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- 1 Is it plagiarism?
- 2 rational expectations is a hypothesis or modeling technique, not a theory
- 3 'Equilibrium' can mean steady state, or can mean mutual consistency of decisions
- 4 First sentence
- 5 Look out for possible copyright violations in this article
- 6 Definition not encyclopedic style
- 7 Dr. Davila's comment on this article
- 8 Possible extension to this article
- 9 Reflexive events and full blown rational expectations
- 10 Unsourced and off-topic OR deleted from the article
- 11 Criticisms
- 12 Vandalism in deleting material from the article
Is it plagiarism?
This page was basically copied and pasted from its external link.
Foraday 16:52, 26 March 2007 (UTC)
rational expectations is a hypothesis or modeling technique, not a theory
It is not even a model, it is an assumption used to derive the expectations term of a model, and so can be (and has been) applied to many different models. The intuition is, if the error term was not symmetrically distributed with a mean of zero, systematic profit opportunities exist. If the opportunities are discoverable, they will be exploited, eliminating the systematic bias and revalidating the original assumption. — Preceding unsigned comment added by 188.8.131.52 (talk) 06:28, 5 December 2012 (UTC)
- Yes, these are good points. As it stands now, some of the article reads like a defense of something, like the efficient market hypothesis, when these things are distinctly separate. I will see if I can do a few edits to clean some of this up. Nwlaw63 (talk) 15:14, 16 January 2015 (UTC)
'Equilibrium' can mean steady state, or can mean mutual consistency of decisions
No equilibrium means that nothing changes with time in a deterministic system. This is simply time translational invariance. In stochastic dynamics equilibrium, time translational invariance, means that the 1-point density, hence all 1-point averages (the mean, variance, any moment) are constants independent of time t. For higher order densities and correlations it means independence of the present time t, and dependence only on the lag time T. all other 'definitions' of equilibrium are wrong, are simply fudges invented to try to save the face of neo-classical econ and ratex. — Preceding unsigned comment added by 184.108.40.206 (talk) 17:59, 13 May 2012 (UTC)
I am removing (for the second time) a sequence of assertions by user jmccauley, who claims that rational expectations involves a misunderstanding of the concept of equilibrium. The text I removed is shown below:
- The basis for the rational expectations model is based on a mathematical inconsistency (in Muth, 1961): a time varying price is derived from the assumption of market equilibrium. Equilibrium means time translationalinvariance, simple averages cannot change with time. Muth's (and Lucas's and Sargent's) violation of the definition of equilibrium is common in the economics and finance literature. For the correct definition of equilibrium (dynamic or statistical) see texts on ordinary diffeential equations, dynamical systems, statistical physics, or stochastic processes. Lucas tried to maintain the essence of neo-classical ideology by attempting to define away nonstationary processes, but this resulted only in self-organized confusion, not understanding of markets. Finance markets (and presumably all other markets) are nonstationary, are far from equilibrium, and all attempts by economists to understand and explain markets have failed.
- 1. J.L. McCauley, K.E. Bassler, and G.H. Gunaratne, Martingales, Detranding Data, and the Efficient Market Hypothesis, Physica A37, 202, 2008.
- 2. K.E. Bassler, J. L. McCauley, & G.H. Gunaratne, Nonstationary Increments, Scaling Distributions, and Variable Diffusion Processes in Financial Markets, PNAS 104, 17297, 23 Oct. 2007.
This text asserts that 'equilibrium' refers to a system which is not changing over time. Many years ago, this was indeed the usual meaning of equilibrium in economics. But today, most economists use the word 'equilibrium' in a different sense, essentially the same way it is used in game theory: mutual consistency between agents' decisions. Economists do not claim to use the word in the same way statistical physicists use it.
