leadership in flocks
Locked
 
|
A thoroughly neat synchronicity in the current research on flocking.
Here's some science: http://www.nature.com/nature/journal/v464/n7290/full/nature08891.html (populist version here)
And here's some fluff: http://jasss.soc.surrey.ac.uk/13/2/8.html They come up with distinctly different conclusions. Guess which one I trust.
-- R
============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
Re: leadership in flocks
|
|
Although I tend to agree with you because I think validation and trust are synonyms, I think it's too easy to cherry pick conclusions from either article and say that their research is evidence for those conclusions. The Nagy article merely gives evidence that particular birds may well lead flocks, in general. (But remember that not all flocks are the same. These are expert racing pigeons, after all. ;-) But it doesn't demonstrate that flocking _always_ requires particular leaders. It's sufficient but perhaps not necessary. And although the Quera article has validation problems, it might still be taken for rhetorical evidence supporting the idea that, in some (real world) flocks, perhaps leadership is emergent. I.e. it is _possible_ that (real world) flocking doesn't require particular leaders. As Sarbajit was saying, any single research effort gives us only a tiny, flawed, aspect of reality. So, while I also trust the data-based modeling done by Nagy et al more, I wouldn't denigrate Quera et al as pure fluff. I also wouldn't convict myself to only trusting data-based rhetoric and disbelieving model-based rhetoric. But, obviously, that's me. [grin] Robert Holmes wrote circa 10-04-07 06:17 PM: > A thoroughly neat synchronicity in the current research on flocking. > > Here's some > science: http://www.nature.com/nature/journal/v464/n7290/full/nature08891.html (populist > version here > <http://www.npr.org/templates/story/story.php?storyId=125665334>) > > And here's some fluff: http://jasss.soc.surrey.ac.uk/13/2/8.html > > They come up with distinctly different conclusions. Guess which one I trust. -- glen e. p. ropella, 971-222-9095, http://agent-based-modeling.com ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
Re: leadership in flocks
|
|
The religious grouping I belong to had cause to study/discuss this about 150 years back (concerning flocks of men not birds). The leader of the faction in opposition to mine (which means my faction vehemently disagrees with his view) had this to say
Source: http://books.google.com/books?id=6NkvMc41_0cC& Title: "Great Men ..." (1868) (pg.8) Author : Keshub Chandra Sen "Great men are sent by Grod into the world to benefit mankind. They are His apostles and missionaries, who bring to us glad tidings from heaven ; and in order that they may effectually accomplish their errands they are endowed by Him with requisite power and talents. They are created with a nature superior to that of others, which is at once the testimonial of their apostleship and the guarantee of their success. They are not made great by culture or experience : they are born great. They are ordained and sanctified as prophets at their birth. They succeed, not because of any ability acquired through personal exertions, nor of any favorable combination of outward circumstances, but by reason of their inherent greatness. It is God's light that makes them shine, and enables them to illumine the world. He puts in their very constitution something that is super-human and divine ; hence their greatness and superiority. They are great on account of the large measure of divine spirit which they possess and manifest. It is true they are men, but who will deny that they are above ordinary humanity ? Though human, they are divine. This is the striking peculiarity of all great men. In them we see a strange and mysterious combination of the human and divine nature, of the earthly and the heavenly. It is easy to distinguish a great man, but it is difficult to comprehend him. A deep mystery hangs over the root of his life : the essence of his being is an inexplicable riddle. Who can solve it ? That some nations have carried their reverence for prophets so far as to deify them, and worship them as God, or rather God in human shape, does not in the least appear to me surprising or unaccountable, however guilty they may be of man-worship. For if a prophet is not God, is he a mere man ? That cannot be. Such an hypothesis would not adequately explain all the problems of his life. The fact is, as I have already said, he is both divine and human ; he is both God and man. He is a "God-man". " On Thu, Apr 8, 2010 at 10:43 PM, glen e. p. ropella <[hidden email]> wrote:
============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
Re: leadership in flocks
|
|
sarbajit roy wrote circa 10-04-09 06:34 AM:
> The religious grouping I belong to had cause to study/discuss this about 150 > years back (concerning flocks of men not birds). The leader of the faction > in opposition to mine (which means my faction vehemently disagrees with his > view) had this to say That quote from your opposition seems to fall in line with the nature article, the idea that particular birds/humans (presumably with particular traits, inbred or learned) turn out to be leaders. I take it from your statement that you agree more with the jasss article, that leaders with no particularly exceptional traits emerge? Right? Of course, to even have this discussion, we have to allow ourselves the metaphor between human cliques and bird flocks... -- glen e. p. ropella, 971-222-9095, http://agent-based-modeling.com ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
|
|
Of course, one significant difference between bird flocking behavior and human religious flocking behavior is that birds have brains...
--Doug
On Fri, Apr 9, 2010 at 6:57 PM, glen e. p. ropella <[hidden email]> wrote:
sarbajit roy wrote circa 10-04-09 06:34 AM: ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
|
|
In reply to this post by glen e. p. ropella-2
I haven't read the papers all the way through, but on first blush, I don't see them as contradictory. Either could be correct.
A "leader" - whether bird or person - could act first due to internal traits (inclination, ability, imagination) or external influence. The first implies that the leader is different from the others in some way, while the second implies only a situational difference: circumstance rather than inherent traits.
Once the leader acts, this creates space for the other birds/people to act similarly, and follow the leader. The followers must have had the same inclination towards this action, because they end up doing it, too ... they just weren't over the tipping point yet. There was something missing that kept them from acting first. The leader's action clearly provides the missing element, and so all the followers perform the same action.
