Posts tonen met het label ©readings. Alle posts tonen
Posts tonen met het label ©readings. Alle posts tonen
zaterdag 26 november 2011
Stanford's Free Computer Science Courses
Stanford's Free Computer Science Courses: Stanford University is offering the online world more of its undergraduate level courses. These free courses consist of You Tube videos with computer-marked quizzes and programming assignments.
dinsdag 11 oktober 2011
De filosofische benadering van cognitiewetenschap
De filosofische benadering van cognitiewetenschap: Hoe wordt er vanuit de filosofie gekeken naar de cognitiewetenschap? Wat is monisme? En wat is dualisme? Deze termen en vele andere worden in dit arti…
vrijdag 15 juli 2011
De Reformatie: Religie is politiek
De Reformatie: Religie is politiek: "
Toen de Duitse priester Maarten Luther in 1510 Rome bezocht, vierde de decadentie en corruptie zijn hoogtijdagen in de Heilige Stad. Hij zag priesters die bordelen bezochten en aflaten die zelfs nog aan doodsbange nabestaanden van overledenen verkocht werden, om voor hen maar een plekje in de hemel veilig te stellen. Wie maar genoeg betaalde kon zelfs het ambt van priester kopen.
Luther verwoorde zijn kritiek in pamfletten die hij verspreide in zijn thuisstad Wittenberg. Ook vatte hij zijn ideeën over wat er allemaal mis was in de Katholieke kerk samen in 95 stellingen die hij, rebels als hij was, prominent op de deur van de kathedraal van de stad spijkerde.
In 1529 stelde Luther de “Reichstag”: van het Heilig Roomse Rijk voor het dogma van de eucharistie voortaan te verwerpen. Een definitieve breuk met de Katholieke kerk in Rome zou daarmee onvermijdelijk zijn. Omdat Luther in zijn theologie ook had opgenomen dat de Paus zich niet met politieke zaken zou moeten bezighouden, zagen veel regionale Duitse vorsten de nieuwe Christelijke leer wel zitten.
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Veertiende- en vijftiende-eeuwse intellectuelen als Jan Hus en John Wycliffe hadden al pogingen ondernomen de Katholieke kerk van binnenuit te hervormen. Met name voor Jan Hus liep zijn kritiek op de praktijken binnen de Kerk slecht af. In 1415 werd hij levend verbrand wegens ketterij. Aan het begin van de zestiende eeuw ontstond er een nieuwe generatie van hervormers die het er voortvarender vanaf brachten.
Duitsland staat nog altijd vol met standbeelden van kerkhervormer Luther, zoals hier in Dresden. Afbeelding: © Wikimedia Commons
Luther verwoorde zijn kritiek in pamfletten die hij verspreide in zijn thuisstad Wittenberg. Ook vatte hij zijn ideeën over wat er allemaal mis was in de Katholieke kerk samen in 95 stellingen die hij, rebels als hij was, prominent op de deur van de kathedraal van de stad spijkerde.
Luther’s kritiek richtte zich vooral op de corruptie van de geestelijkheid. Ook was hij van mening dat de Bijbel ook in andere talen dan het Latijn beschikbaar zou moeten zijn. Een idee dat nog altijd de kern van de Reformatie vormt maar niet zo nieuw was als vaak word gedacht.
Dankzij de kort daarvoor uitgevonden boekdrukkunst konden de ideeën van Luther zich snel verspreiden. Andere prominente Christelijke denkers, zoals de Zwitser Ulrich Zwingli en de Fransman Johannes Calvijn waren er evenals Luther van overtuigd dat er iets moest veranderen binnen het Christendom. Op dat moment hadden deze denkers geen plannen de Katholieke Kerk te verlaten en nieuwe kerkgemeenschappen te stichten. Wel ontstonden er er snel heftige discussies over welke kant het dan wél op moest met de inrichting van het geloof.
Bloed en lichaam
Bestaat de vrije wil? Veranderen de wijn en het brood tijdens de eucharistieviering echt in het bloed in lichaam van Christus? Tegenwoordig zijn dat vragen die buiten de kerk weinig mensen nog echt het overdenken waard vinden, maar gedurende de zestiende eeuw waren het religieuze twistpunten die een belangrijke weerslag op de politiek in Europa hadden.
Sterker nog, het Katholieke dogma dat het brood en de wijn werkelijk in het lichaam en bloed van Christus veranderde (mits door een priester toegediend), maakte zo’n belangrijk deel uit van de Katholieke theologie dat Luther’s verwerping daarvan het begin vormde van grootschalige politieke omwentelingen in vrijwel heel Europa.
Rond 1500 besloeg het Heilig Roomse Rijk een groot deel van Europa. Een hechte politieke eenheid was het echter nooit. De opkomst van de Reformatie droeg eraan bij dat het enorme Rijk in de zestiende en zeventiende eeuw verscheurd werd door interne oorlogen. Afbeelding: © Wikimedia Commons
Deze machthebbers wilden baas in eigen huis zijn en wilde af van de bemoeienissen vanuit de Rome op hun politiek. Met name in het noorden van het Rijk kreeg Luther veel steun. De religieuze twistpunten vertaalden zich vrijwel direct in politieke spanningen door het hele rijk.
Religie en politiek waren in de vroegmoderne tijd buitengewoon nauw met elkaar verweven. Binnen korte tijd raakte Europa verdeeld in aanhangers van protestantisme en katholicisme, van behoud en hervorming, van machthebbers die hun voordeel probeerden te doen met de nieuwe ontwikkelingen en zij die de status quo wilden behouden.
Als gevolg van deze spanningen scheurde de Dertigjarige Oorlog tussen 1618 en 1648 het Heilig Roomse Rijk uiteen. In vrijwel elk Europees land woedde ergens in de zestiende of zeventiende eeuw wel een godsdienstoorlog als direct of indirect gevolg van deze wisselwerking tussen religie en politiek. De Tachtigjarige oorlog in de Nederlanden is slechts een van de vele.
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donderdag 26 mei 2011
absolute macht
in het romeinse rijk was de absolute macht gelegd bij een mens: de keizers
vervolgens dreef de absolute macht naar een onzichtbare entiteit: god
om daarna de absolute macht te herverdelen over het hele volk: democratie
wellicht dat de volgende stap de absolute macht is van de wetenschap waarmee ze het individu beroven van hun vrij wil, en zelfs voor de geboorte van het individu al weten wat het stemmen zal.
vervolgens dreef de absolute macht naar een onzichtbare entiteit: god
om daarna de absolute macht te herverdelen over het hele volk: democratie
wellicht dat de volgende stap de absolute macht is van de wetenschap waarmee ze het individu beroven van hun vrij wil, en zelfs voor de geboorte van het individu al weten wat het stemmen zal.
Persbricht | TNT Post wordt PostNL | TNT Post
Persbricht | TNT Post wordt PostNL | TNT Post: "Na goedkeuring door de vergadering van aandeelhouders op 25 mei 2011 gaat TNT Post op 31 mei 2011 als zelfstandig postbedrijf verder onder de nieuwe naam PostNL. Het bedrijf is er trots op het predikaat ‘Koninklijk’ te mogen blijven voeren."
Het effect op de nederlandse samenleving, nu ze dat explosieve woordje uit het straatbeeld opdoeken, zal misschien zijn dat de feestelijke violente incideneten rond begin mei (damschreeuwer, enschede-explosie, moord fortuyn, ridderhof-slachtpartij, aanslag koningin etc.) niet meer een jaarlijkse terugkerende gebeurtenis word.
