Price - Revision history

Julian.garcia: /* Extra links */

2011-10-20T08:30:17Z

Extra links

← Older revision		Revision as of 08:30, 20 October 2011
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	== Extra links ==		== Extra links ==
		+	* Please check the paper '''Group selection and inclusive fitness are not equivalent; the Price equation vs. models and statistics'''. van Veelen, Garcia, Egas, Sabellis. In press. It is about the use of the price equation and the theory of inclusive fitness. [http://www.sciencedirect.com/science/article/pii/S0022519311003754 Link]

	* John Maynard Smith [http://www.webofstories.com/play/7297 talks about the Price equation] and how this approach always felt unnatural to him. Since some of us remember a feeling of doubt when first confronted with the Price equation, it may be a relief to hear him say 'I'm not going to tell you what Price's theorem is, because I don't actually understand it'.		* John Maynard Smith [http://www.webofstories.com/play/7297 talks about the Price equation] and how this approach always felt unnatural to him. Since some of us remember a feeling of doubt when first confronted with the Price equation, it may be a relief to hear him say 'I'm not going to tell you what Price's theorem is, because I don't actually understand it'.

Julian.garcia at 11:07, 9 October 2010

2010-10-09T11:07:48Z

← Older revision		Revision as of 11:07, 9 October 2010
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	The Price equation zooms in on transitions from one generation to the next. This suggests that it could be a fundamental tool for understanding this		The Price equation zooms in on transitions from one generation to the next. This suggests that it could be a fundamental tool for understanding this
-	process of evolution. It was formulated by George Richard Price in 1970 [http://www.nature.com/nature/journal/v227/n5257/abs/227520a0.html in an article in Nature], and acclaimed by some, maybe even quite a few, to be a fundamental ingredient for models of evolution ([http://dx.doi.org/10.1016/j.cub.2008.01.005 Gardner], [http://dx.doi.org/10.1006/jtbi.1995.0148 Frank], [http://dx.doi.org/10.1006/jtbi.2002.3015 Grafen]). We think not. The reason why it is hard to identify it as such is that it is all about probability theory and statistics, and those two topics are just not that easy. The following tutorial will help by looking at what proper probability theory or statistics would do and compare that to what the Price equation does to numbers that represent those transitions. There is [http://dx.doi.org/10.1016/j.jtbi.2005.04.026 an article with the same message], but this tutorial makes it simpler, by allowing you to play around with models, data and samples yourself. At some points you may find that the steps the tutorial takes are evident and all too easy, but it is possible that after a few steps, as simple as they are, you may nonetheless feel confused enough to make you want to retrace your steps and be happy, the second time around, that they are that simple. Or not~~, in which~~ case you will just have an easy journey to a deep understanding why the Price equation is not what some say it is.	+	process of evolution. It was formulated by George Richard Price in 1970 [http://www.nature.com/nature/journal/v227/n5257/abs/227520a0.html in an article in Nature], and acclaimed by some, maybe even quite a few, to be a fundamental ingredient for models of evolution ([http://dx.doi.org/10.1016/j.cub.2008.01.005 Gardner], [http://dx.doi.org/10.1006/jtbi.1995.0148 Frank], [http://dx.doi.org/10.1006/jtbi.2002.3015 Grafen]). We think not. The reason why it is hard to identify it as such is that it is all about probability theory and statistics, and those two topics are just not that easy. The following tutorial will help by looking at what proper probability theory or statistics would do and compare that to what the Price equation does to numbers that represent those transitions. There is [http://dx.doi.org/10.1016/j.jtbi.2005.04.026 an article with the same message], but this tutorial makes it simpler, by allowing you to play around with models, data and samples yourself. At some points you may find that the steps the tutorial takes are evident and all too easy, but it is possible that after a few steps, as simple as they are, you may nonetheless feel confused enough to make you want to retrace your steps and be happy, the second time around, that they are that simple. If this is not the case you will just have an easy journey to a deep understanding of why the Price equation is not what some say it is.