The remarkable thing about the flocking models, such as the one in JASS, is that they show that leadership doesn't have to be due to an internal trait. It may simply be a situational difference among very similar agents. Before these models were put forth, the prevailing view was that leadership is always endogenous to the leader. Now, at least, we can consider other possibilities, whether or not they end up being correct.
-t
On Fri, Apr 9, 2010 at 8:57 PM, glen e. p. ropella <[hidden email]> wrote: sarbajit roy wrote circa 10-04-09 06:34 AM: ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
|
|
In reply to this post by Robert Holmes
Ted,
Perhaps I havent been following this thread closely enough to put my oar in, but the following passage caught my eye:
"The remarkable thing about the flocking models, such as the one in JASS, is that they show that leadership doesn't have to be due to an internal trait. It may simply be a situational difference among very similar agents. Before these models were put forth, the prevailing view was that leadership is always endogenous to the leader. Now, at least, we can consider other possibilities, whether or not they end up being correct."
Think about this passage as if the "boids" were cells in a early developing embryo. EVERY cell is exactly the same, yet some become leaders. We will be talking about this next fall in a CUSF seminar on epigenisis.
Nick
Nicholas S. Thompson
Emeritus Professor of Psychology and Ethology,
Clark University ([hidden email])
http://www.cusf.org [City University of Santa Fe]
============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
Re: leadership in flocks
|
|
In reply to this post by Ted Carmichael
How similar to the sperm peloton and the cyclist peloton, now we have flocks with leaders and cliques?.
If each model has a different organizing principle then why does my simple mind think there are similarities?
I liked Hugh Trenchard’s ideas the best, there was no need for more than a simple available power assessment on the part of the individual agent. Sticking the term leadership into the discussion really puts a strange twist to everything.
Trenchard’s ideas would have probably worked for the flocks equally well, and that is truly interesting. Craig Reynolds 1982? wrote his early “Boids “ paper with only very simple principles none of which included power or aerodynamics.
Same organized behavior but completely different principles. Do we force complex interpretations where simple ones suffice.
A “leader” in a cycling peloton is such a temporary phenomenon that one has to be very careful how the term it is used. But in the bird flock the leader seems to be part of a social dynamic which might not actual exist but in the minds of the writers?
Inventing complex explanations for simple situations seems similar to what conspiracy theorists practice.
Dr.Vladimyr Ivan Burachynsky Ph.D.(Civil Eng.), M.Sc.(Mech.Eng.), M.Sc.(Biology)
120-1053 Beaverhill Blvd. Winnipeg, Manitoba CANADA R2J 3R2 (204) 2548321 Phone/Fax
-----Original Message-----
I haven't read the papers all the way through, but on first blush, I don't see them as contradictory. Either could be correct.
A "leader" - whether bird or person - could act first due to internal traits (inclination, ability, imagination) or external influence. The first implies that the leader is different from the others in some way, while the second implies only a situational difference: circumstance rather than inherent traits.
Once the leader acts, this creates space for the other birds/people to act similarly, and follow the leader. The followers must have had the same inclination towards this action, because they end up doing it, too ... they just weren't over the tipping point yet. There was something missing that kept them from acting first. The leader's action clearly provides the missing element, and so all the followers perform the same action.
The remarkable thing about the flocking models, such as the one in JASS, is that they show that leadership doesn't have to be due to an internal trait. It may simply be a situational difference among very similar agents. Before these models were put forth, the prevailing view was that leadership is always endogenous to the leader. Now, at least, we can consider other possibilities, whether or not they end up being correct.
-t On Fri, Apr 9, 2010 at 8:57 PM, glen e. p. ropella <[hidden email]> wrote: sarbajit roy wrote circa 10-04-09 06:34 AM: >
The religious grouping I belong to had cause to study/discuss this about 150 That quote from your
opposition seems to fall in line with the nature glen e. p. ropella,
971-222-9095, http://agent-based-modeling.com
============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
|
|
In reply to this post by Ted Carmichael
Merle Lefkoff wrote:
Regardless of whether leaders act because of endogenous traits or a circumstantial opening, they are indeed emergent throughout the system. In human systems, however, unlike flocks, over-determined structures suppress this emergent property of the system. Rather than stepping aside to allow emerging leaders to bring requisite variety to the "flock", elite hierarchies/patriarchies suppress distributed leadership and generally prevail for long periods of time. Ted Carmichael wrote: > I haven't read the papers all the way through, but on first blush, I > don't see them as contradictory. Either could be correct. > > A "leader" - whether bird or person - could act first due to internal > traits (inclination, ability, imagination) or external influence. The > first implies that the leader is different from the others in some > way, while the second implies only a situational difference: > circumstance rather than inherent traits. > > Once the leader acts, this creates space for the other birds/people to > act similarly, and follow the leader. The followers must have had the > same inclination towards this action, because they end up doing it, > too ... they just weren't over the tipping point yet. There was > something missing that kept them from acting first. The leader's > action clearly provides the missing element, and so all the followers > perform the same action. > > The remarkable thing about the flocking models, such as the one in > JASS, is that they show that leadership doesn't have to be due to an > internal trait. It may simply be a situational difference among very > similar agents. Before these models were put forth, the prevailing > view was that leadership is always endogenous to the leader. Now, at > least, we can consider other possibilities, whether or not they end up > being correct. > > -t > > On Fri, Apr 9, 2010 at 8:57 PM, glen e. p. ropella > <[hidden email] <mailto:[hidden email]>> > wrote: > > sarbajit roy wrote circa 10-04-09 06:34 AM: > > The religious grouping I belong to had cause to study/discuss > this about 150 > > years back (concerning flocks of men not birds). The leader of > the faction > > in opposition to mine (which means my faction vehemently > disagrees with his > > view) had this to say > > That quote from your opposition seems to fall in line with the nature > article, the idea that particular birds/humans (presumably with > particular traits, inbred or learned) turn out to be leaders. I > take it > from your statement that you agree more with the jasss article, that > leaders with no particularly exceptional traits emerge? Right? > > Of course, to even have this discussion, we have to allow > ourselves the > metaphor between human cliques and bird flocks... > > -- > glen e. p. ropella, 971-222-9095, http://agent-based-modeling.com > > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's College > lectures, archives, unsubscribe, maps at http://www.friam.org > > > ------------------------------------------------------------------------ > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's College > lectures, archives, unsubscribe, maps at http://www.friam.org ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
