying and correcting an issue that had become contentious and sidetracked another thread of high significance in its own right; never mind that it illustrated aptly the pattern of selective hyperskepticism in action.) GEM of TKIkairosfocus_{March 26, 2009
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hi jerry, Thanks for the response. If you read the description at Monash, you'll see what Zachriel means.
Note that this demo works slightly different than the model described by Dawkins in his book. We are grateful to Dr. W. R. Elsberry for pointing this out and for highlighting the differences. In the original model the letters do not become fixed. Instead, at each generation (i.e. step) a number of mutant strings are produced from the current copy by randomly changing some letters. The mutants are considered to be chosen for the next generation. The chosen string is the one that most resembles the target string. The results of the model presented here and of the original Dawkins model are essentially the same: at each step either a “better” string is produced or something quite similar to the current version is retained. As a usual consequence, current strings are replaced with new strings that have at least as many matches as the previous one. We have created a more elaborated version of the weasel -- the genetic algorithm weasel. That version incorporates the selection process as it is described by Dawkins and extends his model with some features commonly found in genetic algorithms.
In other words, their two demos get to the target around the same time, but by different methods. But it's the method that models evolution, even slightly, or not. If the criticus don't understand how it works, their critiques are going to be not so much wrong (though they may be that) as beside the point. This is why the Monash programmers admit that the non-latching one -- and that one only -- is the one that "incorporates the selection process as it is described by Dawkins." Here's how Weasel works: Changes take place randomly, at the level of the letter (analogous to the gene); selection takes place holistically, at the level of the whole phrase (analogous to the organism). The problem with the "latching" version is that selection takes place at the level of the letter, and so the model completely misrepresents what Dawkins originally described. If you write a program that chooses what letters survive, you haven't modeled anything; if you write a program that chooses what phrase survives, you've created a model -- maybe a crude one, but a model nonetheless -- of what happens in nature. I'm certainly no expert in this area, and I was relaying Zachriel, but I believe that the debate speaks to a longstanding misunderstanding by the ID critics of what Weasel specifically (and an evolutionary algorithm generally) does, and how such an evolutionary algorithm models evolution even to a limited extent. I believe that this has been pointed out to Dr. Dembski for years, and yet he has persisted in treating Weasel, in his writing and in the EIL program, as though it latched letters. DavidDavid Kellogg_{March 25, 2009
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P.S. OK, I'll quit complaining now. :-)hazel_{March 25, 2009
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I have found all this not only fun, but meaningful. I understand, of course, that such little programs as Weasel are not models of evolution per se, but they have evolved [intended] into very powerful problem-solving techniques and they have taught us a great deal about the power of iterative systems. As I and other have repeatedly said, models of reality have to be tested against reality, and no model can encompass all of the reality that it is trying to represent, but techniques such as evolutionary algorithms, fractal generators, and other mathematical tools that have become feasible with the advent of computers have given us many powerful new tools for understanding the world. So, yes, I think this all means something. I’d also like to point out the value of the kind of discussion some of us have been having - one where questioning and answering about specifics, rather than engaging in rhetoric, has led to greater understanding, even if we continue to disagree about things such as the larger implications of the topic. And I’d really like to see someone take charge and un-moderate people so we can live up to the new moderation policy offered by BarryA on another thread. Barry wrote,
We have no interest in censoring viewpoints, because we believe ID is true and consequently in any full and fair debate we will win — and if we don’t win we either need to learn to debate better or change our position.
I don’t think moderating posts so they don’t show up for hours is in keeping with the spirit of this quote.hazel_{March 25, 2009
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David Kellogg, "Jerry, you write: If anyone want to see the Weasel generator that was created a couple years at Monash University in Australia follow the link I put up above and press demo at the bottom. It uses a latching function. Zachriel responds: Then it isn’t an evolutionary algorithm, and it isn’t Weasel." The comment seems to imply that I was wrong about something. What did I say that was untrue or misleading. The site said that their generator was like Dawkins program and that Elsberry had consulted with them. I passed this information on. They had two generators, one fairly simple looking and one more complicated which they said was similar to Dawkin's model. I am sorry but all I was trying to do was shed some light on the nature of the program by people who had input from Elsberry. There seemed to be a lot of effort to prove some minutiae about this program and I thought this might help clear it up. These programs may be fun but has anyone shown that they mean anything?jerry_{March 25, 2009
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It was requested that I post output from the corrected program. This is the proximity reward search with population 500 and mutation rate 0.05:
Gen 1: mezqjbfsarrvcq vxzxjj kewhrr fit: 21% Gen 27: methinks it is like a weasel fit: 100% -------------- Target reached -------------- Generations: 27 Total population: 13500 Iterations: 742000 Run time: 33ms --------------
This is consistent with the expected results, including hazel's comments above.Apollos_{March 25, 2009
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With reference to the code "pop[i] = pop[winner]" there is definitely a logic error here. Wesley R. Elsberry writes:

for( int i = 0; i < popSize; i++ ) { pop[i] = pop[winner];
Once i > winner, what is used as a template for additional candidates in the new population is the just-mutated new candidate at the winner index. This means that every time that the first candidate in a population wins, whatever mutation that happens to it will be the basis for the whole new population.