The whole point of the rational expectations revolution was that some earlier adaptive expectations models implied behavior that was far from optimal. Imposing rational expectations means that agents know how the economy behaves, and make their decisions optimally taking this knowledge into account. In other words, the expectations on which agents base their decisions are consistent with the actual behavior of the economy. That is equilibrium in (roughly speaking) the sense of Nash. It is NOT equilibrium in the sense of statistical physics: there is no assumption that the economy is behaving in a constant way over time. An economic situation that is unchanging over time is nowadays usually called a 'steady state', which is NOT a synonym for 'equilibrium' in the Nash sense of the word. --Rinconsoleao (talk) 14:42, 26 December 2007 (UTC)
The basis for the rational expectations model is based on a mathematical inconsistency (in Muth, 1961): a time varying price is derived from the assumption of market equilibrium. Equilibrium means time translationalinvariance, simple averages cannot change with time. Muth's (and Lucas's and Sargent's) violation of the definition of equilibrium is common in the economics and finance literature. For the correct definition of equilibrium (dynamic or statistical) see texts on ordinary diffeential equations, dynamical systems, statistical physics, or stochastic processes. Lucas tried to maintain the essence of neo-classical ideology by attempting to define away nonstationary processes, but this resulted only in self-organized confusion, not understanding of markets. Finance markets (and presumably all other markets) are nonstationary, are far from equilibrium, and all attempts by economists to understand and explain markets have failed.
References: 1. J.L. McCauley, K.E. Bassler, and G.H. Gunaratne, Martingales, Detranding Data, and the Efficient Market Hypothesis, Physica A37, 202, 2008.
2. K.E. Bassler, J. L. McCauley, & G.H. Gunaratne, Nonstationary Increments, Scaling Distributions, and Variable Diffusion Processes in Financial Markets, PNAS 104, 17297, 23 Oct. 2007.
This article is suffering from excessive disclaimerism: its writing is so concerned with avoid misinterpretation that it's not being direct, succinct, and readable. I recommend that the first sentence in particular make some stab at a definition of rational expectations, rather than giving a detailed contextualization without even mentioning what the term means. The article is showing the effects of a contentious editing process, but that process should end with a nuanced and appropriate re-writing. And, I would do it myself, if I didn't have the apparently, woefully incorrect assumption that rational expectations meant that people were perfectly rational/utility optimizers in their decision making.220.127.116.11 (talk) 10:52, 17 January 2010 (UTC)
- That's Wikipedia's mode of operating. A bunch of useless editing and petty fights between pseudo-intellectuals who finally culminates into a bunch of sentences that are so crappy it's embarrassing. —Preceding unsigned comment added by 18.104.22.168 (talk) 05:34, 5 February 2010 (UTC)
Look out for possible copyright violations in this article
This article has been found to be edited by students of the Wikipedia:India Education Program project as part of their (still ongoing) course-work. Unfortunately, many of the edits in this program so far have been identified as plain copy-jobs from books and online resources and therefore had to be reverted. See the India Education Program talk page for details. In order to maintain the WP standards and policies, let's all have a careful eye on this and other related articles to ensure that no material violating copyrights remains in here. --Matthiaspaul (talk) 12:34, 1 November 2011 (UTC)
Definition not encyclopedic style
A term should be defined by indicating what it means, not what it implies. No one would define a first derivative as something that must vanish in an optimum. I change the definition accordingly.--Herbert81 (talk) 17:42, 14 October 2015 (UTC)
@Buldri: Are you serious with your second revert? It is encyclopedic style to define something by stating what it is rather than by an indication of its usefulness or by arguable characteristics. A rational expectation is an expected value in the mathematical sense. Fullstop. I wouldn't bother if you put it in the plural but the indirect characterization you offer is unacceptable. --Herbert81 (talk) 17:39, 18 October 2015 (UTC)
@Herbert81: Please take a more serious tone. First, if you had bothered reading what you just removed you would have seen that it defined "rational expectations" by what the terms means. Second, if you had any insight into the topic of this article you would maybe have realized that it is not about the mathematical definition of "a rational expectation", but about the economic concept "rational expectations". Buldri (talk) 21:50, 18 October 2015 (UTC)
@Buldri: "Defining" rational expectations as model consistent expectations is circular. To define rational expectations as mathematical expected values is preferable because an expected value is precisely defined in mathematics. I do not understand what you mean by "economic concept" as opposed to a mathematical definition. Perhaps someone else should consider this exchange.--Herbert81 (talk) 09:53, 19 October 2015 (UTC)
Dr. Davila's comment on this article
Dr. Davila has reviewed this Wikipedia page, and provided us with the following comments to improve its quality:
too vague/imprecise/lacking focus
one could think that this reflects the very historical development of the concept, which was plagued with misconceptions and corrections, back and forth, but it is wrong to present it nowadays with all that noise. it makes a disservice to students.