	==Price 1.0: A very simple model ==		==Price 1.0: A very simple model ==
	We will begin with the simplest real model that we can think of. No sex, no shrinking or expanding populations, no frequency dependence, no		We will begin with the simplest real model that we can think of. No sex, no shrinking or expanding populations, no frequency dependence, no
	complications whatsoever. Just two individuals that are ready to reproduce. Asexually. This gives us a version of the Price equation that is even		complications whatsoever. Just two individuals that are ready to reproduce. Asexually. This gives us a version of the Price equation that is even
-	simpler than the first version by Price himself. And it will give us probability theory and statistics that is relatively nice and easy too, and therefore an excellent start ~~that helps us get acquainted to the joys of rigour and precision~~.	+	simpler than the first version by Price himself. And it will give us probability theory and statistics that is relatively nice and easy too, and therefore an excellent start.

	[[Price 1.0 \| Go to the Tutorial ]]		[[Price 1.0 \| Go to the Tutorial ]]
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	== Price 3.0: A model with frequency dependence ==		== Price 3.0: A model with frequency dependence ==

-	We go back to the asexual model, but now we will take a model with frequency dependence. This will be a bit more complicated, but we can still use a basic, well known model. ~~They~~ are ~~paired~~ randomly~~, and~~ play a game ~~in those pairs~~. The game gives them payoffs according to a payoff matrix	+	We go back to the asexual model, but now we will take a model with frequency dependence. This will be a bit more complicated, but we can still use a basic, well known model. Individuals are randomly paired to play a game. The game gives them payoffs according to a payoff matrix

	[[Price 3.0 \| Go to the Tutorial ]]		[[Price 3.0 \| Go to the Tutorial ]]

Julian.garcia: /* Extra links */

2010-10-04T19:44:55Z

Extra links

← Older revision		Revision as of 19:44, 4 October 2010
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	== Extra links ==		== Extra links ==

-	* John Maynard Smith [http://www.webofstories.com/play/7297 talks about the Price equation] and how this approach always felt unnatural to him. Since ~~most~~ of us remember a feeling of doubt when first confronted with the Price equation, it may be a relief to hear him say 'I'm not going to tell you what Price's theorem is, because I don't actually understand it'.	+	* John Maynard Smith [http://www.webofstories.com/play/7297 talks about the Price equation] and how this approach always felt unnatural to him. Since some of us remember a feeling of doubt when first confronted with the Price equation, it may be a relief to hear him say 'I'm not going to tell you what Price's theorem is, because I don't actually understand it'.

Julian.garcia at 17:13, 4 October 2010

2010-10-04T17:13:03Z

← Older revision		Revision as of 17:13, 4 October 2010
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	[[Price 3.0 Applet \| Go straight to the software]]		[[Price 3.0 Applet \| Go straight to the software]]
-

	== Extra links ==		== Extra links ==

	* John Maynard Smith [http://www.webofstories.com/play/7297 talks about the Price equation] and how this approach always felt unnatural to him. Since most of us remember a feeling of doubt when first confronted with the Price equation, it may be a relief to hear him say 'I'm not going to tell you what Price's theorem is, because I don't actually understand it'.		* John Maynard Smith [http://www.webofstories.com/play/7297 talks about the Price equation] and how this approach always felt unnatural to him. Since most of us remember a feeling of doubt when first confronted with the Price equation, it may be a relief to hear him say 'I'm not going to tell you what Price's theorem is, because I don't actually understand it'.

Matthijs.van.veelen: /* Extra links */

2010-10-04T16:58:23Z

Extra links

← Older revision		Revision as of 16:58, 4 October 2010
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	== Extra links ==		== Extra links ==

-	* John Maynard Smith [http://www.webofstories.com/play/7297 talks about the Price equation] and how this approach always felt unnatural to him. Since most of us remember a feeling of doubt ~~about~~ the Price equation, it may be a relief to hear him say 'I'm not going to tell you what Price's theorem is, because I don't actually understand it'.	+	* John Maynard Smith [http://www.webofstories.com/play/7297 talks about the Price equation] and how this approach always felt unnatural to him. Since most of us remember a feeling of doubt when first confronted with the Price equation, it may be a relief to hear him say 'I'm not going to tell you what Price's theorem is, because I don't actually understand it'.

Matthijs.van.veelen: /* Extra links */

2010-10-04T16:57:31Z

Extra links

← Older revision		Revision as of 16:57, 4 October 2010
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	== Extra links ==		== Extra links ==

-	* John Maynard Smith [http://www.webofstories.com/play/7297 talks about the Price equation] and how this approach always felt unnatural to him.	+	* John Maynard Smith [http://www.webofstories.com/play/7297 talks about the Price equation] and how this approach always felt unnatural to him. Since most of us remember a feeling of doubt about the Price equation, it may be a relief to hear him say 'I'm not going to tell you what Price's theorem is, because I don't actually understand it'.