The problem in my own words is that once "winner = i" if pop[i] mutates then winner[i] is also mutated, and will then propagate onward. This still leaves a reasonable chance that at least one offspring will be a duplicate of the winner from the previous generation. Here's some output:
Begin Gen -------- Prior winner: mbehrozskiyddrktyf rqwwikfho -------- After mutate: mbehrozskiyddrktyf rqwwikfho After mutate: ykqhrozskiyddrktyf rqwkikfho * After mutate: mbehrozskiyddrktyf rqwwikbho * After mutate: mbehrozskiyddrktyf rhwwikfho * After mutate: mbehrozskiyddrktyf rqwwikfho After mutate: mbehrozskiyddrktyf rqwwikfhy * After mutate: mbesrozskiyddrktyk rqwwikfho * After mutate: mbehrozskiyddrktyf rqwwikfqo * After mutate: mbghrozskiyddlmtyf rqwwikfvo * After mutate: mbehrooskiyddrktyf rqwwijfho *
Asterisks indicate strings which differ from the winner. This doesn't turn out to be frequent enough to overcome the problem. This is because the evaluation loop always keeps the lowest winner, instead of the highest, so the winner is copied and mutated sooner rather than later in the propagation loop. Making this change:
from if( score > highScore ) to if( score >= highScore )
causes the problem to almost vanish, even with the bug still present. The real fix is simple:
string strWinner = pop[winner]; for( int i = 0; i < popSize; i++ ) { pop[i] = strWinner; ...
Thanks to Mr. Elsberry for spending time with the code. It's good to know that someone actually went through it, even if the intention wasn't constructive criticism. Thanks to hazel for bringing it to my attention, no offense was taken. My apologies for the error, without excuse. ;-)Apollos_{March 25, 2009
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This is confusing - it seems like there are now posts upstream that weren't there before. When someone has posts being moderated, when they finally go through they appear back at the time they were posted, so unless one keeps looking back one doesn't know they happened. This is really unsatisfactory. Not only that, post numbers change, so if one has referred to post 285, for instance, the reference is now wrong because a moderated post has been added. Why are posts being held up in moderation at all???!!! This is really weird.hazel_{March 25, 2009
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Atom and others (Joseph, jerry, kairosfocus): I posted a run of Weasel that reverts above [283] and relayed some responses from Zachriel in [285]. I mention it now because both posts were caught in moderation for awhile and might otherwise be lost. Thanks.David Kellogg_{March 25, 2009
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Oops, I meant thanks Apollos.hazel_{March 25, 2009
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Thanks, Atom. Bugs are inevitable - I know that, and I didn't mean to offend you. I really appreciate that your willing to be part of this conversation. Getting a program that works so we can test some of the ideas being discussed would be useful. Now, a question: Do you agree with my analysis that under a partitioned search reversals in fitness, especially towards the end when most letters are in place, would be very extremely unlikely?hazel_{March 25, 2009
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hazel, I don't doubt that I'm capable of programming with bugs. I was clear above that I didn't intend to make a point, but to contrast the two approaches. I appreciate that Mr. Elsberry took the time to go through my code and point some things out. However the fRand() bug that Mr. Elsberry highlights doesn't exist when the programs are compiled with MS Visual C++ 2008 Sp1. With reference to the code "if( fRand() < mrate )" Mr. Elsberry writes:
Unfortunately, that will always be true, and every position in every child mutates. A simple check of the convenience function would have revealed this.