Het effect op de nederlandse samenleving, nu ze dat explosieve woordje uit het straatbeeld opdoeken, zal misschien zijn dat de feestelijke violente incideneten rond begin mei (damschreeuwer, enschede-explosie, moord fortuyn, ridderhof-slachtpartij, aanslag koningin etc.) niet meer een jaarlijkse terugkerende gebeurtenis word.
donderdag 7 april 2011
Stuxnet, HAARP en de X37-B in de vernietiging van JAPAN!
Stuxnet, HAARP en de X37-B in de vernietiging van JAPAN!: "
Dat, terwijl Japan toch in 1945 de geboorte zag van het Nucleaire tijdperk. Hier werden voor het eerst in de geschiedenis high-tech wapens ingezet tegen de burgerbevolking van een land waarmee de Verenigde Staten in oorlog was. Nu zult u misschien denken, dat de VS op dit moment helemaal niet in oorlog zijn met Japan? Toch is dat precies wat Leuren Moret, nucleair wetenschapper beweert in een interview op Exopolitics TV: er wordt op dit moment een non-traditionele nucleaire oorlog gevoerd.
**Door gastzapper xaderp via het zaplog**
vrijdag 18 maart 2011
No-fly will fly
No-fly will fly: "
maandag 7 maart 2011
Why information can't be the basis of reality
Why information can't be the basis of reality: "
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Is everything information? This seductive idea animates the brand-new book The Information by James Gleick (Pantheon 2011), which I just rave-reviewed in The Wall Street Journal . Gleick's book is, among other things, an in-depth biography of information theory, which the Bell Labs mathematician Claude Shannon invented in 1948 to provide a framework for improving the efficiency of communications.
A growing number of scientists, Gleick writes, are beginning to wonder whether information "may be primary: more fundamental than matter itself." This notion has inspired other recent books, including Programming the Universe by Seth Lloyd (Vintage 2007), Decoding the Universe by Charles Seife (Penguin 2007), Decoding Reality by Vlatko Vedral (Oxford 2010) and Information and the Nature of Reality , a collection of essays edited by Paul Davies (Cambridge 2010). But the everything-is-information meme violates common sense.
[More]"
dinsdag 1 maart 2011
ouderen en oorlog
Vreemd toch hoe die ouderen die de oorlog hebben meegemaakt, hun identiteit zozeer laten afhangen van hun interieur en spulletjes, waarschijnlijk omdat ze tijdens de oorlog vaak veilig binnen bleven.
En hoe ze zich beschermd voelen door hun wreedste generatiegenoten.
En hoezeer ze de buren een vijand vinden waarmee ze zich kunnen meten, net zoals nederland mat met de duitse buren had.
En dan de affiniteit met sigaretten, net zoals ze die zagen bij GI Joe.
En men hoeft zich ook niks aan te trekken van anderen want dat zijn toch maar potentiele verraders of anderszins egoisten. En het belangrijkste: van verzet wil men niets weten.
De bescherming door de rechtsstaat hebben ze niet tijdens de opvoeding ervaren, vaderlandsliefde des te meer. De huidige generaties kennen het gebrek aan rechtsstaat niet, en dus wordt het weer oorlog. Want wie wil zijn naasten nu niet begrijpen?.
En hoe ze zich beschermd voelen door hun wreedste generatiegenoten.
En hoezeer ze de buren een vijand vinden waarmee ze zich kunnen meten, net zoals nederland mat met de duitse buren had.
En dan de affiniteit met sigaretten, net zoals ze die zagen bij GI Joe.
En men hoeft zich ook niks aan te trekken van anderen want dat zijn toch maar potentiele verraders of anderszins egoisten. En het belangrijkste: van verzet wil men niets weten.
De bescherming door de rechtsstaat hebben ze niet tijdens de opvoeding ervaren, vaderlandsliefde des te meer. De huidige generaties kennen het gebrek aan rechtsstaat niet, en dus wordt het weer oorlog. Want wie wil zijn naasten nu niet begrijpen?.
zondag 20 februari 2011
Carrièreswitch: kunt u een dictator worden?
Carrièreswitch: kunt u een dictator worden?: "Hitler, Saddam Hoessein, Josef Stalin: de afgelopen eeuwen leefden er veel dictators op aarde. En zelfs anno 2011 schieten er nieuwe tirannen uit de grond. Een dictator is vaak narcistisch en paranoïde, zo beweren psychologen. De vraag is of deze mensen zo zijn geworden of dat ze dat al hun hele leven waren. Kan een [...]
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vrijdag 14 januari 2011
The rules of attraction: the not so golden mean | Gene Expression
The rules of attraction: the not so golden mean | Gene Expression: "
Several people have inquired as to my opinion on the OKCupid post The Mathematics Of Beauty. I’ve blogged data from this dating website in the past, in particular, the differential race consciousness of women vs. men. But that material is a different class than the current post. As I have noted before, there is a robust result in the social science research over the past decade which suggests that women express & reveal more race consciousness than men when it comes dating & mating. The previous OKCupid analysis wasn’t ground-breaking, it simply added some wrinkles into a series of patterns which were replicated in the literature. The current results are different insofar as I haven’t followed the academic literature which relates to this in detail. This matters because unlike most of my peers I’ve done very little online dating (basically 2 weeks in the summer of 2002), and so can’t bring a personal familiarity with the topic to the discussion. To be sure, plenty of my friends have discussed their issues with online dating with me, so I’m not ignorant of the phenomenon. My male friends routinely complain how difficult it is to get the attention of women who are bombarded by messages from all directions. A female friend who is in her mid-30s chronologically, but physically resembles a women in her 20s, has complained how men clearly have automatic age filters set for searches which are working against her.
Let’s start at the beginning. To the left you see a scatter plot of # of messages received by women per month as a function of their rated attractiveness. They controlled for background variables (e.g., race). On the one hand, the results aren’t surprising. You see that more attractive women receive more messages. But on the other hand, the residual (noise) around the trend line is enormous, especially in the top half the distribution. I am personally rather surprised at the enormous variance of message # at the higher ratings. But here’s an important point: this is the mean rating of attractiveness. It turns out there’s a substantial variance around the means of attractiveness for any given mean value. There are two ways to look at this. It seems there is a general consensus about a mean of a distribution as to someone’s attractiveness level. In other words, you don’t have a preponderance of uniform distributions, suggesting that attractiveness is extremely plastic. This is in line with what evolutionary psychologists have found: people from “small scale” societies can ascertain who is, or isn’t, attractive in a set of photos of Europeans. But there’s another part of the story: differences in opinions about physical attractiveness of the same person from the vantage point of outsiders.