the RE assumption is a just consistency requirement between the expectations held by optimisers about some value(s) influenced by their choices (based on those expectations) and the values actually implied by their choices. Should the two things not be the same, the agents would exhibit some kind of irrationality/arbitrariness in holding those expectations, or they don't understand the consequences of their choices. Be as it may, if expectations are nor "rational" (in the sense of the RE assumption), agents are not rational, and that just leads to another paradigm which is not that of 99% of economics, for many good reasons (and some bad ones).
We hope Wikipedians on this talk page can take advantage of these comments and improve the quality of the article accordingly.
We believe Dr. Davila has expertise on the topic of this article, since he has published relevant scholarly research:
- Reference : The Rationality of Expectations Formation, The B.E. Journal of Theoretical Economics 16(2), 515-543 (2016)
Possible extension to this article
This article should have a more wider perspective than it currently has. This is the question of framing the Rational Expectations in a larger phenomenon called biopolitics. The core of biopolitics is a claim that governance can be done using more hidden tools than the tools of modern democracy. This is actually the claim known as 'Hayek's crystal'. Hayek uses the word 'law' to refer both legislation and a law of nature. David Hume has explained this with the claim that a human being can not be without expecting. Hume has also pointed out that this is a question of 'human nature'. Human nature is not limited to expectation.
Rational Expectations does not empty the concept of biopolitics in economics or Hume's notion about human nature. It leaves outside a vast domain that is both known and unknown at the same time. The environment we live today includes the synthetic environment of electrical devices. These tools have been a remarkable part of the modern era. The difference is that the current low voltage systems are the product of the postmodern era. This difference should be highlighted. The devices that measure our heartbeat etc. have been in the market for a long time and the technology has been advancing fast. There are now devices that are more or less implants to human bodies and connected to the nervous system. But still electricity is understood as separate from a human body and we are living at the same time in the middle of the wireless communications systems' signals.
Rational Expectations is not only a feature in economics. It is a model of governance. This article about Rational Expectations has been updated with minor constraints. This implies that Rational Expectations is no more the focus of economics but on the contrary. The expectations are currently so crudely utilized in the political discourse focused on so-called sound economic policies, that it seems to be the very intention to blow the expectations out of the toolbox of economics. This would lead more or less to the state of what is called Pyrrhomism that Hume saw as to be prohibited. How can the powerholders allow this to happen? The explanation is that there is an alternative paradigm of governance. The weakness of Rational Expectations is that metacognition can be a major obstacle for it. Therefore the focus of the investigation should be in unconscious processes.
There is the major problem that the focus on expectations leads to skepticism to expectations in general. This can damage the modern institutions that are operating on discourses, such as the parliamentary system. Focusing on expectations can in fact damage the democracy at the same time economics has established a beeper biological base.Dancing Mickey Mouse (talk) 22:50, 21 September 2016 (UTC)
Reflexive events and full blown rational expectations
These details describing reflexive events using full-blown rational expectations are alarming. Soros states that the hypothesis is not valid for these events all the time. This is actually a repeat of the famous claim that "You can fool all the people some of the time and some of the people all the time, but you cannot fool all the people all the time".