I did check the macro to assure the returned values were in the range of [0, 1). Here are a few samples: 0.14032 0.159851 0.766693 0.795013 0.127777 0.483246 0.0346985 0.989258 0.41156 I just now ran a few trials to test the proportion of true results for the expression to the total number of comparisons. 76401/1540000 = 0.0497 27158/560000 = 0.0485 303120/607600 = 0.0499 110410/2212000 = 0.0499 45694/924000 = 0.0495 The actual rate is a little low, but reasonably close to the specified 0.05 rate. The macro is defined this way: #define fRand() (float)rand() / (RAND_MAX + 1) Here is a code snippet from the MSDN documentation for rand() usage: (double)rand() / (RAND_MAX + 1) I'll post on the second reference when I get it sorted.Apollos_{March 25, 2009
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Oops, here's the previous post, correctly formatted kairosfocus quotes Apollos' results, and comments,
A further note is the cluster of reversions captured in the proximity example just above: Gen 600: meuainks it is like a weasel fit: 92% Gen 700: methinks it isrlike a wejrel fit: 89% Gen 800: methsnkr it is tike a weasel fit: 89% Gen 900: methineswit ts likeaa wequel fit: 78% Observe, here, the overt instability of multiple letters and spaces, and how that is easily captured in a skipped-generation sample. This tends to reinforce the point that in Weasel 1986, the observed o/p latching pattern is real, not a mere artifact of sampling.
But just a little bit of thought should show that something is wrong with Apollos' results. If the mutation rate = 5%, then 95% of the time a letter doesn't mutate. At Gen 600 92% of the letters are correct, so only about 8% x 28 = 2 letters are still unmatched. The chances of both of those not mutating is 95%^2 = 90%. If there is no mutation, the child is identical to the parent. so if even one child has no mutations, there is no way the best child can be less fit than the parent. Since the chances of there being a mutation in a child is 100% - 90% = 10%, the chance of all 500 children having a mutation would be 10% ^ 500 = 10 ^ -500, which all us us would consider impossibly low. So the reversions in Apollos' results must be the result of an error of some kind in the implementation of his code.hazel_{March 25, 2009
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kairosfocus quotes Apollos' results, and comments,
A further note is the cluster of reversions captured in the proximity example just above: Gen 600: meuainks it is like a weasel fit: 92% Gen 700: methinks it isrlike a wejrel fit: 89% Gen 800: methsnkr it is tike a weasel fit: 89% Gen 900: methineswit ts likeaa wequel fit: 78% Observe, here, the overt instability of multiple letters and spaces, and how that is easily captured in a skipped-generation sample. This tends to reinforce the point that in Weasel 1986, the observed o/p latching pattern is real, not a mere artifact of sampling.
But just a little bit of thought should show that something is wrong with Apollos' results. If the mutation rate = 5%, then 95% of the time a letter doesn't mutate. At Gen 600 92% of the letters are correct, so only about 8% x 28 = 2 letters are still unmatched. The chances of both of those not mutating is 95%^2 = 90%. If there is no mutation, the child is identical to the parent. so if even one child has no mutations, there is no way the best child can be less fit than the parent. Since the chances of there being a mutation in a child is 100% - 90% = 10%, the chance of all 500 children having a mutation would be 10% ^ 500 = 10 ^ -500, which all us us would consider impossibly low. So the reversions in Apollos' results must be the result of an error of some kind in the implementation of his code.
hazel_{March 25, 2009
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FYI: Wesley Elsberry has pointed out some flaws in Apollos program at http://www.antievolution.org/cgi-bin/ikonboard/ikonboard.cgi?act=ST;f=14;t=5735;st=7920#entry140931". Sorry about the link - I can't quite figure out the url syntax. And to Atom@285 - can you clarify: does your Partitioned search algorithm create a set of children every generation, out of which the best is chosen to be the next parent. I am trying to understand this one point. Thanks.hazel_{March 25, 2009
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Sal Gal:
I saw immediately that the fitness of the parent could decrease from one generation to the next.
If you saw that from reading "The Blind Watchmaker" then please present the quote. Or even an example- something.
Don’t you think it’s just a bit silly to analyze something from a pop science book as though it came from a technical monograph?
I think its a bit silly for anti-IDists to jump on an alleged mistake when upon analyzation no mistake was made. The ONLY reason to analyze that silly book is because that silly book was in question. That is how it is done- if there is an issue you resolve it using whatever is at your disposal.
A good teacher, when trying to get across a new concept, does not go into all the details.