To the right you have the top line results. The plot shows the response # as a function of variance of assessments for women at the 80th percentile of attractiveness. As you can see it looks like the number of messages starts to rise as a linear function above the center of the variance range. Below the curve you see an equation which predicts the number of messages as a function of the shape of the distribution. Apparently OKCupid attractiveness measures range from 1 to 5, and the coefficients in front of the values indicate the effect upon the final number of messages. So, if all the men rated a woman a 5, then you’d expect an increase of messages above expectation. The weird thing from the equation is this: according to the model it is better to have everyone evaluate you a 1 than everyone evaluate you a 4. Look at the signs of the coefficient. I don’t personally believe this outcome is valid. In fact, I assume that there’s no one in their data who was rated a 1 by everyone, or, a 4 by everyone. These sorts of models are giving us precise inferences, but the models themselves are only rough correspondences to broader underlying dynamics (which is why people argue over which model better “fits” data and such). Pushing a model to ludicrous extremes doesn’t necessarily give us insight. Rather, it suggests that we should be careful about confusing the model for reality (just as we should be careful about confusing a mean for the totality of the shape of the distribution). I suspect the equation would be different if one constrained the range of attractivenes (e.g., 50th to 100th percentile vs. 25th to 75th percentile), but the qualitative result would hold. The model may be precise, but the inferences we make should be a little less precise.
The authors of the OKCupid post implicitly give a nod to this, illustrating the peculiar pattern of variation in message responses. Their data set indicates that a woman who received more extreme reactions would receive more messages than a woman who received more uniform reactions, even if the latter had a higher average rating than the former. This is certainly counterintuitive. What’s going on here?
First, let’s present the OKCupid explanation:
In some ways this was the model that my college roommate was espousing. His argument was that the key was to find a woman who you found more attractive than the average bear. That way, you were in a better bargaining position to select good mates from this pool of women, who don’t necessarily know their own leverage over you, because they have to assume that you’re the typical male. The “win-win” scenario is where two people perceive each other to be better “catches” than the general population when it comes to looks. There are a lot of such cases presumably because of the residual you see above, but there are plenty of other factors in mates where one can be choosy. By maximizing the disjunction between between population-wide assessment of attractiveness and your own perception of a woman’s attractiveness you can “negotiate” for someone “better” on the other characteristics you value than you otherwise might be able to. If you want to be happy the key isn’t to find a woman you find ugly, it is to find a woman who you value more than the going “market” rate.
Alex Tabarrok has another plausible explanation:
Alex’s model is not totally exclusive of the one OKCupid was espousing. Both of them clearly suggest that distinctiveness matters. Individuals have their own “brands,” and accentuating brands can allow for your “market segment” to target you. Back during my 2 weeks of internet dating I put “atheist” under religion, and indicated that I did not want inquiries from someone who was religious. I was well aware that this was putting me into a “sausage surplus” market, as there seems to be a preponderance of males among those who espouse such frank irreligiosity. But I recall hoping that my honesty about this would at least attract the attention of women who shared a similar disinclination toward religion (this turned out be a good move, a woman who was raised Jehovah’s Witness but had left religion contacted me). That being said, I did have my limits. I did not play up the fact that I was a Republican, as I judged that the pool of atheist Republican women in Portland, Oregon (where I lived at the time), was very small. It must also be admitted that my personal experience is that similar politics is less important in the success of a relationship than a common “metaphysic.” In my case this is partly probably a function of a general weak passion for politics at this stage of my life. But even when I was a very strident libertarian politics was never a litmus test for relationships and friendships.
At this point I’d like to introduce a stylized model. In Survival of the Prettiest Nancy Etcoff introduced me to two different types of beauty. The first you should be well aware of: more symmetry means that you are more attractive. Composites of a range of individuals are almost always more attractive than the individuals themselves. This is attributed to the asymmetry which is introduced in development due stochastic, environmental, and genetic factors. Being lopsided is not a good sign of health, whether the cause is endogenous or exogenous. But there is another sort of beauty: that focused on secondary sexual characteristics, which are sex specific. Symmetrical beauty is applicable in the same manner to both sexes. This secondary sexual characteristic component is not. A powerful robust chin which may indicate rugged good looks in a man does not do so on a woman. Large eyes, a small nose, and a pert mouth, may be attractive on a woman, but they may seem ludicrous on a man (unless you’re Speed Racer). In the case of symmetry being at the mean is the best. But in the case of secondary sexual characteristics exhibiting some deviation from the mean of your sex in one particular direction is probably ideal. Let’s call this “good” deviation.
Finally, there’s a third component. To some extent this is like “non-shared environment” in many behavior genetic models. It’s a whole host of factors thrown together to explain the residual which can not be accounted for by the two other variables. So that’s why I labelled it “X” factor. Probably the easiest sub-component to pick out here are cultural influences as a function of space and time. To the right you see two photos. One is of the Bollywood actress Karisma Kapoor, while the other is of the Indian actress Freida Pinto. To be honest the photo of Ms. Kapoor is probably more flattering when it comes to the range of her photos than that of Ms. Pinto. A large fraction of the reason that Ms. Kapoor is a Bollywood star is contingent. She’s from a showbiz family, and nepotism seems to count for a lot in the film entertainment industry in India and the USA. But another factor is that Ms. Kapoor is extremely “fair” by Indian standards. In contrast, Ms. Pinto is more conventionally Indian looking. My personal experience is that Westerners, and brown folk raised in the West, have a hard time understanding how someone who is as “conventional” looking as Ms. Kapoor could be a leading lady. But she is very unconventional in complexion in South Asia, and in a good way. In contrast, Ms. Pinto is more conventionally good looking. She is of normal coloring for a South Asian. I am willing to bet that most Westerners would judge Ms. Pinto more attractive than Ms. Kapoor without makeup. Anyone who has encountered 19th century Chinese foot binding literary porn will be rather aware of how cultural expectations and norms can reshape and distort beauty standards. In a Western context the shift toward slimness away from a more ample form is often used to illustrate the principle of variance of tastes and standards over time. But these realities should not allow us to forget that common factors do tend to remain invariant. It is famously observed that though the size of the ideal woman in the West has shifted a great deal, the ideal ratio of proportions have moved far less.
But there may be genuine differences which are not so temporally or cultural sensitive. Another component of the third dimension of assessment of attractiveness is probably just individual differences. The domain of behavior genetics, as opposed to evolutionary psychology. There are after all “legs” and “breasts” and “butt” men. Granted, the proportions vary across cultures, but there nevertheless remains a mix in most cultures of preferences. I believe this aspect is the one that may explain much of the pattern in the OKCupid results. There are men who prefer very small breasts, men who prefer corpulent women, and so forth. Whatever the origin of these preferences, even assuming relative cultural invariance in the sample population (I believe this is so for the middle to upper middle class Western target audience of OKCupid) there will remain individual differences of taste and preference, as noted by Alex Tabarrok. Women sharply deviated from the population norm on many traits may produce an average decline in aggregate attractiveness rating, but still may command a premium among the target audience of men who prefer the deviated traits (e.g., attractiveness drops as the number and extremity of piercings increases for the general population, but increases for a minority who find that attractive). Quite often it is preferable to be a second choice, but in this case women who are blandly “cute” may suffer because of the way in which men allocate their time and energy. Dating sites such as OKCupid have many more potential target matches than not, so why not focus on those individuals with whom one is the best match with, instead of the second best? In this way OKCupid is perhaps very different from the small villages or tribes of yore; you have thousands of “first matches.”
Finally, I want to observe something about the images on the OKCupid post. Quite often it seemed that the women who had higher variance ratings used more salient photos, with harsher or higher key lighting. A woman who uses a classic “MySpace angle” photo that’s a touch on the blurry side may get higher ratings than a woman who uses a more crisp image without makeup, but I suspect that many men would prefer the latter to the former. One can’t rate someone lower just for being clever with lighting and selection biasing, but, one may change one’s behavior explicitly and implicitly taking that into account.