Re: leadership in flocks
|
|
Wow, wait a second,
If the object in motion has a group of followers I don't see emergence, Remoras follow sharks or any other moving object, there is no dynamic social system. My Wolfhounds follow rabbits, horses, snowmobiles, bicycles etc at very high speeds. If they were displayed on a radar screen you might mistake five wolfhounds as worshipful devotees of a single leader, running in absolute terror. If they all came to a stop on the radar screen you might surmise the group fell into disarray as the result of a leadership dispute. Perhaps one might think there was a socially repressive regime at work when the blips resolved as five instead of six, and the pace slowed down. "Merle Lefkoff wrote: Regardless of whether leaders act because of endogenous traits or a circumstantial opening, they are indeed emergent throughout the system. In human systems, however, unlike flocks, over-determined structures suppress this emergent property of the system. Rather than stepping aside to allow emerging leaders to bring requisite variety to the "flock", elite hierarchies/patriarchies suppress distributed leadership and generally prevail for long periods of time." It looks like the first sign of legitimate "emergence" is the Hierarchy that perceives the front man as a leader and attempts later to suppress it, whether it is a leader or not makes no difference. The act of suppression emerges complete based on its own belief system. The belief system must have been in place prior to the flock being created, the leader was accidental (Circumstantial) but suppression is truly emergent, or is it? Are we not talking about completely different behaviors and only one of them is truly emergent? Am I just new to the wording, or am I missing something? Dr.Vladimyr Ivan Burachynsky Ph.D.(Civil Eng.), M.Sc.(Mech.Eng.), M.Sc.(Biology) 120-1053 Beaverhill Blvd. Winnipeg, Manitoba CANADA R2J 3R2 (204) 2548321 Phone/Fax [hidden email] -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of Merle Lefkoff Sent: April 10, 2010 12:31 PM To: The Friday Morning Applied Complexity Coffee Group Subject: Re: [FRIAM] leadership in flocks Merle Lefkoff wrote: Regardless of whether leaders act because of endogenous traits or a circumstantial opening, they are indeed emergent throughout the system. In human systems, however, unlike flocks, over-determined structures suppress this emergent property of the system. Rather than stepping aside to allow emerging leaders to bring requisite variety to the "flock", elite hierarchies/patriarchies suppress distributed leadership and generally prevail for long periods of time. Ted Carmichael wrote: > I haven't read the papers all the way through, but on first blush, I > don't see them as contradictory. Either could be correct. > > A "leader" - whether bird or person - could act first due to internal > traits (inclination, ability, imagination) or external influence. The > first implies that the leader is different from the others in some > way, while the second implies only a situational difference: > circumstance rather than inherent traits. > > Once the leader acts, this creates space for the other birds/people to > act similarly, and follow the leader. The followers must have had the > same inclination towards this action, because they end up doing it, > too ... they just weren't over the tipping point yet. There was > something missing that kept them from acting first. The leader's > action clearly provides the missing element, and so all the followers > perform the same action. > > The remarkable thing about the flocking models, such as the one in > JASS, is that they show that leadership doesn't have to be due to an > internal trait. It may simply be a situational difference among very > similar agents. Before these models were put forth, the prevailing > view was that leadership is always endogenous to the leader. Now, at > least, we can consider other possibilities, whether or not they end up > being correct. > > -t > > On Fri, Apr 9, 2010 at 8:57 PM, glen e. p. ropella > <[hidden email] <mailto:[hidden email]>> > wrote: > > sarbajit roy wrote circa 10-04-09 06:34 AM: > > The religious grouping I belong to had cause to study/discuss > this about 150 > > years back (concerning flocks of men not birds). The leader of > the faction > > in opposition to mine (which means my faction vehemently > disagrees with his > > view) had this to say > > That quote from your opposition seems to fall in line with the nature > article, the idea that particular birds/humans (presumably with > particular traits, inbred or learned) turn out to be leaders. I > take it > from your statement that you agree more with the jasss article, that > leaders with no particularly exceptional traits emerge? Right? > > Of course, to even have this discussion, we have to allow > ourselves the > metaphor between human cliques and bird flocks... > > -- > glen e. p. ropella, 971-222-9095, http://agent-based-modeling.com > > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's College > lectures, archives, unsubscribe, maps at http://www.friam.org > > > ------------------------------------------------------------------------ > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's College > lectures, archives, unsubscribe, maps at http://www.friam.org ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
|
|
In reply to this post by Vladimyr Burachynsky
Vladimyr -