A good teacher doesn't mislead. A good teacher makes the new concept clear. I have done quite a bit of teaching. And I know better than to leave ANYTHING to chance. If Dawkins wants us to believe we can fill a tub full of water if we can spill all the water before reaching the tub he should NOT use a loaded word like "cumulative".Joseph_{March 25, 2009
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Your point about the flaw in locking is very good, as well as the whole post. I've appreciated what you've contributed to this conversation - I'm learning a lot.hazel_{March 25, 2009
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Joseph says,
The way DAWKINS describes and illustrates CUMULATIVE selectioin there isn’t anything that would lead anyone to infer that regression takes place.
I saw immediately that the fitness of the parent could decrease from one generation to the next. You should say that it is not evident to the general reader. Don't you think it's just a bit silly to analyze something from a pop science book as though it came from a technical monograph? (But if you don't have the wherewithal to read technical monographs, I suppose you can keep putting on a show for the "onlookers" by propping up the straw man and knocking him over.) How much teaching have you done, Joseph? A good teacher, when trying to get across a new concept, does not go into all the details. How satisfying is it for you to hear now that, although the fitness of the parent is not strictly increasing, the probability of termination of the program is strictly increasing in the number of generations? The probability of termination approaches 1 as the number of generations goes to infinity. I'll bet that gives you a warm feeling, deep inside. By the way, do you understand that "locking" amounts to teleological suspension of the Second Law of Thermodynamics? That is, errors in genetic transcription are ensured by the Second Law. If you lock in certain letters, you are saying that SLoT is suspended for them, but not for the others. Furthermore, "locking" contradicts a key point of "Darwinian dogma," which Dawkins presents in the book, that mutation is neutral with respect to fitness. What "locking" really explains is Dembski's idée fixe that everyone applying evolutionary algorithms "smuggles in" information. He's so sure he'll see a crime that he's blind to his own misunderstanding. He had absolutely no business pinning "partitioned search" on Dawkins.Sal Gal_{March 25, 2009
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I have accumulated a certain amount of money in my savings account. Does that mean I have never had a moment when my savings account had less money than it did the day before? :-)hazel_{March 25, 2009
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hazel:
When you climb a mountain, you occasionally go downhill before going up again.
And I bet they don't refer to such a process as "cumulative climbing".
Just because you have an occasional reversal doesn’t mean you aren’t accumulating fitness in respect to the target.
And reversal is the opposite of accumulation.Joseph_{March 25, 2009
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hazel:
When you climb a mountain, you occasionally go downhill before going up again. Just because you have an occasional reversal doesn’t mean you aren’t accumulating fitness in respect to the target.
And sometimes you never make it to the top. Also Dawkins should have made it CLEAR that CUMULATIVE selection is really yo-yo selection. The way DAWKINS describes and illustrates CUMULATIVE selectioin there isn't anything that would lead anyone to infer that regression takes place. As a matter of fact the only inference one can come away with is that cumulative selection is a ratcheting process that does nopt allow regression.Joseph_{March 25, 2009
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My apology on a formatting error, etc.kairosfocus_{March 25, 2009
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PS: Now, re Sev @ 273: On a matter that is distasteful but important to cirrect the tendency of seelctive hyperskepticism using ad hominems that divert the thread adn poison its atmosphere. Citing:
On the other issue of the article by Ian Boyne let me reiterate that it was cited only to illustrate that kairosfocus proper name could easily be found in the media. I did not read the article in detail. I got the impression that it was something to do with Christianity but no really much more than that.
