Why game theory will be nothing but a footnote in the history of social science

30 September, 2017 at 12:35 | Posted in Economics | Comments Off on Why game theory will be nothing but a footnote in the history of social science

Nash equilibrium has since it was introduced back in the 50’s come to be the standard solution concept used by game theorists. The justification for its use has mainly built on dubious and contentious assumptions like ‘common knowledge’ and individuals exclusively identified as instrumentally rational. And as if that wasn’t enough, one actually, to ‘save’ the Holy Equilibrium Grail, has had to further make the ridiculously unreal assumption that those individuals have ‘consistently aligned beliefs’ — effectively treating different individuals as incarnations of the microfoundationalist ‘representative agent.’

In the beginning — in the 50’s and 60’s — hopes were high that game theory would enhance our possibilities of understanding/explaining the behaviour of interacting actors in non-parametric settings. And this is where we ended up! A sad story, indeed, showing the limits of methodological individualism and instrumental rationality.

Why not give up on the Nash concept altogether? Why not give up the vain dream of trying to understand social interaction by reducing it to something that can be analyzed within a grotesquely unreal model of instrumentally interacting identical robot imitations?

We believe that a variety of contributory factors can be identified …

gaIt is possible that the strange philosophical moorings of neoclassical economics and game theory have played a part. They are strange in at least two respects. The first is a kind of amnesia or lobotomy which the discipline seems to have suffered regarding most things philosophical during the postwar period … The second is the utilitarian historical roots of modern economics … Thirdly, the sociology of the discipline may provide further clues … All academics have fought their corner in battles over resources and they always use the special qualities of their discipline as ammunition in one way or another. Thus one might explain in functionalist terms the mystifying attachments of economics and game theory to Nash.

Half a century ago there was​ widespread hopes game theory would provide a unified theory of all social science. Today it has become obvious those hopes did not materialize. This ought to come as no surprise. Reductionist and atomistic models of social interaction — such as the ones neoclassical mainstream economics is founded on — can never deliver good building blocks for a realist and relevant social science.

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Rational expectations — the triumph of ideology over science

29 September, 2017 at 18:53 | Posted in Economics | 2 Comments

Research shows not only that individuals sometimes act differently than standard economic theories predict, but that they do so regularly, systematically, and in ways that can be understood and interpreted through alternative hypotheses, competing with those utilised by orthodox economists.

Senate Banking Subcommittee On Financial Institutions Hearing With StiglitzTo most market participants — and, indeed, ordinary observers — this does not seem like big news … In fact, this irrationality is no news to the economics profession either. John Maynard Keynes long ago described the stock market as based not on rational individuals struggling to uncover market fundamentals, but as a beauty contest in which the winner is the one who guesses best what the judges will say …

Adam Smith’s invisible hand — the idea that free markets lead to efficiency as if guided by unseen forces — is invisible, at least in part, because it is not there …

For more than 20 years, economists were enthralled by so-called “rational expectations” models which assumed that all participants have the same (if not perfect) information and act perfectly rationally, that markets are perfectly efficient, that unemployment never exists (except when caused by greedy unions or government minimum wages), and where there is never any credit rationing.

That such models prevailed, especially in America’s graduate schools, despite evidence to the contrary, bears testimony to a triumph of ideology over science. Unfortunately, students of these graduate programmes now act as policymakers in many countries, and are trying to implement programmes based on the ideas that have come to be called market fundamentalism … Good science recognises its limitations, but the prophets of rational expectations have usually shown no such modesty.

Joseph Stiglitz

 
Those who want to build macroeconomics on microfoundations usually maintain that the only robust policies and institutions are those based on rational expectations and representative actors. As yours truly has tried to show in On the use and misuse of theories and models in economics there is really no support for this conviction at all. On the contrary. If we want to have anything of interest to say on real economies, financial crisis and the decisions and choices real people make, it is high time to place macroeconomic models building on representative actors and rational expectations microfoundations in the dustbin of pseudo-science.

For if this microfounded macroeconomics has nothing to say about the real world and the economic problems out there, why should we care about it? The final court of appeal for macroeconomic models is the real world, and as long as no convincing justification is put forward for how the inferential bridging de facto is made, macroeconomic modelbuilding is little more than hand-waving that give us a rather little warrant for making inductive inferences from models to real world target systems. If substantive questions about the real world are being posed, it is the formalistic-mathematical representations utilized to analyze them that have to match reality, not the other way around.

The real macroeconomic challenge is to accept uncertainty and still try to explain why economic transactions take place — instead of simply conjuring the problem away by assuming rational expectations and treating uncertainty as if it was possible to reduce it to stochastic risk. That is scientific cheating. And it has been going on for too long now.

In Dreams

29 September, 2017 at 16:15 | Posted in Varia | 1 Comment


In loving memory of Kristina — beloved wife and mother of David and Tora.