I agree strongly with this point. I think scientists (maybe especially those working in complexity?) are as prone as "civilians" to projection in their observations of natural phenomena. We see a "lead bird" and assume that the bird is "leading". A cynical variation on this in human populations (especially in Dilbereetaville) is the observation that many of our leaders are really like a "band leader" who sees the parade and jumps out in front of it waving his/her baton. Merle - Rather than stepping aside to allow emerging leaders to bring requisite variety to the "flock", elite hierarchies/patriarchies suppress distributed leadership and generally prevail for long periods of time. I am not inclined to disagree that this happens (all too frequently) but I wonder at the assumption in the first phrase "rather than stepping aside". It suggests that any leader is interested in the health of the flock/herd/tribe/state. I don't think that herd and pack animals' leaders act much differently than human leaders in this case. They seem to be driven by instinct to maintain dominance over the group, often defending that dominance unto death. It is their instincts to dominate and survive that leads the pack/herd to survival. An active form of metonymy where he group inherits (some of) the characteristics of the leader. Do we believe that humans are truly unique in this trait? It seems to me that "leadership" in all animals is emergent and a consequence of local forces (the individual urge to be dominant, almost exclusively among males, at least among mammals). Humans have the latent possibility for something more altruistic/noble perhaps... but it is the failure to rise to such altruism/nobility rather than a degeneracy away from what is "natural" for herd/pack mammals? I was just reading John Searle's mind language and society where he makes the case that only humans have a significant grasp on causality. This suggests to me that non-human "leaders" are leading circumstantially, instinctively, emergently and are "selected" the same way. It is *only* in humans that we see any significant deviation from this toward altruism... and that often seems only to be apparent, rather than real. Do we have true leaders/statesmen or do we merely have politicians who know how to pose as the former? I also accede that many cultures have managed to enhance the hierarchy/patriarchy (why are matriarchies never impugned by attribution of these traits?) into dysfunctional caricatures (albeit ones that often span generations and huge regions). I've ranted here before about "Homo Hiveus" and will indulge in a brief revisit of that rant. I very much want to attribute a lot of human's collective "bad behaviour" on acting completely out of the scale we were evolved for. If we evolved in family groups of 100-200 among clans of perhaps thousands in ethnic/language groups of perhaps tens of thousands, how in the world do we expect even cities of millions to make sense much less a world with billions. We are evolved to make decisions based on family and trust networks with dozens of others, not millions and billions. Our artificial social/economic/religious constructs of church/currency/state have allowed us to operate outside of these natural scales but at what cost? As an often-maligned male, I take exception to the general assumption that the problems of abusive/runaway hierarchy are a male-only trait. Power Corrupts. Period. On Venus as well as on Mars. Do we have any evidence that women do better at "leading" totally out-of-scale societies than men? If there is any (anecdotal?) evidence in support of Matriarchy, it might be that Matriarchies don't seem to grow out of control the way the Patriarchies in evidence have? - Steve ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
|
|
In reply to this post by Vladimyr Burachynsky
Comments below...
On Sat, Apr 10, 2010 at 3:07 PM, Vladimyr Ivan Burachynsky <[hidden email]> wrote: Wow, wait a second, Emergence is a tough concept. My understanding is, an emergent property requires correlated feedback in the system. A pack of dogs following a single rabbit, say - with the rabbit's actions influencing the dogs, and the dogs' actions influencing each other - may display emergent properties. For example, in an open, flat field, the rabbit may be more likely to run in a straight line, with individual dogs occasionally keeping the rabbit from diverging to the left or the right. The straight line would be the emergent property. The dogs are both trying to catch the rabbit and avoid crashing into other dogs, producing a "flock" of dogs.
I'm not sure I would label 'suppression' as emergent. Depends on exactly what you are referring to. Perhaps a better label is "feedback?" What's interesting about the leadership hierarchies, in human systems, is that the structures themselves are an emergent property. Persistent patterns, changing components. The leadership hierarchy becomes a "basin of attraction," with it's own support structures and correlated feedbacks, even as the people within the hierarchy change over time.
-t
============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
|
|
But by your own definition, an emergent property requires correlated feedback in the system
supression is as likely to emerge as leadership, and thus we revert to the question in earlier conversations about the value systems of the observer fabricating the label of emergent or not. Right? Or, seconding Dr B, am I just not used to your terminology? Certainly am enjoying this. Tory On Apr 10, 2010, at 2:41 PM, Ted Carmichael wrote: Comments below... ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
|
|
No, it's a good question, Tory. I said I wasn't sure about the label "emergent" being applied to suppression, and I'm not. Thinking about it more, it's a good idea to clarify the terminology.
Let's see ... a single act of suppression is feedback that helps to preserve the emergent feature of a leadership hierarchy. A single action is not emergent (at least, in this scope). But I'll have to agree that the term "suppression" could easily represent correlated feedback among many agents, and is thus also an emergent feature. I guess I was just thinking of suppression as part of the leadership "basin of attraction."
I mean, it's the same thing from a different perspective, isn't it? Kind of like: do you call mud "dirty water," or "wet dirt?" The water is part of it, the dirt is part of it, but it's easier to just call the whole thing "mud." In this case, the leadership hierarchy persists, the correlated feedback is part of it, and it's all emergent.
So, I reckon we're talking about the same thing. In regards to the observer's value system, I would say that traditionally, we tended to view things like slime mold and ant colonies through the prism of human hierarchical systems. Keller, and Segal showed that - in the case of slime mold - a distinct "pacemaker" cell (i.e., a leader) was not necessary to produce the emergent property. This helped a lot, since the pacemaker cells had never been found.
But certainly I would agree that our observations and value judgement may be flawed. I think that is the benefit of this whole field of study: we no longer have to rely on a single model of hierarchical structures. We now have distributed models that can also work, and we simply select whichever model fits best.
I, too, am enjoying this conversation. -T On Sat, Apr 10, 2010 at 4:49 PM, Victoria Hughes <[hidden email]> wrote:
============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
|
|
Correlated feedback? The example given is that of a pack of dogs chasing a rabbit and keeping it running in a straight line. The straight line is the emergent property. A similar example is a thermostat -- or a bunch of thermostats distributed around an area. (If you like they can control independently operating heating sources.) The emergent property is that the temperature remains within a given range. But what about static examples, e.g., chlorine and sodium combining to produce salt or carbon atoms put together to create a diamond? Would you want to dismiss these as emergent -- or find a way to think of them in terms of correlated feedback?