In any case, I’ve gone on long enough. I was asked my opinion, and I gave it. What’s your take? (this is not a call for retarded comments by the way. You know who you are)
Image credit: Xavier449, Bollywood Hungama, Lili Ferraz.
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Wat betreft de voorlaatste alinea over de fotokwaliteit, ook dat is geanalyseerd, zie alhier bij OKCupid, en voor de ¨non-shared environment¨ kan men ook op OKCupid terecht.
Het gaat er volgens mij om dat de aantal ontvangen berichten toeneemt als er een groter meningsverschil over de attractiviteit van de persoon in kwestie bestaat zoals OKCupid beweert en wat betreft de deviatiegraad en de variantiefunctie van OKCupid indien ze wel geldig is: mannen houden niet van ondernemende vrouwen maar wel van impulsieve chicks, weet je dan het resultaat? Dat mannen er ook niet van houden dat ze in een ander cafe zit dan in die ene waar hijzelf zit.
En .4*5 - .5*4 - .1*9 + .9*1 + k= nul berichten maar ook 19 kiezers waarvan 9 haar ondergemiddeld waarderen en 10 haar bovengemiddeld waarderen. En waarom stuurt ook die ene die haar perfect vindt geen bericht? Omdat die 9 die haar met een 4 waarderen ook niks doen, dat is niet counterintuitief, maar normaal als ze aan iedere vinger 10 man heeft waarbij die 9 afwachten wat die ene doet. En bij een ondergemiddelde waardering lijken de kiezers elkaar meer te steunen. Maw. in deze variantie of stemgedrag ontvangt men dus geen berichten.
Er zijn echter 49 manieren waarop 60 kiezers die eenmaal verplicht stemmen en toch nul berichten zullen versturen. Er zijn zelfs 1032 manieren om nul berichten te versturen als niet alle 60 kiezers hun stemmen verdelen en sommige zich dus van stemming onthielden, waardoor het gemiddelde dan zweeft bij 74,52% kiezers die dan wel eenmaal gestemd hebben.
En bij 5 verstuurde berichten ligt bij vrijwillige deelname aan stemming bij 60 kiezers het aantal manieren van waardering op 1418 en zweeft het gemiddeld aantal kiezers op 73,44%
Voor verschillende populatie grootte kan men de volgende grafiek beschouwen (en k van de formule buiten beschouwing is gelaten) waarbij op de x-as het aantal msgs en op de y-as het aantal varianties in de manier waarop men gewaardeerd kan worden bij dat specifiek aantal msgs (afb1a):
het hoogst aantal verschillende waarderingen (ways) waarbij 15 mensen stemden lag bij 39 manieren (varianties) voor 2 msgs, bij 30 mensen is het maximum 239 manieren wat leidt tot 4 msgs, bij 45 mensen was het maximum 768 manieren voor 8 msgs, bij 60 mensen werd het maximum 1705 manieren ook voor 8 msgs, bij 75 mensen was de kans het grootst door 3119 manieren voor 16 msgs en bij 90 mensen was het maximale bij 5507 manieren ook voor 16 msgs. (afb 1a)
Het zig-zag patroon in de grafiek (afb 1a en 1b) waarbij dus 1 msgs meer word verstuurd bij een langzame vermindering of sprongsgewijze vermeerdering van manieren van waardering kan komen doordat men niet de kans wil laten ontglippen? Dan lijkt het erop dat 4 pogingen ongeveer de maximale moeite zijn, alhoewel het ook afhankelijk van de grootte van de populatie lijkt. (afb 1b)
Voor iedere populatie geldt dat de deelname aan stemming steeds begint onder de 75% (afb 2 en 3) en als 100% van de populatie wordt bereikt (afb 3) dan zijn er ook maximaal nog slechts 4 varianties van waardering. In het begin wil de lijn nog krullen (afb 2) en loopt deelname zelfs nog terug bij de eerste 10 berichten. Maar waarom het aantal varianties soms spronggewijs toeneemt bij een toenemende participatie of betrokkenheid is me niet duidelijk, kritische massa misschien?.
Het verschil tussen de verstuurde berichten bij het bereiken van 100% deelname van de verschillende populaties (afb 3) is steeds 13 of 14 msgs. maw. bij 15 mensen meer kan men ongeveer 13 msgs meer verwachten bij 100% deelname.
Om 125 msgs te ontvangen moet dus extrapolerend de populatiegrootte minimaal ongeveer 150 mensen zijn.
Op de lijn (afb 4) staan de populatiegroottes waarbij het aantal msgs (x-as) bij het maximale aan varianties (y-as) steeds verdubbelde.
Hoe groter de populatie hoe groter de kans op meer msgs. (afb 5)
Several people have inquired as to my opinion on the OKCupid post The Mathematics Of Beauty. I’ve blogged data from this dating website in the past, in particular, the differential race consciousness of women vs. men. But that material is a different class than the current post. As I have noted before, there is a robust result in the social science research over the past decade which suggests that women express & reveal more race consciousness than men when it comes dating & mating. The previous OKCupid analysis wasn’t ground-breaking, it simply added some wrinkles into a series of patterns which were replicated in the literature. The current results are different insofar as I haven’t followed the academic literature which relates to this in detail. This matters because unlike most of my peers I’ve done very little online dating (basically 2 weeks in the summer of 2002), and so can’t bring a personal familiarity with the topic to the discussion. To be sure, plenty of my friends have discussed their issues with online dating with me, so I’m not ignorant of the phenomenon. My male friends routinely complain how difficult it is to get the attention of women who are bombarded by messages from all directions. A female friend who is in her mid-30s chronologically, but physically resembles a women in her 20s, has complained how men clearly have automatic age filters set for searches which are working against her.
Let’s start at the beginning. To the left you see a scatter plot of # of messages received by women per month as a function of their rated attractiveness. They controlled for background variables (e.g., race). On the one hand, the results aren’t surprising. You see that more attractive women receive more messages. But on the other hand, the residual (noise) around the trend line is enormous, especially in the top half the distribution. I am personally rather surprised at the enormous variance of message # at the higher ratings. But here’s an important point: this is the mean rating of attractiveness. It turns out there’s a substantial variance around the means of attractiveness for any given mean value. There are two ways to look at this. It seems there is a general consensus about a mean of a distribution as to someone’s attractiveness level. In other words, you don’t have a preponderance of uniform distributions, suggesting that attractiveness is extremely plastic. This is in line with what evolutionary psychologists have found: people from “small scale” societies can ascertain who is, or isn’t, attractive in a set of photos of Europeans. But there’s another part of the story: differences in opinions about physical attractiveness of the same person from the vantage point of outsiders.
To the right you have the top line results. The plot shows the response # as a function of variance of assessments for women at the 80th percentile of attractiveness. As you can see it looks like the number of messages starts to rise as a linear function above the center of the variance range. Below the curve you see an equation which predicts the number of messages as a function of the shape of the distribution. Apparently OKCupid attractiveness measures range from 1 to 5, and the coefficients in front of the values indicate the effect upon the final number of messages. So, if all the men rated a woman a 5, then you’d expect an increase of messages above expectation. The weird thing from the equation is this: according to the model it is better to have everyone evaluate you a 1 than everyone evaluate you a 4. Look at the signs of the coefficient. I don’t personally believe this outcome is valid. In fact, I assume that there’s no one in their data who was rated a 1 by everyone, or, a 4 by everyone. These sorts of models are giving us precise inferences, but the models themselves are only rough correspondences to broader underlying dynamics (which is why people argue over which model better “fits” data and such). Pushing a model to ludicrous extremes doesn’t necessarily give us insight. Rather, it suggests that we should be careful about confusing the model for reality (just as we should be careful about confusing a mean for the totality of the shape of the distribution). I suspect the equation would be different if one constrained the range of attractivenes (e.g., 50th to 100th percentile vs. 25th to 75th percentile), but the qualitative result would hold. The model may be precise, but the inferences we make should be a little less precise.