Like Tears in Rain

29 September, 2017 at 15:34 | Posted in Varia | Comments Off on Like Tears in Rain

 

Hicks on neoclassical ‘uncertainty laundering’

28 September, 2017 at 09:56 | Posted in Economics | Comments Off on Hicks on neoclassical ‘uncertainty laundering’

To understand real world ‘non-routine’ decisions and unforeseeable changes in behaviour, ergodic probability distributions are of no avail. In a world full of genuine uncertainty — where real historical time rules the roost — the probabilities that ruled the past are not necessarily those that will rule the future.

Wickham, Mark, active 1984-2000; Sir John Hicks (1904-1989)When we cannot accept that the observations, along the time-series available to us, are independent … we have, in strict logic, no more than one observation, all of the separate items having to be taken together. For the analysis of that the probability calculus is useless; it does not apply … I am bold enough to conclude, from these considerations that the usefulness of ‘statistical’ or ‘stochastic’ methods in economics is a good deal less than is now conventionally supposed … We should always ask ourselves, before we apply them, whether they are appropriate to the problem in hand. Very often they are not … The probability calculus is no excuse for forgetfulness.

John Hicks, Causality in Economics, 1979:121

Time to abandon statistical significance

27 September, 2017 at 10:55 | Posted in Statistics & Econometrics | 6 Comments

worship-p-300x214We recommend dropping the NHST [null hypothesis significance testing] paradigm — and the p-value thresholds associated with it — as the default statistical paradigm for research, publication, and discovery in the biomedical and social sciences. Specifically, rather than allowing statistical signicance as determined by p < 0.05 (or some other statistical threshold) to serve as a lexicographic decision rule in scientic publication and statistical decision making more broadly as per the status quo, we propose that the p-value be demoted from its threshold screening role and instead, treated continuously, be considered along with the neglected factors [such factors as prior and related evidence, plausibility of mechanism, study design and data quality, real world costs and benefits, novelty of finding, and other factors that vary by research domain] as just one among many pieces of evidence.

We make this recommendation for three broad reasons. First, in the biomedical and social sciences, the sharp point null hypothesis of zero effect and zero systematic error used in the overwhelming majority of applications is generally not of interest because it is generally implausible. Second, the standard use of NHST — to take the rejection of this straw man sharp point null hypothesis as positive or even definitive evidence in favor of some preferredalternative hypothesis — is a logical fallacy that routinely results in erroneous scientic reasoning even by experienced scientists and statisticians. Third, p-value and other statistical thresholds encourage researchers to study and report single comparisons rather than focusing on the totality of their data and results.

Andrew Gelman et al.

ad11As shown over and over again when significance tests are applied, people have a tendency to read ‘not disconfirmed’ as ‘probably confirmed.’ Standard scientific methodology tells us that when there is only say a 10 % probability that pure sampling error could account for the observed difference between the data and the null hypothesis, it would be more ‘reasonable’ to conclude that we have a case of disconfirmation. Especially if we perform many independent tests of our hypothesis and they all give about the same 10 % result as our reported one, I guess most researchers would count the hypothesis as even more disconfirmed.

We should never forget that the underlying parameters we use when performing significance tests are model constructions. Our p-values mean nothing if the model is wrong. And most importantly — statistical significance tests DO NOT validate models!

statistical-models-sdl609573791-1-42fd0In journal articles a typical regression equation will have an intercept and several explanatory variables. The regression output will usually include an F-test, with p – 1 degrees of freedom in the numerator and n – p in the denominator. The null hypothesis will not be stated. The missing null hypothesis is that all the coefficients vanish, except the intercept.

If F is significant, that is often thought to validate the model. Mistake. The F-test takes the model as given. Significance only means this: if the model is right and the coefficients are 0, it is very unlikely to get such a big F-statistic. Logically, there are three possibilities on the table:
i) An unlikely event occurred.
ii) Or the model is right and some of the coefficients differ from 0.
iii) Or the model is wrong.
So?

Neoliberal ‘ethics’

26 September, 2017 at 13:20 | Posted in Politics & Society | 3 Comments

As we all know, neoliberalism is nothing but a self-serving con endorsing pernicious moral cynicism. But it’s still sickening to read its gobsmacking trash, maintaining that unregulated capitalism is a ‘superlatively moral system’:

neo The rich man may feast on caviar and champagne, while the poor woman starves at his gate. And she may not even take the crumbs from his table, if that would deprive him of his pleasure in feeding them to his birds.
 

David Gauthier Morals by Agreement

Now, compare that unashamed neoliberal apologetics with what two truly great economists and liberals — John Maynard Keynes and Robert Solow — have to say:

The outstanding faults of the economic society in which we live are its failure to provide for full employment and its arbitrary and inequitable distribution of wealth and incomes … I believe that there is social and psychological justification for significant inequalities of income and wealth, but not for such large disparities as exist to-day.

