The role of RCTs in development

15 Jul, 2021 at 14:25 | Posted in Statistics & Econometrics | Leave a comment

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Econometrics — science based on unwarranted assumptions

15 Jul, 2021 at 11:52 | Posted in Statistics & Econometrics | 1 Comment

Machine Learning or Econometrics? | by Dr. Dataman | Analytics Vidhya |  MediumThere is first of all the central question of methodology — the logic of applying the method of multiple correlation to unanalysed economic material, which we know to be non-homogeneous through time. If we are dealing with the action of numerically measurable, independent forces, adequately analysed so that we were dealing with independent atomic factors and between them completely comprehensive, acting with fluctuating relative strength on material constant and homogeneous through time, we might be able to use the method of multiple correlation with some confidence for disentangling the laws of their action … In fact we know that every one of these conditions is far from being satisfied by the economic material under investigation.

Letter from John Maynard Keynes to Royall Tyler (1938)

Mainstream economists often hold the view that criticisms of econometrics are the conclusions of sadly misinformed and misguided people who dislike and do not understand much of it. This is a gross misapprehension. To be careful and cautious is not equivalent to dislike.

Keynes' critique of econometrics — as valid today as it was in 1939 | LARS  P. SYLL

The ordinary deductivist ‘textbook approach’ to econometrics views the modelling process as foremost an estimation problem since one (at least implicitly) assumes that the model provided by economic theory is a well-specified and ‘true’ model. The more empiricist, general-to-specific-methodology (often identified as the ‘LSE approach’) on the other hand views models as theoretically and empirically adequate representations (approximations) of a data generating process (DGP). Diagnostics tests (mostly some variant of the F-test) are used to ensure that the models are ‘true’ – or at least ‘congruent’ – representations of the DGP. The modelling process is here more seen as a specification problem where poor diagnostics results may indicate a possible misspecification requiring re-specification of the model. The objective is standardly to identify models that are structurally stable and valid across a large time-space horizon. The DGP is not seen as something we already know, but rather something we discover in the process of modelling it. Considerable effort is put into testing to what extent the models are structurally stable and generalizable over space and time.

Although yours truly has some sympathy for this approach in general, there are still some unsolved ‘problematics’ with its epistemological and ontological presuppositions. There is, e. g., an implicit assumption that the DGP fundamentally has an invariant property and that models that are structurally unstable just have not been able to get hold of that invariance. But one cannot just presuppose or take for granted that kind of invariance. It has to be argued and justified. Grounds have to be given for viewing reality as satisfying conditions of model-closure. It is as if the lack of closure that shows up in the form of structurally unstable models somehow could be solved by searching for more autonomous and invariable ‘atomic uniformity.’ But if reality is ‘congruent’ to this analytical prerequisite has to be argued for, and not simply taken for granted.

A great many models are compatible with what we know in economics — that is to say, do not violate any matters on which economists are agreed. Attractive as this view is, it fails to draw a necessary distinction between what is assumed and what is merely proposed as hypothesis. This distinction is forced upon us by an obvious but neglected fact of statistical theory: the matters ‘assumed’ are put wholly beyond test, and the entire edifice of conclusions (e.g., about identifiability, optimum properties of the estimates, their sampling distributions, etc.) depends absolutely on the validity of these assumptions. The great merit of modern statistical inference is that it makes exact and efficient use of what we know about reality to forge new tools of discovery, but it teaches us painfully little about the efficacy of these tools when their basis of assumptions is not satisfied. 

Millard Hastay

Even granted that closures come in degrees, we should not compromise on ontology. Some methods simply introduce improper closures, closures that make the disjuncture between models and real-world target systems inappropriately large. ‘Garbage in, garbage out.’

Underlying the search for these immutable ‘fundamentals’ is the implicit view of the world as consisting of entities with their own separate and invariable effects. These entities are thought of as being able to be treated as separate and addible causes, thereby making it possible to infer complex interaction from a knowledge of individual constituents with limited independent variety. But, again, if this is a justified analytical procedure cannot be answered without confronting it with the nature of the objects the models are supposed to describe, explain or predict. Keynes thought it generally inappropriate to apply the ‘atomic hypothesis’ to such an open and ‘organic entity’ as the real world. As far as I can see these are still appropriate strictures all econometric approaches have to face. Grounds for believing otherwise have to be provided by the econometricians.

Trygve Haavelmo, the father of modern probabilistic econometrics, wrote (in ‘Statistical testing of business-cycle theories’, The Review of  Economics and Statistics, 1943) that he and other econometricians could not build a complete bridge between our models and reality by logical operations alone, but finally had to make “a non-logical jump” [1943:15]. A part of that jump consisted in that econometricians “like to believe … that the various a priori possible sequences would somehow cluster around some typical time shapes, which if we knew them, could be used for prediction” [1943:16]. But since we do not know the true distribution, one has to look for the mechanisms (processes) that “might rule the data” and that hopefully persist so that predictions may be made. Of possible hypotheses on different time sequences (“samples” in Haavelmo’s somewhat idiosyncratic vocabulary) most had to be ruled out a priori “by economic theory”, although “one shall always remain in doubt as to the possibility of some … outside hypothesis being the true one” [1943:18].