Julian.garcia at 13:25, 4 October 2010

2010-10-04T13:25:21Z

← Older revision		Revision as of 13:25, 4 October 2010
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	[[Price 3.0 Applet \| Go straight to the software]]		[[Price 3.0 Applet \| Go straight to the software]]
		+
		+
		+	== Extra links ==
		+
		+	* John Maynard Smith [http://www.webofstories.com/play/7297 talks about the Price equation] and how this approach always felt unnatural to him.

Julian.garcia: /* Introduction */

2010-10-04T13:22:43Z

Introduction

← Older revision		Revision as of 13:22, 4 October 2010
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	== Introduction ==		== Introduction ==

-	Evolution is all about transitions. One generation gives birth to the next, which gives birth to yet another generation, in an endless chain of transitions. These transitions don't just go anywhere; some transitions are more likely than others. First of all we beget offspring that is likely to bear some similarity with ourselves. And how likely we are to get offspring at all, and how many, tends to depend on certain heritable characteristics. The relative likelihood of some transitions and the relative improbability of others imply that we can make informed guesses as to where this endless chain of transitions came from and where it is going~~. That is what the science of evolution does~~.	+	Evolution is all about transitions. One generation gives birth to the next, which gives birth to yet another generation, in an endless chain of transitions. These transitions don't just go anywhere; some transitions are more likely than others. First of all we beget offspring that is likely to bear some similarity with ourselves. And how likely we are to get offspring at all, and how many, tends to depend on certain heritable characteristics. The relative likelihood of some transitions and the relative improbability of others imply that we can make informed guesses as to where this endless chain of transitions came from and where it is going.

	The Price equation zooms in on transitions from one generation to the next. This suggests that it could be a fundamental tool for understanding this		The Price equation zooms in on transitions from one generation to the next. This suggests that it could be a fundamental tool for understanding this
-	process of evolution. It was formulated by George Richard Price in 1970 [http://www.nature.com/nature/journal/v227/n5257/abs/227520a0.html in an article in Nature], and acclaimed by some, maybe even quite a few, to be a fundamental ingredient for models of evolution ([http://dx.doi.org/10.1016/j.cub.2008.01.005 Gardner], [http://dx.doi.org/10.1006/jtbi.1995.0148 Frank], [http://dx.doi.org/10.1006/jtbi.2002.3015 Grafen]). We think not~~. We think it is an unintended hoax~~. The reason why it is hard to identify it as such is that it is all about probability theory and statistics, and those two topics are just not that easy. The following tutorial will help by looking at what proper probability theory or statistics would do and compare that to what the Price equation does to numbers that represent those transitions. There is [http://dx.doi.org/10.1016/j.jtbi.2005.04.026 an article with the same message], but this tutorial makes it simpler, by allowing you to play around with models, data and samples yourself. At some points you may find that the steps the tutorial takes are evident and all too easy, but it is possible that after a few steps, as simple as they are, you may nonetheless feel confused enough to make you want to retrace your steps and be happy, the second time around, that they are that simple. Or not, in which case you will just have an easy journey to a deep understanding why the Price equation is not what some say it is.	+	process of evolution. It was formulated by George Richard Price in 1970 [http://www.nature.com/nature/journal/v227/n5257/abs/227520a0.html in an article in Nature], and acclaimed by some, maybe even quite a few, to be a fundamental ingredient for models of evolution ([http://dx.doi.org/10.1016/j.cub.2008.01.005 Gardner], [http://dx.doi.org/10.1006/jtbi.1995.0148 Frank], [http://dx.doi.org/10.1006/jtbi.2002.3015 Grafen]). We think not. The reason why it is hard to identify it as such is that it is all about probability theory and statistics, and those two topics are just not that easy. The following tutorial will help by looking at what proper probability theory or statistics would do and compare that to what the Price equation does to numbers that represent those transitions. There is [http://dx.doi.org/10.1016/j.jtbi.2005.04.026 an article with the same message], but this tutorial makes it simpler, by allowing you to play around with models, data and samples yourself. At some points you may find that the steps the tutorial takes are evident and all too easy, but it is possible that after a few steps, as simple as they are, you may nonetheless feel confused enough to make you want to retrace your steps and be happy, the second time around, that they are that simple. Or not, in which case you will just have an easy journey to a deep understanding why the Price equation is not what some say it is.