Part of the problem I'm having with correlated feedback is that it seems, perhaps, correlated with emergence but neither necessary nor sufficient. As an example where it's not sufficient how about the grades of students taking a nationwide test, e.g., the SAT. This is feedback, and there are certainly correlations, but I'm not sure what the emergent property is. It might be a teach-(or study)-to-the-test phenomenon. But then we seem to be saying that virtually anything that exhibits correlated feedback is emergent by definition. Looking a bit more closely, feedback implies an agent that is has some control over its actions and that makes decisions about those actions on the basis of some feedback. So a market, for example, has lots of correlated feedback. People buy or sell more or less depending on the current price, which itself varies with the actions of the participants. Generalizing from that example, one would then have to say that any collection of interacting agents whose actions depend in part on the actions of the other agents produces emergence. Perhaps. But it doesn't seem to be telling me much to say that. Worse, it doesn't give me any means to determine what the emergent phenomenon is. It may look like chaos. But then perhaps you will want to say that the chaos is an emergent phenomenon--as in the response to shouting FIRE in a crowed theater. Lots of correlated feedback resulting in the emergence of chaos. -- Russ Abbott ______________________________________ Professor, Computer Science California State University, Los Angeles cell: 310-621-3805 blog: http://russabbott.blogspot.com/ vita: http://sites.google.com/site/russabbott/ ______________________________________ On Sat, Apr 10, 2010 at 7:10 PM, Ted Carmichael <[hidden email]> wrote: No, it's a good question, Tory. I said I wasn't sure about the label "emergent" being applied to suppression, and I'm not. Thinking about it more, it's a good idea to clarify the terminology. ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
|
|
Well, I don't know if the feedback is sufficient to produce emergence, but I would guess that it is necessary, particularly in a complex system.
In regards to the SAT, aren't the grades the emergent property? Basically, we get a bell-curve around a mean score ... the bell curve emerges, doesn't it? And as the students learn more about the test, and effective test-taking strategies emerge, the mean rises. It's not perfect, of course, but the feedback definitely represents a force towards an emergent property. And the test itself changes over time, so that the mean tends to be around a certain score, or within a certain range. I think the SAT was 'adjusted' in the 90's, so that the mean was closer to the traditional range.
Static examples are more difficult. But I think it can still work. We talk about the strength of the bond as the emergent property. So ... something has to test that strength, right? And when it does, the molecule resists in a correlated way, preserving (or trying to preserve) the emergent structure.
I guess a counter-example would be a pool table, with - let's say - frictionless balls bouncing around. When one ball strikes another ball, they both change direction; but all the collisions between various balls are not really correlated, and so the system is chaotic, and remains that way. Something else - some sort of correlated force - would have to be introduced into the system to allow for recognizable patterns to emerge.
Part of this is just thinking out loud, as it were. I certainly recognize that there are levels of complexity, and issues of scope, and a lot of it comes down to identifying the interesting patterns. Sometimes it's more art than science, especially in the human systems that have so many more factors to consider.
I wouldn't claim that chaos is an emergent feature, but I also wouldn't necessarily describe a panicked theater as purely chaotic. To the extent that the feedback among the people is correlated in some way - say, towards the exits - then emergent patterns emerge, and the people stream out of those exits. But if by "panic" you mean the feedback isn't really correlated, and the people are crashing into each other, running pell-mell in any direction, then the system is chaotic and emergent streams of people towards the exits don't form. So, I think in that example, the characterization of correlated feedback still works.
-t On Sat, Apr 10, 2010 at 10:42 PM, Russ Abbott <[hidden email]> wrote:
============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
Re: leadership in flocks
|
|
It is possible this is topic going astray, due to my use of language, so let me first apologize.
A troop of a dozen Gaze hounds is a mob, at least from my view point just over 6 feet. Nothing is straight about it, ever. The Jack is a mad pin ball changing vectors as fast as possible in an effort to spread a full 12 dog troop over a dozen acres. It is a strategic game of trying to cause crashes as often as possible until all the players are splayed out. It is a high speed war in 2 sometimes 3 dimensions only rarely does anything like a leader appear. Quite often the Jack is under the tall legged dogs. Sometimes it is actually running across their backs. The Jack uses terrain, the dogs use flat out speed and teeth. Some dogs are smart and use their feet first and try and flip a Jack some will use their tails and swat backwards Jacks are not really rabbits they are Hares and very fast and maneuverable and they do not have to worry about colleagues that weigh in over 100lbs up to 140lbs. This is a chess game with very few rules. No edges except, every mile 1.6 kms. Nobody lives that long. The other parameter is body heat, both sides try and keep the other one moving until it drops dead.
Heat, terrain, teeth, vegetation cover and speed. Balance another factor, stubble also counts, no mountains, no rivers, only open prairie. No rules or judges. There is no flock pattern but for the breifest of moments wind resistance plays little or no part not even a finish line. So this is real life real agents, and it sometimes gets very bloody, mostly dogs get so frustrated they take on one another. That works for the Jack. Now the flock is neat an easily recognozable pattern, you call it emergent I call it a “temporal accident”, between chaotic states. The behavior is certainly complex but I’ll be darned if you will ever see a pattern repeat itself. So this is definitely real life, but where is the emergent behavior?. I know what I think is happening, I saw it many times and yet I never could predict much, except some dogs would end up at the vet’s office and the Jack would get away and humiliate my champions. The explanation is that emergent behavior is not predictable nor is it necessarily recognizable according to Pattee 1987 Artificial Life proceedings Santa Fe. Those neat patterns were not originally accepted as emergence, they were called frozen accidents on page 72. The flock is not emergent behavior but migration definitely fits my concept and seems to meet Pattee’s. But Complexity seems to be the focus not AL so did complexity reduce its scope of interest and did AL just die out? Did Complexity inherit a dead language and try and make it work in a new environment? I suspect that if a pattern is easily recognized it probably is just another bumper sticker. Perhaps everybody is just hunting for the next wowy factor? Back in 87 Complexity waas only one of three components necessary to define emergemce. Now emergence seems to be a feature of complexity.
