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Is A Fiscal Union Expensive For Its Rich Members?

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Josh Barro writing for The New York Times claims that a fiscal union for the Euro Area will be an enourmous expense for its rich members.

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He cites the example of Connecticut:

But the American fiscal union is very expensive for rich states. According to calculations by The Economist, Connecticut paid out 5 percent of its gross domestic product in net fiscal transfers to other states between 1990 and 2009; that is, its tax payments exceeded its receipt of government services by that amount. This is typical for rich states: They pay a disproportionate share of income and payroll taxes, while government services are disproportionately collected in states where people are poor or old or infirm.

This is blatantly wrong. It assumes that output of individual regions and the whole of the the Euro Area will roughly be the same with or without a fiscal union. It ignores the notion that each region may be better off because a supranational fiscal authority will have powers to raise output via expenditure and taxes which individual regions cannot achieve.

In his 1997 article Curried EMU — The Meal That Fails To Nourish for Observer, Wynne Godley made this point well (link):

A useful comparison can be made with the US. Americans often point that if would make no sense if each US state had its own currency, so what is all the fuss about? But the question should be asked the other way round. How would the US make out with no President, no Congress, no federal budget, and no federal institutions apart from the ‘Fed’ itself, plus a powerful central bureaucracy?

The analogy is useful because the United States does so obviously need a federal budget as well as a federal bank, and the activities of the two authorities have to be co-ordinated.  If there is a recession, remedial (expansionary) fiscal policy at the federal level is the only proper response; it is inconceivable that corrective action could be left to component states, which have neither the perspective nor the co-ordinating machinery to do the job. If there is a federal budget there must obviously be a legislative and executive apparatus that executes it and is democratically accountable for it. Moreover, the need for federal institutions extends far beyond economic affairs.

[emphasis added]

So it is incorrect to claim that a fiscal union is highly expensive for rich states. If there is a fiscal union, while rich regions will receive less from the supranational fiscal authority than what they pay in taxes, there’ll be higher output and income than otherwise simply because there is a powerful institution which raises output of each region. Rich nations will be able to net export more than otherwise, for example, compensating for transfers in absolute terms.

Analysis such as by Josh Barro are erroneous usually because of implicit assumptions made such as an aggregate production function, which implies a neutral role for fiscal policy. This can easily be verified: his assumption is that output is determined by other factors, not fiscal policy (because he doesn’t say so) and hence the role of a central government is one which just transfers from rich regions to poor, instead of having any impact on the output of the whole region. Silly.

Free Trade? Heterodox Dissent

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One of the most important message of this blog is that “free trade” is quite devastating to economies. In a recent article Economists Actually Agree on This: The Wisdom of Free Trade for The New York Times, Greg Mankiw once again pushes for free trade and also mentions that there is consensus in the profession.

Many of heterodox economists dissent on the issue of free trade. In this post, I will provide two examples: Joan Robinson and Wynne Godley.

Mankiw says:

Economists are famous for disagreeing with one another, and indeed, seminars in economics departments are known for their vociferous debate. But economists reach near unanimity on some topics, including international trade.

In the article, Mankiw tries to show among other things how free trade is the opposite of Mercantilism. Joan Robinson explained in her 1977 essay What Are The Questions? how foreign trade is important and that free trade is a subtle form of mercantilism.

According to Robinson:

A surplus of exports is advantageous, first of all, in connection with the short-period problem of effective demand. A surplus of value of exports over value of imports represents “foreign investment.” An increase in it has an employment and multiplier effect. Any increase in activity at home is liable to increase imports so that a boost to income and employment from an increase in the flow of home investment is partly offset by a reduction in foreign investment. A boost due to increasing exports or production of home substitutes for imports (when there is sufficient slack in the economy) does not reduce home investment, but creates conditions favorable to raising it. Thus, an export surplus is a more powerful stimulus to income than home investment.

In the beggar-my-neighbor scramble for trade during the great slump, every country was desparately trying to export its own unemployment. Every country had to join in, for any one that attempted to maintain employment without protecting its balance of trade (through tariffs, subsidies, depreciation, etc.) would have been beggared by the others.