Severski, you cited an extract that was condescendingly personally abusive and dismissive, in 148 above. That is obvious to anyone who can read English and understand it. This example, as I recall, was also much bounced about at Anti Evo in recent weeks, on their taking note of me; specifically to try to dismiss what I have to say by attacking me as a person. (Which speaks volumes on mentality as revealed by behaviour, and the quality -- or want of it -- of the case being made at that site.) So, the idea that you "only" cited to show that my name was accessible on the net -- which has never been at issue [Onlookers: I have pointed out that there is a BIG difference between what can be searched out in low traffic corners of the Net and what is being trumpeted in high traffic sites; and that in a context of ad hominems] -- simply does not pass the smell test. FYI, yet again, I have contact information up so that responsible individuals may communicate with me. This information is in a low traffic corner of the Internet, but one that has enough traffic to do what I need to do. Some of that information is also accessible in archival Internet pages in various locations, which are similarly low traffic. When my name appears in the high traffic 'net, that tends to surge my spam inbox and some often breaks through to my main mail box. So, I have used the common Internet civility rule that allows one to have a handle, to buffer my inbox. That you and others choose to disrespect that privacy and courtesy, is telling. Worse,as ntoed, the example you chose is not innocuous, not by a long shot. But, there is a patently obvious duty of care regarding accuracy, context and balance in making adverse comments. So, I am entirely in order to note on the context and content of the criticism made by Mr Boyne, complete with the fact that the Gleaner -- which is not exactly going to be a high traffic web site on archived stories -- was forced to publish a corrective by the undersigned. In particular:
1 --> Mr Boyne was propagating a now all too common blood slander that targets Bible-believing Christians, even going so far as to speculate on how such could easily find Bible verses "enough" to use to justify "butcher[ing]" those who differ from them, while making direct comparisons between Islamist terrorists and Bible believing Christians as enemies of liberty. Even when he tried to deny making an immoral equivalency claim like that, he gave a further example: "[Evangelicals in Jamaica etc are] prone to bigotry, intolerance and the desire to impose their will on others just as the Islamic militants." [Kindly note that telling "JUST AS."] 2 --> Particular, published examples of the "liberty" that Christians in Jamaica were said to object to were [immodest] dress and the dancehall subculture. (At the general time in question, there was a rash of court cases over onstage lewdness, including "cr_tch patting" [a euphemism!] and "dry h_mping" of patrons at shows. Methinks that is libertinism and/or license or licentiousness, not liberty! Can you understand the crucial difference? And, why there is a need for a protected public space where we can reasonably be assured that especially children will not be subjected to such lewd conduct? I hardly need to point out that dignified protest through letters to the editor bears no material comparison to suicide bombing or honour killings or to videotaped beheadings of kidnapped civilians. Mr Boyne's examples and alleged parallels to Islamist militants were utterly out of order; to the point of being outright blood slander.) 3 --> Then, when he tried to dismiss me as making an ill-informed, unwarranted inference from biblical theology to conduct, he was of course gliding over certain inconvenient points that were highlighted in the PRE-sponse:
[BOYNE:} "The world is a much safer place today because the totalitarian ideology of the Christian Crusaders and the Roman Church was decisively routed by the secular state". [GEM of TKI:] . . . Nor is he addressing the vast gap between the biblically illiterate, Christianity of the Middle Ages and the world that resulted from having the reformation sola scriptura principle joined to putting the Bible in the hands of the ordinary man: liberation.
4 --> That is, even through the bad Gleaner editing at work, you can see that I was pointing to the implications of biblical illiteracy for much of the horrors of the Middle Ages [including among the CLERGY!], the corrective put up by the Biblically based Reformation [starting with Luther's 95 theses of intended debate, which were motivated by Tetzel's abuses and evident Simony over indulgences to help fund church building programmes in Rome; which have no biblical warrant] and, most importantly, the historically vital contrasting fact that the absolutist state of the early modern era was in significant part opposed by the Bible-armed ordinary man in the context of a reformation led by theologians of the ilk of a Samuel Rutherford, whose Lex Rex is a classic of opposition to such tyranny; indeed, when it came out King Charles I was heard to remark that it would hardly get an answer. And, nearly fifteen years on, after the execution of Charles I, the book was burned by the public hangman in Edinburgh, and Rutherford only escaped a treason trial by "inconveniently" dying first. Indeed, his reply to those who came to fetch him was a classic, Biblically based rebuke to corrupt officaldom! (Cf the specific response to Mr Boyne the Gleaner elected not to publish.) But in the end, the Bible-rooted ideas in Lex Rex, and further developed by Locke in his essays on civil government [which are also explicitly shaped by biblical insights at key turns in the argument], were a key step in the rise of modern liberty and democracy. (Cf my discussion here.) 5 --> In short, Mr Boyne -- a singularly well informed commenter on public affairs -- was using dismissive mocking rhetoric to glide over facts inconvenient to his case. Facts that show that Bible-rooted thought and action had a lot to do with the rise of modern liberty and democracy. Facts that underscore that Bible believing Christians today are not to be broad-brush dismissed as being morally equivalent to Islamist militants. 6 --> Not to mention, we have just passed through a century in which the secularist state has killed in excess of 100 millions. (Vox Day's contrast to the track erecord of Christendom's princes in a now bygone era is interestng. On average, your C20 secularist tyrant was odds on likely to be responsible for over 20,000 unjustifiable deaths. The typical prince of the era of vanished Christendom, was far, far less luilely to be bloody, over a far longer run.) In that context, the fact that you chose to excerpt and use such claims, in such a context, to try to dismiss my concerns on basic Internet civility, tells us a lot, sir. A lot. Cho, man, do betta dan dat! PLEASE. GEM of TKI
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