Patte suggested three components were required for emergent behavior to distinguish Life from simulation, first complexity using terms like non linearity and symmetry breaking, second semantics or symbology I had trouble with that but sometimes it seems like an image or idea ( The Jack recognized teeth and predatory eyes), and lastly some kind of measurement concepts dragging in the Quantum physics issues of observtion( The Jack seemed to anticipate positions and terrain features with incredible precision, he itroduced self awareness Obviously you have to use yourself as part of the frame of reference if you measure ). No one but perhaps Glen Ropella touches on these issues but I may be mistaken. I do occasionally miss threads. But it seems artificial life is a dead issue and all that remains are the cute simulations. So if you think a pack of dogs and a flock have something in common explain it to me one more time and I will try and find a straight line emerging from the dusty prairie. In 1987 it seemed there was general agreement that there were no global controls or rules coordinating the agents so I have been intrigued by agents with inherent rules and nothing much more sophisticated. There are a lot of mistakes made during a hunt that I know full well. So I never frustrated myself with perfection even dinner time is negotiable.
The Hunt was the emergent behavior but as Pattee explained, it might not be definable with conventional tools. As might be waterfowl migration, so do we settle for cute pictures or do we open discussion about what started all this complexity interest down in Santa Fe. It’s your backyard guys, I am so sorry I never travelled down to see the show back then.
I wish I had a video camera back then to show you what a Hunt looks like and compare it to a peloton or a flock. I have my fingers crossed that truly emergent behavior leaves evidence even though it itself may be fleeting or unrecognizable.
I will quote H.H.Pattee again , “ A simulation of life can be very instructive both empirically and theoretically, but we must be explicit about what claims we make for it” He went on to warn readers about the mistakes of the Artificial Intelligence ventures.which ignored the enormous knowledge base of biology.
I tink I have stumbled upon a semiotic swap, the original hierarchy has flipped as more nd more focus is broughtto Computation and Simulaton. I can see how the unrecognizable unknown forms of emergence were problematic and it ws very easy to change te focus to nice stable patterns which used to be called frozen accidents.
The lack of biologists has allowed a cultural realignment to center on the skills of te remaining participants namely programmers. So the semiotic swap must have happened some while ago and the language frustration is still and echo of an older revolution. It seems that the focus on simulations and frozen accidents is exactly what Pattee warned about, the real emergence which was very difficult to conceptualize was replaced by easily recognizable frozen accidents. So did the search for the essence of true emergence, characteristc of Living systems, simply fizzle out? As a former biologist and unofficial code geek I got to see both sides of the quandry and it makes perfect sense that the old ideal was simply unmanageable and a semiotic swap was the only way to save face and keep funding in place.
I guess the conclusion is that Life is long dead and pretty pictures are the new frontier for research. Now that simulations no longer require reference to the living world anything goes and the prettier the better. Maybe a lot of us are caught with one foot on the dock and the other is still In the canoe. Trying to split yourself linguistically semiotically can hurt just as bad, so the living systems of reality are no longer needed for reference and not relevant right?
I got out ito my bush today and shot some Prairie Crocuses still covered in the winter Fur. I always am amazed at these fur clad northern plants. Isn’t evolution marvellous. Water is still frozen but in just the right location there is enough heat to keep life rolling along pushing through frozen soils. The look a lot like a Jack’s tail when the break ito the weak sunlight then they explode into Pale Blue petals bright yellow stamens surrounding a fur clad white pistil . I will have to wait few days to shoot the hardy pollinators Unknown and Unpredictable.(I know I could Google it but heck I like surprises)
Dr.Vladimyr Ivan Burachynsky Ph.D.(Civil Eng.), M.Sc.(Mech.Eng.), M.Sc.(Biology)
120-1053 Beaverhill Blvd. Winnipeg, Manitoba CANADA R2J 3R2 (204) 2548321 Phone/Fax
-----Original Message-----
Well, I don't know if the feedback is sufficient to produce emergence, but I would guess that it is necessary, particularly in a complex system.
In regards to the SAT, aren't the grades the emergent property? Basically, we get a bell-curve around a mean score ... the bell curve emerges, doesn't it? And as the students learn more about the test, and effective test-taking strategies emerge, the mean rises. It's not perfect, of course, but the feedback definitely represents a force towards an emergent property. And the test itself changes over time, so that the mean tends to be around a certain score, or within a certain range. I think the SAT was 'adjusted' in the 90's, so that the mean was closer to the traditional range.
Static examples are more difficult. But I think it can still work. We talk about the strength of the bond as the emergent property. So ... something has to test that strength, right? And when it does, the molecule resists in a correlated way, preserving (or trying to preserve) the emergent structure.
I guess a counter-example would be a pool table, with - let's say - frictionless balls bouncing around. When one ball strikes another ball, they both change direction; but all the collisions between various balls are not really correlated, and so the system is chaotic, and remains that way. Something else - some sort of correlated force - would have to be introduced into the system to allow for recognizable patterns to emerge.
Part of this is just thinking out loud, as it were. I certainly recognize that there are levels of complexity, and issues of scope, and a lot of it comes down to identifying the interesting patterns. Sometimes it's more art than science, especially in the human systems that have so many more factors to consider.