From a long-run point of view, export-led growth is the basis of success. A country that has a competitive advantage in industrial production can maintain a high level of home investment, without fear of being checked by a balance-of-payments crisis. Capital accumulation and technical improvements then progressively enhance its competitive advantage. Employment is high and real-wage rates rising so that “labor trouble” is kept at bay. Its financial position is strong. If it prefers an extra rise of home consumption to acquiring foreign assets, it can allow its exchange rate to appreciate and turn the terms of trade in its own favor. In all these respects, a country in a weak competitive position suffers the corresponding disadvantages.

When Ricardo set out the case against protection, he was supporting British economic interests. Free trade ruined Portuguese industry. Free trade for others is in the interests of the strongest competitor in world markets, and a sufficiently strong competitor has no need for protection at home. Free trade doctrine, in practice, is a more subtle form of Mercantilism. When Britain was the workshop of the world, universal free trade suited her interests. When (with the aid of protection) rival industries developed in Germany and the United States, she was still able to preserve free trade for her own exports in the Empire. The historical tradition of attachment to free trade doctrine is so strong in England that even now, in her weakness, the idea of protectionism is considered shocking.

[emphasis: mine]

According to her colleague Wynne Godley, dissenting against free trade was one of the most important reasons for his dissent against the profession. In his short autobiography written in 2001 for A Biographical Dictionary Of Dissenting Economists (Edward Elgar book site), Godley says:

There are two aspects (in particular) of the work of the CEPG [Cambridge Economic Policy Group] which put its members into a category which may he termed ‘dissenting’. The first – a matter mainly of concern to the modelling fraternity and academic econometricians – was the unconventional view we took about how to construct and use an econometric model. Thus we attached prime importance to what may be termed ‘model architecture’ by which I mean that the underlying accounting was coherent, without any ‘dustbin’ equations or sectors; everything came from somewhere and went somewhere. Our view, by which I still stand, was that model architecture in this sense takes priority over parameter estimation; I am even prepared to conjecture that a properly a ‘architected’ model will deliver much the same results over a wide range of parameter estimates, particularly if the model is used for the simulation of medium- or long-term scenarios. Furthermore our use of the model was unconventional in that we treated it, not as something which would generate accurate forecasts of what would actually happen, but as a tool that informed our minds as to a great many possible outcomes conditional on a wide range of alternative assumptions both about exogenous variables and about parameter values. In using our model in this way we were greatly assisted by Cripps’s programming expertise, which permitted us to work with a speed and flexibility not generally available at that time. I should add that econometrics, as usually defined, played (advisedly) a relatively minor role in our work.

The second, and more egregious, respect in which we became a ‘dissident’ group was that, as a result of trying to think through the possible ways in which Britain’s net export demand might be improved, we entertained the possibility that international trade should be, in some sense, ‘managed’. There might, we argued, be no way in which the adverse trends could be reversed other than some form of control of imports. Our argument (see for instance Cripps, 1978; Cripps and Godley, 1978) was never one in favour of protectionism as normally understood – that is, the selective and unilateral protection of relatively failing industries under conditions of general stagnation. On the contrary, we were most careful to lay down conditions under which the management of trade would benefit not only our own country (without making its industry less efficient) but would also increase the level of trade and output in the rest of the world. The two basic principles were, first, that trade management should reduce import propensities without ever reducing imports themselves (in total) below what they otherwise would have been; and, second, that ‘protection’ should be as minimally selective as possible (for example, through the use of market mechanisms such as auction quotas) so that industrial inefficiency would not be sponsored.

I was surprised by the hostility with which our ideas about trade were received. It seemed to me at the time, and still seems to me, that the arguments actually used against us (at their most coherent by Maurice Scott et al., 1980) did not, in practice, rest on a well-articulated theoretical position but on very special assumptions about behavioural relationships and international political responses. (I have, to the best of my ability, answered these particular points in Christodoulakis and Godley, 1987.)