	==Price 1.0: A very simple model ==		==Price 1.0: A very simple model ==

Matthijs.van.veelen: /* Price 2.0: A model with sexual reproduction */

2010-09-20T10:57:17Z

Price 2.0: A model with sexual reproduction

← Older revision		Revision as of 10:57, 20 September 2010
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	If we add sexual reproduction, everything gets slightly more complicated, the proper statistics as well as the Price equation. This makes		If we add sexual reproduction, everything gets slightly more complicated, the proper statistics as well as the Price equation. This makes
-	the statistics much more fun, and it makes the failure of the Price equation to be of any help even more salient. We like to keep it relatively simple though, so for the moment we do not assume actual different sexes, but we do assume that every individual is diploid	+	the statistics much more fun, and it makes the failure of the Price equation to be of any help even more salient. We like to keep it relatively simple though, so for the moment we do not assume actual different sexes, but we do assume that every individual is diploid.

	[[Price 2.0 \| Go to the Tutorial ]]		[[Price 2.0 \| Go to the Tutorial ]]

Matthijs.van.veelen: /* Introduction */

2010-09-20T10:40:33Z

Introduction

← Older revision		Revision as of 10:40, 20 September 2010
Line 6:		Line 6:

	The Price equation zooms in on transitions from one generation to the next. This suggests that it could be a fundamental tool for understanding this		The Price equation zooms in on transitions from one generation to the next. This suggests that it could be a fundamental tool for understanding this
-	process of evolution. It was formulated by George Richard Price in 1970 [http://www.nature.com/nature/journal/v227/n5257/abs/227520a0.html in an article in Nature], and acclaimed by some, maybe even quite a few, to be a fundamental ingredient for models of evolution ([http://dx.doi.org/10.1016/j.cub.2008.01.005 Gardner], [http://dx.doi.org/10.1006/jtbi.1995.0148 Frank], Grafen). We think not. We think it is an unintended hoax. The reason why it is hard to identify it as such is that it is all about probability theory and statistics, and those two topics are just not that easy. The following tutorial will help by looking at what proper probability theory or statistics would do and compare that to what the Price equation does to numbers that represent those transitions. There is [http://dx.doi.org/10.1016/j.jtbi.2005.04.026 an article with the same message], but this tutorial makes it simpler, by allowing you to play around with models, data and samples yourself. At some points you may find that the steps the tutorial takes are evident and all too easy, but it is possible that after a few steps, as simple as they are, you may nonetheless feel confused enough to make you want to retrace your steps and be happy, the second time around, that they are that simple. Or not, in which case you will just have an easy journey to a deep understanding why the Price equation is not what some say it is.	+	process of evolution. It was formulated by George Richard Price in 1970 [http://www.nature.com/nature/journal/v227/n5257/abs/227520a0.html in an article in Nature], and acclaimed by some, maybe even quite a few, to be a fundamental ingredient for models of evolution ([http://dx.doi.org/10.1016/j.cub.2008.01.005 Gardner], [http://dx.doi.org/10.1006/jtbi.1995.0148 Frank], [http://dx.doi.org/10.1006/jtbi.2002.3015 Grafen]). We think not. We think it is an unintended hoax. The reason why it is hard to identify it as such is that it is all about probability theory and statistics, and those two topics are just not that easy. The following tutorial will help by looking at what proper probability theory or statistics would do and compare that to what the Price equation does to numbers that represent those transitions. There is [http://dx.doi.org/10.1016/j.jtbi.2005.04.026 an article with the same message], but this tutorial makes it simpler, by allowing you to play around with models, data and samples yourself. At some points you may find that the steps the tutorial takes are evident and all too easy, but it is possible that after a few steps, as simple as they are, you may nonetheless feel confused enough to make you want to retrace your steps and be happy, the second time around, that they are that simple. Or not, in which case you will just have an easy journey to a deep understanding why the Price equation is not what some say it is.

	==Price 1.0: A very simple model ==		==Price 1.0: A very simple model ==