Continue Reading Econometrics — science based on unwarranted assumptions…

Die Impfentscheidung als rein individuelle Entscheidung

14 Jul, 2021 at 16:12 | Posted in Politics & Society | Leave a comment

Gestern — in der ZDF-Talkshow “Markus Lanz” — bekannte Sarah Wagenknecht das Sie habe “Bedenken” und sich vorerst gegen eine Corona-Impfung entschieden. Ich finde diese Einstellung sehr enttäuschend. Impfen oder nicht impfen ist nicht nur eine Frage für Einzelpersonen, da Ihre Impfung auch andere schützt, Frau Wagenknecht!

Postmodernism — an anti-intellectual abyss

14 Jul, 2021 at 09:08 | Posted in Politics & Society | Leave a comment

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Critical race theory debunked

13 Jul, 2021 at 14:08 | Posted in Politics & Society | 1 Comment

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Color Martin Luther King Jr Quotes I Have A Dream - New Quotes

La France en crise

13 Jul, 2021 at 12:14 | Posted in Economics | 1 Comment

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Critical race theory — a guide

12 Jul, 2021 at 11:20 | Posted in Politics & Society | 3 Comments

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Über linke und rechte Identitätspolitik

12 Jul, 2021 at 10:49 | Posted in Politics & Society | 2 Comments

Wie links ist es etwa, wenn jüdische Studenten der Universität von Virginia von einer Initiative gegen weisse Suprematisten ausgeschlossen werden, weil sie aus Sicht ihrer gojischen, progressiven Kommilitonen und eifrigen Identitätskommissare als Juden bestimmt Israel unterstützen und damit dieselben Rassisten sind wie alle Israelis? … …

Identity_politicsEs gibt, glaube ich, noch eine weitere schreckliche Gemeinsamkeit zwischen linker und rechter Identitätspolitik … So wie die alten 20.-Jahrhundert-Nazis in ihrer Jugend ein Haufen zu kurz gekommener, neidischer, völlig unbegabter, asozialer deutscher Kleinstspießer und Lumpenproletarier waren, die sich in der bürgerlichen und ziemlich jüdischen Leistungsgesellschaft des ausgehenden 19. Jahrhunderts nicht zurechtfanden und sich, statt selbst gute Schriftsteller, Börsenmakler oder Ärzte zu werden, kurzerhand zu privilegierten Quoten-Deutschen, auch bekannt als Herrenmenschen erklärten, was die Deutschen an sich, als ewiges Zukurzgekommenenvolk, eh super fanden – genauso kommen mir heute viele, wirklich sehr viele Identitäts-Politik-People vor, die mit dem tränenreichen, stigmatisierenden Hinweis auf die sie angeblich beleidigende sexuelle, soziale, geschlechtliche, moralische Zugehörigkeit von Irgendwem zu Irgendwas einfach nur gesellschaftliche und berufliche Konkurrenten aus dem Weg räumen wollen, um zum Schluss selbst ihren Platz einzunehmen.

Maxim Biller / Die Zeit

Maxim Biller ist mal wieder gereizt. Eine Provokation? Ja. Aber auch ernüchternde!

Ontological emergence

10 Jul, 2021 at 10:37 | Posted in Theory of Science & Methodology | 4 Comments

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The Frankfurt School — from a failed revolution to critical theory

9 Jul, 2021 at 10:17 | Posted in Politics & Society | 3 Comments

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Causal inference in social sciences (student stuff)

8 Jul, 2021 at 11:32 | Posted in Statistics & Econometrics | Leave a comment

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Deductivism — the original sin in mainstream economics

7 Jul, 2021 at 16:25 | Posted in Economics | 4 Comments

Mathematics, especially through the work of David Hilbert, became increasingly conceived as a practice concerned with formulating systems comprising sets of axioms and their deductive consequences, with these systems in effect taking on a life of their own …

Confusion of sign and object is original sin coeval with the word.The emergence of the axiomatic method removed at a stroke various hitherto insurmountable constraints facing those who would mathematise the discipline of economics … In particular it was no longer regarded as necessary, or even relevant, to economic model construction to consider the nature of social reality …

The result was that in due course deductivism in economics, through morphing into mathematical deductivism on the back of developments within the discipline of mathematics, came to acquire a new lease of life, with practitioners (once more) potentially oblivious to any inconsistency between the ontological presuppositions of adopting a mathematical modelling emphasis and the nature of social reality.