…

The ‘dissident’ argument in favour of managed trade is well summarized in Kaldor (1980), where he points out that the modern theory of international trade is based on the assumption that all production takes place according to the conditions described by the neoclassical production function, with constant returns to scale. Kaldor postulated instead, and he was surely right to do so, that the principle of circular and cumulative causation leads (through dynamically increasing returns) to a process, not of convergence, but of polarization between successful and unsuccessful economies in which success in competitive performance feeds on itself and losers become immiserated by trade.

The above quote is interesting from another perspective: it explains Godley’s views about modeling, policy, “forecasting” etc.

The Illogical Golden Rule

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There’s a nice article by Wynne Godley written in 2005 for The Guardian on the fiscal policy golden rule. There are two things wrong about the golden rule. The first is to think that capital expenditure is somehow superior to current expenditure. This is the reason one frequently hears “wonks” stressing on government infrastructure spending. The other is to ignore changes in private sector behaviour and foreign trade performance.

From the article:

Criticism of the fiscal policy regime has focused too much on whether Gordon Brown will break his self-imposed Golden Rule and not enough on whether the rule is acceptable. The Golden Rule states that the balance between receipts and current expenditure should be zero over the cycle, exempting public investment, which does not ‘count’ for the purpose of making this calculation.

A relatively minor objection to this arrangement is that there exists no relevant difference between, say, capital expenditure on school building and current expenditure on teachers. Both are equally necessary for education and both absorb resources (pound for pound) to roughly the same extent.

More fundamentally, the budget balance is equal to the difference between the government’s receipts and outlays, but it is also equal, by definition, to the sum of private net saving (personal and corporate combined) plus the balance of payments deficit.

If the private sector decides to save more, the government has no choice but to allow its budget deficit to rise unless it is prepared to sacrifice full employment; the same thing applies if uncorrected trends in foreign trade cause the balance of payments deficit to increase.

A sensible target for the budget balance cannot be set unless it is integrated into a view about what will happen to autonomous trends and propensities in private net saving and foreign trade. Moreover, as those trends and propensities change, it will never be possible to determine viable targets for the deficit that are fixed through time such as, for instance, that it should never exceed some number such as 3 per cent of GDP or that it should on average be zero.

Coming back to the medium-term future of the British economy: if, as seems quite possible, there is now a growth recession initiated by a fall in personal expenditure, the government will have no option but to allow the deficit to rise well beyond what the Golden Rule permits. The authorities will look ridiculous if they move the goalposts again, so the rule will have to be jettisoned. I don’t think it will be long before discretionary fiscal policy, once discredited by a few serious errors in the Sixties and Seventies, has to be rehabilitated.

Interest Rate, Growth And Debt Sustainability

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Frequently, discussions about debt sustainability have discussions about the importance of the interest rate and growth in debt sustainability analysis. See for example, today’s Paul Krugman’s post on his blog. It is concluded that as long as the rate of interest is below the rate of growth, the ratio public debt/gdp doesn’t explode. Unfortunately, this result is erroneous.

John Maynard Keynes’ biggest disservice to the profession is to not start with the open economy. In my view, debt sustainability is tightly connected to balance of payments.

Imagine a nation whose exports is constant. If output rises, it will have adverse effects on the current account balance of payments because of income induced increase in imports. This will have an adverse effect on the international investment position of the nation: the net international investment position will keep deteriorating unless output is slowed down or some measure is taken to improve exports. In the case of rising exports, there is a similar constraint, except it is weaker but dependent on the rate of growth of exports.

If the ratio net international investment position/gdp keeps deteriorating, either the public debt to non-residents or private indebtedness to non-residents or both have to keep rising, all unsustainable.

There are some complications. A nation’s balance of payments also depends on how assets held abroad and liabilities to foreigners affect the primary income account of balance of payments. Also, the exchange rate can depreciate (or be devalued in fixed-exchange rate regimes) improving exports and reducing imports. However assuming that exchange rate movements do the trick is believing in the invisible hand. Foreign trade doesn’t just depend on price competitiveness but also on non-price competitiveness. These complications are highly interesting but do not affect the fundamental fact that a nation’s success is dependent on the success of corporations to compete in international markets for goods in services.