I wouldn't claim that chaos is an emergent feature, but I also wouldn't necessarily describe a panicked theater as purely chaotic. To the extent that the feedback among the people is correlated in some way - say, towards the exits - then emergent patterns emerge, and the people stream out of those exits. But if by "panic" you mean the feedback isn't really correlated, and the people are crashing into each other, running pell-mell in any direction, then the system is chaotic and emergent streams of people towards the exits don't form. So, I think in that example, the characterization of correlated feedback still works.
-t
On Sat, Apr 10, 2010 at 10:42 PM, Russ Abbott <[hidden email]> wrote: Correlated
feedback? The example given is that of a pack of dogs chasing a rabbit
and keeping it running in a straight line. The straight line is the emergent
property. A similar example is a thermostat -- or a bunch of thermostats
distributed around an area. (If you like they can control independently
operating heating sources.) The emergent property is that the temperature
remains within a given range. But what about static examples, e.g., chlorine
and sodium combining to produce salt or carbon atoms put together to create a
diamond? Would you want to dismiss these as emergent -- or find a way to think
of them in terms of correlated feedback?
On Sat, Apr 10, 2010 at 7:10 PM, Ted Carmichael <[hidden email]> wrote: No, it's a good question, Tory. I said I wasn't sure about the label "emergent" being applied to suppression, and I'm not. Thinking about it more, it's a good idea to clarify the terminology.
Let's see ... a single act of suppression is feedback that helps to preserve the emergent feature of a leadership hierarchy. A single action is not emergent (at least, in this scope). But I'll have to agree that the term "suppression" could easily represent correlated feedback among many agents, and is thus also an emergent feature. I guess I was just thinking of suppression as part of the leadership "basin of attraction."
I mean, it's the same thing from a different perspective, isn't it? Kind of like: do you call mud "dirty water," or "wet dirt?" The water is part of it, the dirt is part of it, but it's easier to just call the whole thing "mud." In this case, the leadership hierarchy persists, the correlated feedback is part of it, and it's all emergent.
So, I reckon we're talking about the same thing.
In regards to the observer's value system, I would say that traditionally, we tended to view things like slime mold and ant colonies through the prism of human hierarchical systems. Keller, and Segal showed that - in the case of slime mold - a distinct "pacemaker" cell (i.e., a leader) was not necessary to produce the emergent property. This helped a lot, since the pacemaker cells had never been found.
But certainly I would agree that our observations and value judgement may be flawed. I think that is the benefit of this whole field of study: we no longer have to rely on a single model of hierarchical structures. We now have distributed models that can also work, and we simply select whichever model fits best.
I, too, am enjoying this conversation.
-T On Sat, Apr 10, 2010 at 4:49 PM, Victoria Hughes <[hidden email]> wrote: But by your own definition, an emergent property requires correlated feedback in the system supression is as likely to emerge as leadership, and thus we revert to the question in earlier conversations about the value systems of the observer fabricating the label of emergent or not. Right? Or, seconding Dr B, am I just not used to your terminology?
Certainly am enjoying this.
Tory
On Apr 10, 2010, at 2:41 PM, Ted Carmichael wrote:
============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
Re: leadership in flocks
|
|
In reply to this post by Vladimyr Burachynsky
Vladimyr Ivan Burachynsky wrote circa 10-04-10 10:16 AM:
> Same organized behavior but completely different principles. Do we force > complex interpretations where simple ones suffice. Yes, we definitely _do_ when the validation data indicates that the more complex mechanisms actually exist, as with the nature article. The trouble with parsimony as you're applying it in the above sentence is that you've abstracted out a particular phenomenon and intend to build a model to mimic only that particular phenomenon. This linearization of the system (and model) ignores lots of data regarding other related phenomena. I.e. you're abstracting out a simple (non-complex) phenomena and mimicking it with a simple model. That's not science so much as it's engineering or math. Science has to consider all the available data, even data sets that are incommensurate with each other. This requires concrete models and is why most scientists are intent on designing experiments with the "actual stuff" and only want to use computational models sparingly or in special cases. Simple one's do not suffice in the concrete world of actual flocks of birds. Actual flocks _have_ all the complicating detail and the extent to which that complicating detail can be removed or controlled is very limited. That's why the Nature article is more powerful and meaningful than the JASSS article. -- glen e. p. ropella, 971-222-9095, http://agent-based-modeling.com ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
semiotic swap? (was Re: leadership in flocks)
|
|
In reply to this post by Vladimyr Burachynsky
Vladimyr Ivan Burachynsky wrote circa 10-04-11 05:20 PM:
> But Complexity seems to be the focus > not AL so did complexity reduce its scope of interest and did AL just die > out? Did Complexity inherit a dead language and try and make it work in a > new environment? I suspect that if a pattern is easily recognized it > probably is just another bumper sticker. Perhaps everybody is just hunting > for the next wowy factor? Back in 87 Complexity waas only one of three > components necessary to define emergemce. Now emergence seems to be a > feature of complexity. > > [...] > > I tink I have stumbled upon a semiotic swap, the original hierarchy has > flipped as more nd more focus is broughtto Computation and Simulaton. I can > see how the unrecognizable unknown forms of emergence were problematic and > it ws very easy to change te focus to nice stable patterns which used to be > called frozen accidents. I don't think this is a semiotic swap... or, at least to me, it's not. AL and pretty pictures are part of the general attempt to model what _could_ be in order to understand what _is_. That's what AL is all about and, to a large extent, what every modeling effort is about. One tries to circumscribe and sample the space of possibilities in order to understand the context in which some process obtains. The reason we need these _impoverished_ approaches is because we can't do experiments over the actual systems. We can't recreate N>33 solar systems to experiment on the origins and evolution of the biosphere. [grin] So, we have to do it all virtually and define validation touch points. But, without the validation, it's largely useless. (I