I interpret Soros' claim that using full-blown rational expectations of this kind all the time is not possible, but it is possible to use these now and then. In addition to this there is the possibility to use these in different geographical locations. What is needed is that people have trust on the people using them. Burdekin and Langdana claim that one of the key components in RE is trust. This should be absent in the world of game theory but most of the people are not aware of it.
The RE does not require that all people buy the predictions (induced expectations) and RE does not require it. The operators themselves do not buy them. There has been in the literature the concept "emotional attack". This describes well what happened in in 2001. What happened was also a prime example of Milton and Rose Friedman's Free to Choose claim about the usefulness of television regarding the emotions.
The Soros 1998 book includes a claim that the political stage of the United States has to be rearranged. He also referred to the reflexivity of Greek drama in it. In addition to that he demanded there the usage of full-blown rational expectations. Soros' Open Society organizations work still around the world and these organizations did not cease to exist after the coups in the socialist countries.
An interesting detail is that this 1998 book cover does not simply read "The Crisis of Global Capitalism". Little, Brown and Company 1998 print reads "The Crisis George of Global Soros Capitalism": http://www.alibris.co.uk/The-Crisis-of-Global-Capitalism-Open-Society-Endangered-George-Soros/book/1398212? Who is Crisis George?Dancing Mickey Mouse (talk) 21:27, 23 September 2016 (UTC)
Unsourced and off-topic OR deleted from the article
|Moved here for reference|
|The following discussion has been closed. Please do not modify it.|
Rational expectations are expected values in the mathematical sense. In order to be able to compute expected values, individuals must know the true economic model, its parameters, and the nature of the stochastic processes that govern its evolution. If these extreme assumptions are violated, individuals simply cannot form rational expectations
The models of Muth and Lucas (and the strongest version of the efficient-market hypothesis) assume that at any specific time, a market or the economy has only one equilibrium (which was determined ahead of time), so that people form their expectations around this unique equilibrium. Muth's math (sketched above) assumed that P* was unique. Lucas assumed that equilibrium corresponded to a unique "full employment" level (potential output) – corresponding to a unique NAIRU or natural rate of unemployment. If there is more than one possible equilibrium at any time then the more interesting implications of the theory of rational expectations do not apply. In fact, expectations would determine the nature of the equilibrium attained, reversing the line of causation posited by rational expectations economists.
A further problem relates to the application of the rational expectations hypothesis to aggregate behavior. It is well known that assumptions about individual behavior do not carry over to aggregate behavior (Sonnenschein-Mantel-Debreu theorem). The same holds true for rationality assumptions: Even if all individuals have rational expectations, the representative household describing these behaviors may exhibit behavior that does not satisfy rationality assumptions (Janssen 1993). Hence the rational expectations hypothesis, as applied to the representative household, is unrelated to the presence or absence of rational expectations on the micro level and lacks, in this sense, a microeconomic foundation.
It can be argued that it is difficult to apply the standard efficient-market hypothesis (efficient market theory) to understand the stock market bubble that ended in 2000 and collapsed thereafter; however, advocates[who?] of rational expectations say that the problem of ascertaining all the pertinent effects of the stock-market crash is a great challenge.
Furthermore, social scientists have criticized the movement of rational choice theory into other fields such as political science. In his book Essence of Decision, political scientist Graham T. Allison specifically attacked applications of rational choice theory. This should not be confused with rational expectations theory.
Some economists now use the adaptive expectations model, but then complement it with ideas based on the rational expectations theory. For example, an anti-inflation campaign by the central bank is more effective if it is seen as "credible," i.e., if it convinces people that it will "stick to its guns." The bank can convince people to lower their inflationary expectations, which implies less of a feedback into the actual inflation rate. (An advocate of Rational Expectations would say, rather, that the pronouncements of central banks are facts that must be incorporated into one's forecast because central banks can act independently). Those studying financial markets similarly apply the efficient-markets hypothesis but keep the existence of exceptions in mind.