The authors of the OKCupid post implicitly give a nod to this, illustrating the peculiar pattern of variation in message responses. Their data set indicates that a woman who received more extreme reactions would receive more messages than a woman who received more uniform reactions, even if the latter had a higher average rating than the former. This is certainly counterintuitive. What’s going on here?First, let’s present the OKCupid explanation:
Suppose you’re a man who’s really into someone. If you suspect other men are uninterested, it means less competition. You therefore have an added incentive to send a message. You might start thinking: maybe she’s lonely. . . maybe she’s just waiting to find a guy who appreciates her. . . at least I won’t get lost in the crowd. . . maybe these small thoughts, plus the fact that you really think she’s hot, prod you to action. You send her the perfectly crafted opening message.
“sup”
On the other hand, a woman with a preponderance of ’4′ votes, someone conventionally cute, but not totally hot, might appear to be more in-demand than she actually is. To the typical man considering her, she’s obviously attractive enough to create the impression that other guys are into her, too. But maybe she’s hot enough for him to throw caution (and grammar) to the wind and send her a message. It’s the curse of being cute.
In some ways this was the model that my college roommate was espousing. His argument was that the key was to find a woman who you found more attractive than the average bear. That way, you were in a better bargaining position to select good mates from this pool of women, who don’t necessarily know their own leverage over you, because they have to assume that you’re the typical male. The “win-win” scenario is where two people perceive each other to be better “catches” than the general population when it comes to looks. There are a lot of such cases presumably because of the residual you see above, but there are plenty of other factors in mates where one can be choosy. By maximizing the disjunction between between population-wide assessment of attractiveness and your own perception of a woman’s attractiveness you can “negotiate” for someone “better” on the other characteristics you value than you otherwise might be able to. If you want to be happy the key isn’t to find a woman you find ugly, it is to find a woman who you value more than the going “market” rate.
Alex Tabarrok has another plausible explanation:
….Rather I think there are certain types of beauty that greatly attract some men but repel others. Analagously, some people will pay hundreds of dollars for an ounce of caviar that other people won’t eat for free. The reason some people love caviar, however, is not that other people dislike it. Instead, it just so happens, that the thing that some people love is the very thing that repels others. We see the same phenomena in art, some people love John Cage, other people would rather listen to nothing at all….
Alex’s model is not totally exclusive of the one OKCupid was espousing. Both of them clearly suggest that distinctiveness matters. Individuals have their own “brands,” and accentuating brands can allow for your “market segment” to target you. Back during my 2 weeks of internet dating I put “atheist” under religion, and indicated that I did not want inquiries from someone who was religious. I was well aware that this was putting me into a “sausage surplus” market, as there seems to be a preponderance of males among those who espouse such frank irreligiosity. But I recall hoping that my honesty about this would at least attract the attention of women who shared a similar disinclination toward religion (this turned out be a good move, a woman who was raised Jehovah’s Witness but had left religion contacted me). That being said, I did have my limits. I did not play up the fact that I was a Republican, as I judged that the pool of atheist Republican women in Portland, Oregon (where I lived at the time), was very small. It must also be admitted that my personal experience is that similar politics is less important in the success of a relationship than a common “metaphysic.” In my case this is partly probably a function of a general weak passion for politics at this stage of my life. But even when I was a very strident libertarian politics was never a litmus test for relationships and friendships.
At this point I’d like to introduce a stylized model. In Survival of the Prettiest Nancy Etcoff introduced me to two different types of beauty. The first you should be well aware of: more symmetry means that you are more attractive. Composites of a range of individuals are almost always more attractive than the individuals themselves. This is attributed to the asymmetry which is introduced in development due stochastic, environmental, and genetic factors. Being lopsided is not a good sign of health, whether the cause is endogenous or exogenous. But there is another sort of beauty: that focused on secondary sexual characteristics, which are sex specific. Symmetrical beauty is applicable in the same manner to both sexes. This secondary sexual characteristic component is not. A powerful robust chin which may indicate rugged good looks in a man does not do so on a woman. Large eyes, a small nose, and a pert mouth, may be attractive on a woman, but they may seem ludicrous on a man (unless you’re Speed Racer). In the case of symmetry being at the mean is the best. But in the case of secondary sexual characteristics exhibiting some deviation from the mean of your sex in one particular direction is probably ideal. Let’s call this “good” deviation.
Finally, there’s a third component. To some extent this is like “non-shared environment” in many behavior genetic models. It’s a whole host of factors thrown together to explain the residual which can not be accounted for by the two other variables. So that’s why I labelled it “X” factor. Probably the easiest sub-component to pick out here are cultural influences as a function of space and time. To the right you see two photos. One is of the Bollywood actress Karisma Kapoor, while the other is of the Indian actress Freida Pinto. To be honest the photo of Ms. Kapoor is probably more flattering when it comes to the range of her photos than that of Ms. Pinto. A large fraction of the reason that Ms. Kapoor is a Bollywood star is contingent. She’s from a showbiz family, and nepotism seems to count for a lot in the film entertainment industry in India and the USA. But another factor is that Ms. Kapoor is extremely “fair” by Indian standards. In contrast, Ms. Pinto is more conventionally Indian looking. My personal experience is that Westerners, and brown folk raised in the West, have a hard time understanding how someone who is as “conventional” looking as Ms. Kapoor could be a leading lady. But she is very unconventional in complexion in South Asia, and in a good way. In contrast, Ms. Pinto is more conventionally good looking. She is of normal coloring for a South Asian. I am willing to bet that most Westerners would judge Ms. Pinto more attractive than Ms. Kapoor without makeup. Anyone who has encountered 19th century Chinese foot binding literary porn will be rather aware of how cultural expectations and norms can reshape and distort beauty standards. In a Western context the shift toward slimness away from a more ample form is often used to illustrate the principle of variance of tastes and standards over time. But these realities should not allow us to forget that common factors do tend to remain invariant. It is famously observed that though the size of the ideal woman in the West has shifted a great deal, the ideal ratio of proportions have moved far less.
But there may be genuine differences which are not so temporally or cultural sensitive. Another component of the third dimension of assessment of attractiveness is probably just individual differences. The domain of behavior genetics, as opposed to evolutionary psychology. There are after all “legs” and “breasts” and “butt” men. Granted, the proportions vary across cultures, but there nevertheless remains a mix in most cultures of preferences. I believe this aspect is the one that may explain much of the pattern in the OKCupid results. There are men who prefer very small breasts, men who prefer corpulent women, and so forth. Whatever the origin of these preferences, even assuming relative cultural invariance in the sample population (I believe this is so for the middle to upper middle class Western target audience of OKCupid) there will remain individual differences of taste and preference, as noted by Alex Tabarrok. Women sharply deviated from the population norm on many traits may produce an average decline in aggregate attractiveness rating, but still may command a premium among the target audience of men who prefer the deviated traits (e.g., attractiveness drops as the number and extremity of piercings increases for the general population, but increases for a minority who find that attractive). Quite often it is preferable to be a second choice, but in this case women who are blandly “cute” may suffer because of the way in which men allocate their time and energy. Dating sites such as OKCupid have many more potential target matches than not, so why not focus on those individuals with whom one is the best match with, instead of the second best? In this way OKCupid is perhaps very different from the small villages or tribes of yore; you have thousands of “first matches.”