John Maynard Keynes General Theory (1936)

4703325Who could be against allowing people their ‘just deserts?’ But there is that matter of what is ‘just.’ Most serious ethical thinkers distinguish between deservingness and happenstance. Deservingness has to be rigorously earned. You do not ‘deserve’ that part of your income that comes from your parents’ wealth or connections or, for that matter, their DNA. You may be born just plain gorgeous or smart or tall, and those characteristics add to the market value of your marginal product, but not to your deserts. It may be impractical to separate effort from happenstance numerically, but that is no reason to confound them, especially when you are thinking about taxation and redistribution. That is why we want to temper the wind to the shorn lamb, and let it blow on the sable coat.

Robert Solow Journal of Economic Perspectives (2014)

Public debt — an economic necessity

26 September, 2017 at 09:06 | Posted in Economics | 6 Comments

wvickreyWe are not going to get out of the economic doldrums as long as we continue to be obsessed with the unreasoned ideological goal of reducing the so-called deficit. The “deficit” is not an economic sin but an economic necessity. […]

The administration is trying to bring the Titanic into harbor with a canoe paddle, while Congress is arguing over whether to use an oar or a paddle, and the Perot’s and budget balancers seem eager to lash the helm hard-a-starboard towards the iceberg. Some of the argument seems to be over which foot is the better one to shoot ourselves in. We have the resources in terms of idle manpower and idle plants to do so much, while the preachers of austerity, most of whom are in little danger of themselves suffering any serious consequences, keep telling us to tighten our belts and refrain from using the resources that lay idle all around us.

Alexander Hamilton once wrote “A national debt, if it be not excessive, would be for us a national treasure.” William Jennings Bryan used to declaim, “You shall not crucify mankind upon a cross of gold.” Today’s cross is not made of gold, but is concocted of a web of obfuscatory financial rectitude from which human values have been expunged.

William Vickrey

Right-wing extremist party in German parliament for the first time since WWII

25 September, 2017 at 13:57 | Posted in Politics & Society | Comments Off on Right-wing extremist party in German parliament for the first time since WWII

 

Trump’s ‘alternative facts’ exported to German politics …

Seven sins of economics

23 September, 2017 at 11:44 | Posted in Economics | 4 Comments

There has always been some level of scepticism about the ability of economists to offer meaningful predictions and prognosis about economic and social phenomenon. That scepticism has heightened in the wake of the global financial crisis, leading to what is arguably the biggest credibility crisis the discipline has faced in the modern era.

assumpSome of the criticisms against economists are misdirected. But the major thrust of the criticisms does have bite.

There are seven key failings, or the ‘seven sins’, as I am going to call them, that have led economists to their current predicament. These include sins of commission as well as sins of omission.

Sin 1: Alice in Wonderland assumptions

The problem with economists is not that they make assumptions. After all, any theory or model will have to rely on simplifying assumptions … But when critical assumptions are made just to circumvent well-identified complexities in the quest to build elegant theories, such theories will simply end up being elegant fantasies.

Sin 2: Abuse of modelling

What compounds the sin of wild assumptions is the sin of careless modelling, and then selling that model as if it were a true depiction of an economy or society …

Sin 3: Intellectual capture

Several post-crisis assessments of the economy and of economics have pointed to intellectual capture as a key reason the profession, as a whole failed, to sound alarm bells about problems in the global economy, and failed to highlight flaws in the modern economic architecture …

Sin 4: The science obsession

The excessive obsession in the discipline to identify itself as science has been costly. This has led to a dangerous quest for standardization in the profession, leading many economists to mistake a model of the economy for ‘the model’ of the economy …

The science obsession has diminished the diversity of the profession, and arguably allowed complacency to take root in the run-up to the global financial crisis …

Sin 5: Perpetuating the myth of ‘the textbook’ and Econ 101

The quest for standardization has also led to an astonishing level of uniformity in the manner in which economists are trained, and in the manner in which economists train others. Central to this exercise are textbooks that help teach the lessons of ‘Econ 101’—lessons disconnected from reality as they are from the frontiers of economic research …

Sin 6: Ignoring society

What makes Econ 101 and a lot of mainstream economics particularly limiting is its neglect of the role of culture and social norms in determining economic outcomes even though classical economists such as Adam Smith and Karl Marx took care to emphasize how social norms and social interactions shape economic outcomes …

Economists typically don’t engage with other social sciences, even though insights from those disciplines have a direct bearing on the subjects of economic enquiry …

Sin 7: Ignoring history

One way in which economists could have compensated for the lack of engagement with other social sciences is by studying economic history. After all, studying economic history carefully can help us understand the social and institutional contexts in which particular economic models worked, or did not work …

But economic history has been relegated to the margins over the past several years, and many graduate students remain unacquainted with the subject still.

Pramit Bhattacharya

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