Tony Lawson

To be ‘analytical’ and ‘logical’ is something most people find recommendable. These words have a positive connotation. Scientists think deeper than most other people because they use ‘logical’ and ‘analytical’ methods. In dictionaries, logic is often defined as “reasoning conducted or assessed according to strict principles of validity” and ‘analysis’ as having to do with “breaking something down.”

anBut that’s not the whole picture. As used in science, analysis usually means something more specific. It means to separate a problem into its constituent elements so to reduce complex — and often complicated — wholes into smaller (simpler) and more manageable parts. You take the whole and break it down (decompose) into its separate parts. Looking at the parts separately one at a time you are supposed to gain a better understanding of how these parts operate and work. Built on that more or less ‘atomistic’ knowledge you are then supposed to be able to predict and explain the behaviour of the complex and complicated whole.

In economics, that means you take the economic system and divide it into its separate parts, analyse these parts one at a time, and then after analysing the parts separately, you put the pieces together.

The ‘analytical’ approach is typically used in economic modelling, where you start with a simple model with few isolated and idealized variables. By ‘successive approximations,’ you then add more and more variables and finally get a ‘true’ model of the whole.

This may sound like a convincing and good scientific approach.

But there is a snag!

The procedure only really works when you have a machine-like whole/system/economy where the parts appear in fixed and stable configurations. And if there is anything we know about reality, it is that it is not a machine! The world we live in is not a ‘closed’ system. On the contrary. It is an essentially ‘open’ system. Things are uncertain, relational, interdependent, complex, and ever-changing.

Without assuming that the underlying structure of the economy that you try to analyze remains stable/invariant/constant, there is no chance the equations of the model remain constant. That’s the very rationale why economists use (often only implicitly) the assumption of ceteris paribus. But — nota bene — this can only be a hypothesis. You have to argue the case. If you cannot supply any sustainable justifications or warrants for the adequacy of making that assumption, then the whole analytical economic project becomes pointless non-informative nonsense. Not only have we to assume that we can shield off variables from each other analytically (external closure). We also have to assume that each and every variable themselves are amenable to be understood as stable and regularity producing machines (internal closure). Which, of course, we know is as a rule not possible. Some things, relations, and structures are not analytically graspable. Trying to analyse parenthood, marriage, employment, etc, piece by piece doesn’t make sense. To be a chieftain, a capital-owner, or a slave is not an individual property of an individual. It can come about only when individuals are integral parts of certain social structures and positions. Social relations and contexts cannot be reduced to individual phenomena. A cheque presupposes a banking system and being a tribe-member presupposes a tribe.  Not taking account of this in their ‘analytical’ approach, economic ‘analysis’ becomes uninformative nonsense.

Using ‘logical’ and ‘analytical’ methods in social sciences means that economists succumb to the fallacy of composition — the belief that the whole is nothing but the sum of its parts.  In society and in the economy this is arguably not the case. An adequate analysis of society and economy a fortiori cannot proceed by just adding up the acts and decisions of individuals. The whole is more than a sum of parts.

Mainstream economics is built on using the ‘analytical’ method. The models built with this method presuppose that social reality is ‘closed.’ Since social reality is known to be fundamentally ‘open,’ it is difficult to see how models of that kind can explain anything about what happens in such a universe. Postulating closed conditions to make models operational and then impute these closed conditions to society’s real structure is an unwarranted procedure that does not take necessary ontological considerations seriously.

In face of the kind of methodological individualism and rational choice theory that dominate mainstream economics we have to admit that even if knowing the aspirations and intentions of individuals are necessary prerequisites for giving explanations of social events, they are far from sufficient. Even the most elementary ‘rational’ actions in society presuppose the existence of social forms that it is not possible to reduce to the intentions of individuals. Here, the ‘analytical’ method fails again.

The overarching flaw with the ‘analytical’ economic approach using methodological individualism and rational choice theory is basically that they reduce social explanations to purportedly individual characteristics. But many of the characteristics and actions of the individual originate in and are made possible only through society and its relations. Society is not a Wittgensteinian ‘Tractatus-world’ characterized by atomistic states of affairs. Society is not reducible to individuals, since the social characteristics, forces, and actions of the individual are determined by pre-existing social structures and positions. Even though society is not a volitional individual, and the individual is not an entity given outside of society, the individual (actor) and the society (structure) have to be kept analytically distinct. They are tied together through the individual’s reproduction and transformation of already given social structures.

Since at least the marginal revolution in economics in the 1870s it has been an essential feature of economics to ‘analytically’ treat individuals as essentially independent and separate entities of action and decision. But, really, in such a complex, organic and evolutionary system as an economy, that kind of independence is a deeply unrealistic assumption to make. To simply assume that there is strict independence between the variables we try to analyze doesn’t help us the least if that hypothesis turns out to be unwarranted.