Finally, I want to observe something about the images on the OKCupid post. Quite often it seemed that the women who had higher variance ratings used more salient photos, with harsher or higher key lighting. A woman who uses a classic “MySpace angle” photo that’s a touch on the blurry side may get higher ratings than a woman who uses a more crisp image without makeup, but I suspect that many men would prefer the latter to the former. One can’t rate someone lower just for being clever with lighting and selection biasing, but, one may change one’s behavior explicitly and implicitly taking that into account.
In any case, I’ve gone on long enough. I was asked my opinion, and I gave it. What’s your take? (this is not a call for retarded comments by the way. You know who you are)
Image credit: Xavier449, Bollywood Hungama, Lili Ferraz.
"Wat betreft de voorlaatste alinea over de fotokwaliteit, ook dat is geanalyseerd, zie alhier bij OKCupid, en voor de ¨non-shared environment¨ kan men ook op OKCupid terecht.
Het gaat er volgens mij om dat de aantal ontvangen berichten toeneemt als er een groter meningsverschil over de attractiviteit van de persoon in kwestie bestaat zoals OKCupid beweert en wat betreft de deviatiegraad en de variantiefunctie van OKCupid indien ze wel geldig is: mannen houden niet van ondernemende vrouwen maar wel van impulsieve chicks, weet je dan het resultaat? Dat mannen er ook niet van houden dat ze in een ander cafe zit dan in die ene waar hijzelf zit.
En .4*5 - .5*4 - .1*9 + .9*1 + k= nul berichten maar ook 19 kiezers waarvan 9 haar ondergemiddeld waarderen en 10 haar bovengemiddeld waarderen. En waarom stuurt ook die ene die haar perfect vindt geen bericht? Omdat die 9 die haar met een 4 waarderen ook niks doen, dat is niet counterintuitief, maar normaal als ze aan iedere vinger 10 man heeft waarbij die 9 afwachten wat die ene doet. En bij een ondergemiddelde waardering lijken de kiezers elkaar meer te steunen. Maw. in deze variantie of stemgedrag ontvangt men dus geen berichten.
Er zijn echter 49 manieren waarop 60 kiezers die eenmaal verplicht stemmen en toch nul berichten zullen versturen. Er zijn zelfs 1032 manieren om nul berichten te versturen als niet alle 60 kiezers hun stemmen verdelen en sommige zich dus van stemming onthielden, waardoor het gemiddelde dan zweeft bij 74,52% kiezers die dan wel eenmaal gestemd hebben.
En bij 5 verstuurde berichten ligt bij vrijwillige deelname aan stemming bij 60 kiezers het aantal manieren van waardering op 1418 en zweeft het gemiddeld aantal kiezers op 73,44%
Voor verschillende populatie grootte kan men de volgende grafiek beschouwen (en k van de formule buiten beschouwing is gelaten) waarbij op de x-as het aantal msgs en op de y-as het aantal varianties in de manier waarop men gewaardeerd kan worden bij dat specifiek aantal msgs (afb1a):
 | |
| afb 1a |
Het zig-zag patroon in de grafiek (afb 1a en 1b) waarbij dus 1 msgs meer word verstuurd bij een langzame vermindering of sprongsgewijze vermeerdering van manieren van waardering kan komen doordat men niet de kans wil laten ontglippen? Dan lijkt het erop dat 4 pogingen ongeveer de maximale moeite zijn, alhoewel het ook afhankelijk van de grootte van de populatie lijkt. (afb 1b)
 | |
| afb 1b |
 |
| afb 2 |
Voor iedere populatie geldt dat de deelname aan stemming steeds begint onder de 75% (afb 2 en 3) en als 100% van de populatie wordt bereikt (afb 3) dan zijn er ook maximaal nog slechts 4 varianties van waardering. In het begin wil de lijn nog krullen (afb 2) en loopt deelname zelfs nog terug bij de eerste 10 berichten. Maar waarom het aantal varianties soms spronggewijs toeneemt bij een toenemende participatie of betrokkenheid is me niet duidelijk, kritische massa misschien?.
 |
| afb 3 |
Het verschil tussen de verstuurde berichten bij het bereiken van 100% deelname van de verschillende populaties (afb 3) is steeds 13 of 14 msgs. maw. bij 15 mensen meer kan men ongeveer 13 msgs meer verwachten bij 100% deelname.
Om 125 msgs te ontvangen moet dus extrapolerend de populatiegrootte minimaal ongeveer 150 mensen zijn.
 |
| afb 4 |
Op de lijn (afb 4) staan de populatiegroottes waarbij het aantal msgs (x-as) bij het maximale aan varianties (y-as) steeds verdubbelde.
Hoe groter de populatie hoe groter de kans op meer msgs. (afb 5)
 | |
| afb 5 |
donderdag 13 januari 2011
Het gaat niet goed met de democratie in de wereld - Nieuws - VK
Het gaat niet goed met de democratie in de wereld - Nieuws - VK
De nederlandse identiteit verkeert ook in een crisis en hoort ook niet bij de 115 democratieen, het is eerder een politiestaat geworden.
Door schaalvergroting (denk europa) heeft de nederlandse grote bek (wilders) zichzelf voorgoed belachelijk gemaakt in het buitenland.
De nederlandse kiezer dacht dat door politiek zo grofgebekt te zijn als hij is als werknemer ivg. met andere landen, hij als handelaar kan overleven.
En offert gemakshalve zijn democratie op aan de economie.
De nederlandse identiteit verkeert ook in een crisis en hoort ook niet bij de 115 democratieen, het is eerder een politiestaat geworden.
Door schaalvergroting (denk europa) heeft de nederlandse grote bek (wilders) zichzelf voorgoed belachelijk gemaakt in het buitenland.
De nederlandse kiezer dacht dat door politiek zo grofgebekt te zijn als hij is als werknemer ivg. met andere landen, hij als handelaar kan overleven.
En offert gemakshalve zijn democratie op aan de economie.
woensdag 12 januari 2011
consider deze meme:
Een voorbeeld: het valse rood is links oranje en het valse geel is rechts groen, het ware rood hoort rechts en het ware geel is links gezien.
Indien men nu de qualia waar en vals van de velden verwisselt hoort men een heel andere getuigenis. Zo ziet een psychogram van een meme vermenigvuldiging uit en kan men de volgende stap zetten mbt. de mogelijkheden.
dinsdag 28 december 2010
Halverwege 2011 zijn we officieel met zeven miljard
Halverwege 2011 zijn we officieel met zeven miljard: "In de nacht van het oude op het nieuwe jaar zullen er volgens de Duitse stichting DSW (Deutschen Stiftung Weltbevölkerung) waarschijnlijk 6.934.196 000 mensen op de Aarde leven. Dat zijn er ongeveer 80 miljoen meer dan bij de vorige ..."
zondag 5 december 2010
Quest to Find a Menagerie of Exotic Particles
Quest to Find a Menagerie of Exotic Particles: "The hypothetical 'X' particle recently suggested as a dark matter candidate by scientists at Brookhaven isn't the only exotic particle that physicists have proposed in recent years.