know everyone knows this... but it sometimes helps to repeat it.) Complexity studies encompass both artificial systems (what could be) and real systems (what is). > The lack of biologists has allowed a cultural realignment to center on the > skills of te remaining participants namely programmers. So the semiotic swap > must have happened some while ago and the language frustration is still and > echo of an older revolution. It seems that the focus on simulations and > frozen accidents is exactly what Pattee warned about, the real emergence > which was very difficult to conceptualize was replaced by easily > recognizable frozen accidents. So did the search for the essence of true > emergence, characteristc of Living systems, simply fizzle out? As a former > biologist and unofficial code geek I got to see both sides of the quandry > and it makes perfect sense that the old ideal was simply unmanageable and a > semiotic swap was the only way to save face and keep funding in place. Yes, this list is certainly dominated by computer people, to its great loss and gain. But I think most of the people on the list sporadically (or usually) realize this and appreciate input from the other domains. The trouble is that the languages and styles used by math/computer people is forceful and precise, leading to a form of intimidation. It doesn't allow so much for "fluffy" stuff (like the offal I often foist onto the list), though a few people would say that the list is dominated by fluffy stuff. [grin] However, we do find some compensation for that intimidation in the form of overt welcoming of ill-formed rhetoric. But I doubt many of the people on the list, even the ones guilty of taking incredible license with various words and concepts, are totally ignorant of the multiple meanings (ambiguity) behind words like emergence. That's why we keep coming back to these concepts, seemingly to no avail, because we're trying to anneal into a stable, interdisciplinary, semantics. That we do flip around from one to another aspect of things like emergence, ontology, epistemology, the meaning of math, etc. is evidence of that attempt to anneal. That's what I think, anyway. -- glen e. p. ropella, 971-222-9095, http://tempusdictum.com -- glen e. p. ropella, 971-222-9095, http://agent-based-modeling.com ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
Re: peloton/ leadership in flocks
|
|
In reply to this post by Vladimyr Burachynsky
Just as an update and a follow up note on the
cyclist/sperm aggregations, I've developed (and am continuing to
develop) a simple computer peloton simulation and am working through a
series of experiments. Aspects of the simulation apply to certain
sperm aggregates as well (at least I will suggest this).
The plan at this point if for the the sim to
involve these sets of experiments:
1. a "no drafting" set where two or more sets
of agents proceed according to their own intrinsic max sustainable speed with no
capacity to match the speed of agents of other sets;
2. a "weak drafting" set, where weaker
agents can match the speeds of others if in a certain proximity
of faster agents;
3. a "strong" drafting set where agents
actually seek to match speeds of others by following behind others.
I've completed a set of experiments for number 1,
which is the obvious case in which group sorting occurs according
to maximum sustainable output, and the easiest to simulate.
The others are still underway.
My aim is to demonstrate that:
a. group sorting does in fact occur
according to relative differences in power output, and that aggregates occur
because their effective fitness levels are narrowed by a "drafting" effect so
their speeds are identical;
b. there is a correlation between aggregate size
(ie. number of agents), differences in relative maximum sustainable output, and
the time to which group sorting occurs.
The prediction is that the time required
for group sorting to occur increases as aggregate size
increases and relative differences in max output capacities
("fitness") become smaller. In other words where agents are
identically fit, they will all stay in one group and will never sort
(generally); where fitness levels are different, they will sort
rapidly. Drafting facilitates the narrowing of fitness
levels, so even if there are intrinsic differences in output, agents
will aggregate if they can draft such that they travel at the same speed
and at effectively identical output levels.
At the moment, I have in mind that sperm aggregates
fall under the category of "weak" drafting, whereby they randomly/accidently
draft, but are incapable of seeking out drafting positions as are agents in
bicycle pelotons. Pelotons exhibit strong drafting. So, under a
weak drafting model, sperm sorting should occur at some rate faster than
pelotons. In a peloton, especially one in which the entire group consists
of riders of closely matched sustainable outputs (such as a group of
professional cyclists), the group will stay together to the finish (on a
uniform course). In a peloton, the primary cause of group
sorting is the occurrence of points in which drafting benefit is
reduced such that drafting no longer equalizes the entire range of output
levels, such as hills, course obstacles, and cross-winds (I have refered in the
past to these as instabilities in the system). The nature of the
proximity of sperm to one another may mean that their weak drafting results
in very long sort times, such that sort times are nearly the same as would
occur under a strong drafting situation, and that is something I can look for as
well. There may be some surprises along the way.
If I can complete the experiments, I may seek to
get the results published, or I may aim to present them first at the
2010 AAAI Conference and seek publication afterward. Basically the idea is
to establish a model by which predictions can be made for real aggregations, and
the model should be applicable essentially to all aggregates which move at
maximum sustainable outputs and where there is some energy saving component
involved in coupled motion. It won't apply where aggregates move at outputs
significantly below max sustainable outputs, because in those situations even
the weakest agent can keep up with the strongest (the extreme situation is where
they all stand still, or move at the equivalent of a slow walking pace). It can
apply, however, in situations where there is broad range of fitness
levels and only some agents move at maximum sustainable output,
because a small increase in output among the group causes those already at max
output to be sorted "off the back", even when many among the group are not at
max output.
Vladimyr - sorry I haven't responded yet on a
couple of your posts - I've realized I need to knuckle down and really work
through a simulation, and have become focussed on that at this point. I
hope to be involved in this discussion more, however, over time.
Hugh
----- Original Message -----
============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org |
| Free forum by Nabble | Edit this page |