Maurice Allais’s Hereditary, Relativist and Logistic (HRL) theory of monetary dynamics contains an original theory of expectations formation that is a genuine alternative to both adaptive and rational expectations. Praised by Milton Friedman in 1968 with the following words: This work [the HRL formulation] introduces a very basic and important distinction between psychological time and chronological time. It is one of the most important and original paper that has been written for a long time … for its consideration of the problem of the formation of expectations.” Allais’s contribution has nevertheless been “lost”: it has been absent from the debate about expectations.
Milton Friedman and his followers claim that rational expectations lead to the situation where government policies are ineffective. This is the message of Lucas critique and works of other new classical economists, like Henri Theil. The problem with these simplified claims is that these claims concern the decisions of actors who use metacognition about expectations, and do not operate on simple expectations. The decisions are rather based on interests and lead to interpret Friedman's and Lucas work, among others, normative, political and less scientific. Finn E. Kydland's and Edward Prescott's (1977) article Rules Rather Than Discretion: The Inconsistency of Optimal Plans shows this quite straightforward, even if the article is dressed in rational expectations jargon and warnings about government decisions which are unpleasant to the moneyed class, using Thorstein Veblen's terminology. Instead of rational expectations, it is more appropriate to describe these decisions by metacognitive mind as the decisions of an epistemic community. The epistemic community utilizes the linguistic division of labor to reach it's private goal. Hilary Putnam has claimed that the existence of linguistic division of labor can be eliminated.
George Soros provides concrete arguments that clarify the metacognition and linguistic division of labor elimination arguments with reference to Karl Popper, in his The Crisis of Global Capitalism: Open Society Endangered (pp. 30–31):
This Soros' argument mixes to different things. The citation makes sense, but it does so in the context where the falsification is not known. It is two different things to (1) have a hypothesis that is not falsified and (2) have a hypothesis with the knowledge that it can be falsified. Soros continues:
This citation shows that Soros refers to falsifiable hypotheses. It is again two different things to (1) know that the hypothesis can be falsified and (2) not to know if the hypothesis can be falsified. The example he has chosen reflects the fundamental idea of legitimizing falsifiable hypotheses. Soros defends this methodological stance the following way:
The three words "allows unverifiable hypotheses" with the word "unverifiable" in between shows the stance clearly. He also states that:
The possibility of the falsification of the hypothesis is shown also in the following:
This part of Soros' explanation deals not only with events but also the so-called full-blown Rational Expectations. To the last of these sentences he has attached a footnote with a sentence:
This raises of course the question what are "reflexive events". Here, it has been mentioned that it deals with the full-blown Rational Expectations. He continues:
The last sentence shows that Soros differentiates between natural and social sciences, and puts "a situation" under the social sciences. Thus there is a hidden class of unevents and unsituations, which are placed under the natural sciences. The sentence with "thinking participants" is the opposite of unconscious. This shows that the Popperian Open Society is constructed on a basis that can be eliminated. It also shows that Soros sees the hypothesis as connected to a historical phase, as the word "provisionally" shows. The sentence "But reflexivity gives rise to irreversible, historical processes" is striking, since it shows that reflexive events, based on the hypothesis that can be falsified, causes "irreversible, historical processes". Soros describes that these are fruitful misconceptions.