"
zondag 21 november 2010
Vintage Diary
Vintage Diary: "
"
juist, dat werd dus madeleine sergant-logisch redeneren uitgever acco, met als resultaat: de latius hos regel.
De ironie.
"juist, dat werd dus madeleine sergant-logisch redeneren uitgever acco, met als resultaat: de latius hos regel.
De ironie.
zaterdag 20 november 2010
42 = 101010 = XXX
wat je voor je veertigste moeiteloos en zonder energie voor mekaar kreeg, daar moet je na je veertigste kapot aan werken voor hetzelfde resultaat.
of op zijn minst verkeerd wordt gerecycled!
anderzins je dan gaan beantwoorden wat je rond je 20ste had te vragen en
wellicht zijn alle je bekende stereotypen rond je veertigste verroest en met de populariteit bedrogen
anderzins je dan gaan beantwoorden wat je rond je 20ste had te vragen en
wellicht zijn alle je bekende stereotypen rond je veertigste verroest en met de populariteit bedrogen
vrijdag 19 november 2010
Icelanders descended from Native Americans? | Gene Expression
Icelanders descended from Native Americans? | Gene Expression: "
That is the question, and tentatively answered in the affirmative according to a new paper in The American Journal of Physical Anthropology. A new subclade of mtDNA haplogroup C1 found in icelanders: Evidence of pre-columbian contact?:
The core of the article treads the confusing gray zone between rock-hard precise science and the more vague and intuitive truths of history. One the rock-hard part, there is a huge literature on maternal genetic lineages, the mtDNA. Because this genetic material is copious it was some of the first to be analyzed using molecular clock models. A molecular clock is a feasible with mtDNA because it is haploid; it is only inherited through females and so is not subject to recombination which might break apart associations of distinctive genetic markers. Instead of being a reticulated mesh the genealogy of mtDNA is a clean and inverted elegant tree leading back to a common ancestress. You are finding the line of your mother’s mother’s mother’s mother’s….
But synthesizing this clarity with human history is more difficult, because we are dependent on the bias of text, and even more tendentious clues from oral history and archaeology. Because of Iceland’s Lutheran Christian heritage the maternal lineage here could be traced back to 1700. This does not mean that the first woman in the line that we know of was born like Athena from the head of her father; rather, the records were not kept well enough to continue unbroken back to the medieval era. We do know that the first permanent Norse settler in Iceland arrived in 874, and, that very few immigrants from Scandinavia added diversity to the gene pool after ~1000. Iceland is a small and poor island, so quickly reached its Malthusian maximum. How else to explain that Icelanders made a secondary migration to Greenland?
The most obvious explanation for the existence of the subclade of the C1 lineage is that it arrived recently. Without knowing anything else that is what you’d have assumed. But as noted above the individuals who carry it have been traced back to a common ancestor in the early 18th century; these are native Icelanders, at least if native means anything substantive. An second point which rejects recent injection of this lineage into the gene pool: the Icelanders are their own special branch of C1, C1e. The phylogenetic tree of C1 below illustrates the relationship of the branches to each other. Since the font is so small, I added in clarifying labels (from top to bottom it’s C1a to C1e, with further clades such as C1d1):
As you can see, this is mostly an Amerindian clade, with some some Asians. But, by surveying the public data they did find two individuals who were European who carried possible C1e. I’ll quote:
They believe that the Canary Islander is probably the result of admixture during the Spanish colonial era with someone who returned from the New World colonies. The German is the one to focus on. A plausible alternative model is that C1e is a very low frequency European lineage, which increased in frequency in Iceland simply through genetic drift because of that island’s small population. Remember that though C1e is rare in Iceland, its frequency is much higher than in Northern Europe as a whole. Though here we must be cautious because the typing was preliminary in the Germany case, the authors note that “This is because there are no other known human mtDNA sequences belong to C1e out of the 6747 complete sequences available in the literature.” Also, the authors observe that there is variation among the Iceland C1e lineages, mutations which differentiate them. This further tilts the playing field toward an early entrance of the lineage into Iceland, probably before Columbus, because a late arrival would not have had time to build up mutational variation in the region of Iceland where C1e is found.
As this subclade is absent among Native Americans, you may wonder as to a relationship to Greelanders or Inuit. The larger C1 haplogroup as a whole is not evident in these populations. You can inspect the geographical distribution closer yourself. If this woman was a non-European, she was not maternally related to the peoples who replaced the Norse in Greenland. Though we should also be careful about assuming that the present genetic variation in the American Arctic is representative of pre-modern variation.
If the Greenland and ancient European hypotheses are rejected, what we have is a woman who entered the Icelandic society from an extinct lineage of Native Americans, probably from the northeast (or perhaps her Greenland Norse mother was of this line). What the Norse would have termed Markland. It is tempting to point to the Norse settlement at L’Anse aux Meadows in Newfoundland. Perhaps the Europeans had enslaved a native woman, and taken her back to their homeland when they decamped? But more likely to me is the probability that the Norse brought back more than lumber from Markland, since their voyages spanned centuries.
Finally, does this explain Bjork? I doubt it. A minority of Scandinavians, especially ones of Sami background, exhibit an “Asiatic” cast to their features. The autosomal genomic content of the Icelanders is what you’d expect, Scandinavian leavened with British, and twisted with their own particular history of population bottlenecks. Only the precision of mtDNA typing brought the reality of the woman who carried C1e into the light. In terms of total genome content she is one of tens of thousands of ancestors to any given descendant, and she may be one of the less common ones in the family trees because of her likely lower status. Though the flip side of the nature of mtDNA, and the inbred aspect of the Iceland pedigree, is that probably all native Icelanders can draw many lines of descent to this woman.
Citation: Ebenesersdóttir SS, Sigurðsson A, Sánchez-Quinto F, Lalueza-Fox C, Stefánsson K, & Helgason A (2010). A new subclade of mtDNA haplogroup C1 found in icelanders: Evidence of pre-columbian contact? American journal of physical anthropology PMID: 21069749
Image Credit: Cristiano Del Riccio
"
That is the question, and tentatively answered in the affirmative according to a new paper in The American Journal of Physical Anthropology. A new subclade of mtDNA haplogroup C1 found in icelanders: Evidence of pre-columbian contact?:Although most mtDNA lineages observed in contemporary Icelanders can be traced to neighboring populations in the British Isles and Scandinavia, one may have a more distant origin. This lineage belongs to haplogroup C1, one of a handful that was involved in the settlement of the Americas around 14,000 years ago. Contrary to an initial assumption that this lineage was a recent arrival, preliminary genealogical analyses revealed that the C1 lineage was present in the Icelandic mtDNA pool at least 300 years ago. This raised the intriguing possibility that the Icelandic C1 lineage could be traced to Viking voyages to the Americas that commenced in the 10th century. In an attempt to shed further light on the entry date of the C1 lineage into the Icelandic mtDNA pool and its geographical origin, we used the deCODE Genetics genealogical database to identify additional matrilineal ancestors that carry the C1 lineage and then sequenced the complete mtDNA genome of 11 contemporary C1 carriers from four different matrilines. Our results indicate a latest possible arrival date in Iceland of just prior to 1700 and a likely arrival date centuries earlier. Most surprisingly, we demonstrate that the Icelandic C1 lineage does not belong to any of the four known Native American (C1b, C1c, and C1d) or Asian (C1a) subclades of haplogroup C1. Rather, it is presently the only known member of a new subclade, C1e. While a Native American origin seems most likely for C1e, an Asian or European origin cannot be ruled out.