To be able to apply the ‘analytical’ approach, economists have to basically assume that the universe consists of ‘atoms’ that exercise their own separate and invariable effects in such a way that the whole consist of nothing but an addition of these separate atoms and their changes. These simplistic assumptions of isolation, atomicity, and additivity are, however, at odds with reality. In real-world settings, we know that the ever-changing contexts make it futile to search for knowledge by making such reductionist assumptions. Real-world individuals are not reducible to contentless atoms and so not susceptible to atomistic analysis. The world is not reducible to a set of atomistic ‘individuals’ and ‘states.’ How variable X works and influence real-world economies in situation A cannot simply be assumed to be understood or explained by looking at how X works in situation B. Knowledge of X probably does not tell us much if we do not take into consideration how it depends on Y and Z. It can never be legitimate just to assume that the world is ‘atomistic.’ Assuming real-world additivity cannot be the right thing to do if the things we have around us rather than being ‘atoms’ are ‘organic’ entities.

If we want to develop new and better economics we have to give up on the single-minded insistence on using a deductivist straitjacket methodology and the ‘analytical’ method. To focus scientific endeavours on proving things in models is a gross misapprehension of the purpose of economic theory. Deductivist models and ‘analytical’ methods disconnected from reality are not relevant to predict, explain or understand real-world economies

To have ‘consistent’ models and ‘valid’ evidence is not enough. What economics needs are real-world relevant models and sound evidence. Aiming only for ‘consistency’ and ‘validity’ is setting the economics aspirations level too low for developing a realist and relevant science.

Economics is not mathematics or logic. It’s about society. The real world.

Models may help us think through problems. But we should never forget that the formalism we use in our models is not self-evidently transportable to a largely unknown and uncertain reality. The tragedy with mainstream economic theory is that it thinks that the logic and mathematics used are sufficient for dealing with our real-world problems. They are not! Model deductions based on questionable assumptions can never be anything but pure exercises in hypothetical reasoning.

The world in which we live is inherently uncertain and quantifiable probabilities are the exception rather than the rule. To every statement about it is attached a ‘weight of argument’ that makes it impossible to reduce our beliefs and expectations to a one-dimensional stochastic probability distribution. If “God does not play dice” as Einstein maintained, I would add “nor do people.” The world as we know it has limited scope for certainty and perfect knowledge. Its intrinsic and almost unlimited complexity and the interrelatedness of its organic parts prevent the possibility of treating it as constituted by ‘legal atoms’ with discretely distinct, separable and stable causal relations. Our knowledge accordingly has to be of a rather fallible kind.

If the real world is fuzzy, vague and indeterminate, then why should our models build upon a desire to describe it as precise and predictable? Even if there always has to be a trade-off between theory-internal validity and external validity, we have to ask ourselves if our models are relevant.

‘Human logic’ has to supplant the classical — formal — logic of deductivism if we want to have anything of interest to say of the real world we inhabit. Logic is a marvellous tool in mathematics and axiomatic-deductivist systems, but a poor guide for action in real-world systems, in which concepts and entities are without clear boundaries and continually interact and overlap. In this world, I would say we are better served with a methodology that takes into account that the more we know, the more we know we do not know.

Mathematics and logic cannot establish the truth value of facts. Never has. Never will.

What we do in life echoes in eternity

7 Jul, 2021 at 12:11 | Posted in Varia | 2 Comments

In science, courage is to follow the motto of enlightenment and Kant’s dictum — Sapere Aude!  To use your own understanding, having the ​courage to think for yourself and question ‘received opinion’, authority or orthodoxy.

In our daily lives, courage is a capability to confront fear, as when in front of the powerful and mighty, not to step back, but stand up for one’s rights not to be humiliated or abused.

Courage is to do the right thing in spite of danger and fear.

As when Sir Nicholas Winton organised the rescue of 669 children destined for Nazi concentration camps during World War II.

As when Ernest Shackleton, in April 1916, aboard the small boat ‘James Caird’, spent 16 days crossing 1,300 km of ocean to reach South Georgia, then trekked across the island to a whaling station, and finally could rescue the remaining men from the crew of ‘Endurance’ left on the Elephant Island. Not a single member of the expedition died.

As when Rosa Parks, on December 1, 1955, in Montgomery, Alabama, refused to give up her seat to make room for a white passenger.

As when Hans and Sophie Scholl — members of the resistance group ‘Die Weisse Rose’ — decided to fight the Nazi atrocities.

May their beautiful souls live on forever.

What we do in life echoes in eternity.

Debunking Jordan Peterson

6 Jul, 2021 at 15:58 | Posted in Politics & Society | Leave a comment

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The main ideas behind bootstrapping (student stuff)

6 Jul, 2021 at 10:50 | Posted in Statistics & Econometrics | Leave a comment

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