George Soros' description shows that Karl Popper's idea about the validity of the hypothesis is essentially the same which is described by Milton Friedman in Essays in Positive Economics. Soros' and Friedman's claims are game-theoretic. Thorstein Veblen has written about these what became known as game-theoretic operations in his 1919 essay The Intellectual Pre-Eminence of Jews in Modern Europe.:
The second last sentence with "scientific theory, even beyond the extent of its application in the workday detail" refers exactly to the fundamental question what is scientific and what is not. The question which Soros and f.e. Popper and Friedman before him have equipped with claims. Soros (p. 90) suggests:
The words "equally exhilarating" refer to the preceding page (p. 89):
There first of these citations here (and vice verse in the book) has "we may be able to avoid some of the excesses of the dawning of the new age" and the second has "No wonder that the new approach was carried to excess!". It should be noted that the first of these has the word "may", referring to the full-blown Rational Expectations like the "Age of Fallibility" declaration. Notice also the words "Greek philosophy" and the usage of the relatively rare word "couched". Alisa Rosenbaum's a.k.a Ayn Rand's book Atlas Shrugged has a following scene:
Soros continues (p. 90):
So there is the universality claim that is included in Ayn Rand's most famous work, in the sentence "'for these truths hold good for everything that is, and not for some special genus apart from others'", and his words "common ground" carries the idea included in Rand's citation with "'such a principle is the most certain of all'".
According to Soros (p. 90):
According to Soros (p. 90):
The metacognitive mind's expectations differ from the non-metacognitive, which is discussed shortly above. Since Rational Expectations method can be applied to different economic models, the emphasis is on the interest of the actors. Alan A. Walters has described this clearly but at the same time connects it to the quantity theory in his (1971) article Consistent Expectations, Distributed Lags and the Quantity Theory. The applicability to different models leads to the possibility of an alternative Age of Fallibility as well, but it is constrained by the difference in the resources of the actors. The application of quantity theory in monetary policy is a prime example of and inseparable from the workings of the metacognitive interest-based actors. It should be noted that the Phillips curve debate in which John Hicks was involved, was essentially an internal debate of the New Classical Economics, which affected to its outcome. One of the key moments was Milton Friedman's (1976) Nobel memorial prize lecture Inflation and Unemployment including f.e. this short sentence (p. 270):
The speech (p. 267) contains also Friedman's definition of hypothesis validation which corresponds Popper's (and Soros') claim:
This shows that maintaining this kind of hypotheses have, in order to escape the rejection, the tendency to lead to attacks on the alternative models, theories and hypotheses. The essential basis of what George Soros (1998) calls "market fundamentalism" has its very basis in the Popperian process of validation, both he and Milton Friedman are keen supporters of. This shows also that this kind of hypotheses have more or less transitory existence, and lead the powerholders to construct alternative bases of power.
Vandalism in deleting material from the article
The material deleted is now recovered. The deletion was vandalism. If the knowledge and references do not please you there should also be an argument that is valid. Is this again a trial to escape the possible rejection?
- "When Milton received his Medal of Freedom in 1988, President George H. W. Bush said jokingly in his speech that Rose was known for being the only person to ever have won an argument against her husband." (Wikipedia EN Rose Friedman)Dancing Mickey Mouse (talk) 21:01, 5 October 2016 (UTC)
- Evans, G. W. and G. Ramey (2006) Adaptive Expectations, Underparameterization and the Lucas Critique. Journal of Monetary Economics, vol. 53, pp. 249-264.
- Allais, M. (1965), Reformulation de la théorie quantitative de la monnaie, Société d’études et de documentation économiques, industrielles et sociales (SEDEIS), Paris.
- Friedman, M. (1968), Factors affecting the level of interest rates, in Savings and residential financing: 1968 Conference Proceedings, Jacobs, D. P., and Pratt, R. T., (eds.), The United States Saving and Loan League, Chicago, IL, p. 375.
- Barthalon, E. (2014), Uncertainty, Expectations and Financial Instability, Reviving Allais’s Lost Theory of Psychological Time, Columbia University Press, New York.
- Soros, George (1998): The Crisis of Global Capitalism: Open Society endangered. Little, Brown and Company.
- Veblen, Thorstein (1919): The Intellectual Pre-Eminence of Jews in Modern Europe. Political Science Quarterly. Vol.34, No.1 (March 1919) pp. 33-42
- Soros, George (1998): The Crisis of Global Capitalism: Open Society endangered. Little, Brown and Company.
- Rand, Ayn: Atlas Shrugged. Penguin Books. pp. 1167-1168