The core of the article treads the confusing gray zone between rock-hard precise science and the more vague and intuitive truths of history. One the rock-hard part, there is a huge literature on maternal genetic lineages, the mtDNA. Because this genetic material is copious it was some of the first to be analyzed using molecular clock models. A molecular clock is a feasible with mtDNA because it is haploid; it is only inherited through females and so is not subject to recombination which might break apart associations of distinctive genetic markers. Instead of being a reticulated mesh the genealogy of mtDNA is a clean and inverted elegant tree leading back to a common ancestress. You are finding the line of your mother’s mother’s mother’s mother’s….
But synthesizing this clarity with human history is more difficult, because we are dependent on the bias of text, and even more tendentious clues from oral history and archaeology. Because of Iceland’s Lutheran Christian heritage the maternal lineage here could be traced back to 1700. This does not mean that the first woman in the line that we know of was born like Athena from the head of her father; rather, the records were not kept well enough to continue unbroken back to the medieval era. We do know that the first permanent Norse settler in Iceland arrived in 874, and, that very few immigrants from Scandinavia added diversity to the gene pool after ~1000. Iceland is a small and poor island, so quickly reached its Malthusian maximum. How else to explain that Icelanders made a secondary migration to Greenland?
The most obvious explanation for the existence of the subclade of the C1 lineage is that it arrived recently. Without knowing anything else that is what you’d have assumed. But as noted above the individuals who carry it have been traced back to a common ancestor in the early 18th century; these are native Icelanders, at least if native means anything substantive. An second point which rejects recent injection of this lineage into the gene pool: the Icelanders are their own special branch of C1, C1e. The phylogenetic tree of C1 below illustrates the relationship of the branches to each other. Since the font is so small, I added in clarifying labels (from top to bottom it’s C1a to C1e, with further clades such as C1d1):
As you can see, this is mostly an Amerindian clade, with some some Asians. But, by surveying the public data they did find two individuals who were European who carried possible C1e. I’ll quote:
…, using the criteria of one mutational difference from C1e when sequences were avail- able for only hypervariable segment 1 (HVS1) or 2 (HVS2) and two mutational differences when both HVS1 and HVS2 sequences were available. The result was a shortlist of 276 sequences that we suggest be checked first for C1e coding region mutations (Supp. Info. Table S3). We note that for the sequences for which geographical information is available, all but two were sampled from individuals with Native American ancestry—i.e. from the Canary Islands and Germany.
The German sequence…represents a perfect match to the Icelandic C1e for the short HVS1 fragment spanning sites 16024–16365. This raises the intriguing, but perhaps unlikely, hypothesis that C1e is a European-specific subclade of C1, following the precedent of the European and Native American subclades of mtDNA haplogroup X2…However, given the dense sampling of mtDNA variation in European populations, it is clear that C1e is exceedingly rare, a fact that weighs against a hypothesis of antiquity in Europe.
They believe that the Canary Islander is probably the result of admixture during the Spanish colonial era with someone who returned from the New World colonies. The German is the one to focus on. A plausible alternative model is that C1e is a very low frequency European lineage, which increased in frequency in Iceland simply through genetic drift because of that island’s small population. Remember that though C1e is rare in Iceland, its frequency is much higher than in Northern Europe as a whole. Though here we must be cautious because the typing was preliminary in the Germany case, the authors note that “This is because there are no other known human mtDNA sequences belong to C1e out of the 6747 complete sequences available in the literature.” Also, the authors observe that there is variation among the Iceland C1e lineages, mutations which differentiate them. This further tilts the playing field toward an early entrance of the lineage into Iceland, probably before Columbus, because a late arrival would not have had time to build up mutational variation in the region of Iceland where C1e is found.
As this subclade is absent among Native Americans, you may wonder as to a relationship to Greelanders or Inuit. The larger C1 haplogroup as a whole is not evident in these populations. You can inspect the geographical distribution closer yourself. If this woman was a non-European, she was not maternally related to the peoples who replaced the Norse in Greenland. Though we should also be careful about assuming that the present genetic variation in the American Arctic is representative of pre-modern variation.If the Greenland and ancient European hypotheses are rejected, what we have is a woman who entered the Icelandic society from an extinct lineage of Native Americans, probably from the northeast (or perhaps her Greenland Norse mother was of this line). What the Norse would have termed Markland. It is tempting to point to the Norse settlement at L’Anse aux Meadows in Newfoundland. Perhaps the Europeans had enslaved a native woman, and taken her back to their homeland when they decamped? But more likely to me is the probability that the Norse brought back more than lumber from Markland, since their voyages spanned centuries.
Finally, does this explain Bjork? I doubt it. A minority of Scandinavians, especially ones of Sami background, exhibit an “Asiatic” cast to their features. The autosomal genomic content of the Icelanders is what you’d expect, Scandinavian leavened with British, and twisted with their own particular history of population bottlenecks. Only the precision of mtDNA typing brought the reality of the woman who carried C1e into the light. In terms of total genome content she is one of tens of thousands of ancestors to any given descendant, and she may be one of the less common ones in the family trees because of her likely lower status. Though the flip side of the nature of mtDNA, and the inbred aspect of the Iceland pedigree, is that probably all native Icelanders can draw many lines of descent to this woman.
Citation: Ebenesersdóttir SS, Sigurðsson A, Sánchez-Quinto F, Lalueza-Fox C, Stefánsson K, & Helgason A (2010). A new subclade of mtDNA haplogroup C1 found in icelanders: Evidence of pre-columbian contact? American journal of physical anthropology PMID: 21069749
Image Credit: Cristiano Del Riccio
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dinsdag 16 november 2010
middelpunt
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De aarde is niet het middelpunt van ons zonnestelsel
het zonnestelsel is niet het middelpunt van de melkweg
de melkweg niet het middelpunt van het bekende universum
het hele melkwegstelsel draait rond een super zwaar zwart gat
en de materie waaruit de mens bestaat is niet het hoofdbestanddeel van het universum
De mens is bijprodukt, is dat dan niet hetzelfde als ons inzicht in god?
Maar aan de stroom absurditeiten, sadisme en rampberichten op internet te beoordelen kan god niet bestaan.
Mocht je domineeskinderen kennen, dan weet je dat duivelsgebroed echter wel bestaat.
"De aarde is niet het middelpunt van ons zonnestelsel
het zonnestelsel is niet het middelpunt van de melkweg
de melkweg niet het middelpunt van het bekende universum
het hele melkwegstelsel draait rond een super zwaar zwart gat
en de materie waaruit de mens bestaat is niet het hoofdbestanddeel van het universum
De mens is bijprodukt, is dat dan niet hetzelfde als ons inzicht in god?
Maar aan de stroom absurditeiten, sadisme en rampberichten op internet te beoordelen kan god niet bestaan.
Mocht je domineeskinderen kennen, dan weet je dat duivelsgebroed echter wel bestaat.
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