Even the conclusion that the government should contract fiscal policy and aim for a primary surplus in its budget balance or else the ratio public debt/gdp keeps rising if the rate of interest is greater than the rate of growth is erroneous. Consider a closed economy. An expansion in fiscal policy will automatically raise output and gdp and hence tax collections to prevent the ratio public debt/gdp from exploding. The public sector balance may hit primary surpluses but not due to contraction of fiscal policy or targeting a primary surplus in its budget balance.

In short, although the rate of interest and the rate of growth are important in debt sustainability analysis, it is not as easy as is usually presenting in macroeconomics textbooks and in the blogosphere. For a more detailed analysis see the reference below.

Reference

  1. Godley, W. and B. Rowthorn (1994) ‘Appendix: The Dynamics of Public Sector Deficits and Debt.’ In J. Michie and J. Grieve Smith (eds.), Unemployment in Europe (London: Academic Press), pp. 199–206

The U.S. Net International Investment Position At The End Of 2014

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The U.S. Department of Commerce’s Bureau of Economic Analysis today released accounts for the United States’ international investment position. The U.S. is sometimes called the world’s biggest debtor and its net international investment position is now (at the end of 2014) minus $6.9 trillion.

Here’s the chart from the BEA’s website. U.S. Net International Investment Position 2014A few points. The importance of the U.S. balance of payments and international investment position is quite neglected in analysis of the crisis. The United States’ economy went into a crisis (and the rest of the world with it) because a huge rise in private indebtedness led to a fall in private expenditure relative to income when the burden of the debt started pinching. This caused a drop in economic activity and was saved partly due to automatic stabilizers of fiscal policy as tax payments fell due to a drop in economic activity and partly due to a relaxation of fiscal policy itself by the U.S. government and governments abroad. But the huge rise in the U.S. government debt meant that resolving the crisis by fiscal policy alone would have been difficult. This is because a huge fiscal expansion would have meant that the U.S. trade deficit would have risen much faster into an unsustainable path.

See Wynne Godley’s article The United States And Her Creditors: Can The Symbiosis Last? from 2005 here arguing such things.

Back to the international investment position. There are a lot of interesting things about it. Although the U.S. in a huge debtor to the rest of the world, the return on assets held by resident economic units of the United States earn more than paying on liabilities to nonresidents. So according to the BEA release U.S. International transactions 2014, investment income in the full year was about $813 billion while income payments was about $586 billion. (More complication arises from “secondary income”).BEA-2014-U.S.-International-Transactions

In addition, revaluations of assets and liabilities also affect the international investment position and revaluations of direct investment held abroad has acted in the United States’ favour.

Of course this cannot always be the case. Take a simple example: Suppose an economic unit’s assets is $100 and liabilities is $150 and suppose assets earn 8% every year and interest paid on liabilities is 5%. So even though the economic unit has a net indebtedness of $50, it is earning

$100 × 8% − $150 × 5% = $0.5

However, if liabilities rise to $160 and beyond the net return turns negative.

In a similar way, there is a tipping point, beyond which the net primary income of the current account of balance of payments turns negative. Because the United States has a negative current account balance and the deficit adds to the net indebtedness every year, at some point in the future, the international investment position may reach a tipping point.

All this sounds as if domestic demand and output are unrelated. This is of course not the case. Imports depend on domestic demand and exports depend on economic activity abroad. Hence the constraint on output at home because if output were to rise fast, the net indebtedness of the United States will also rise fast.

Of course the concept of a tipping point may itself be misleading. Indebtedness can keep rising even if net primary income turns negative without any trouble in financial markets because it all depends on how the financial markets see the problem. But it may be said that once a tipping point is reached, the debt will start to rise much faster than now. My article here hasn’t gone into any analysis here with numbers but I will leave it for another day.

Derailed: Wynne Godley On The Euro Area

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I am in favour of Britain having much closer ties with other European countries, provided that appropriate institutions are created and the whole thing is brought under effective political control. But I have never been able to understand what it is that those who support the Maastricht Treaty think they are going to get out of it. Maastricht supporters are keen on ‘not being left out’. But left out of what exactly?

…

It seems clear that the Maastricht criteria for the establishment of ‘convergence’ were far too narrowly conceived. To fulfil the conditions necessary for a successful currency union it is not nearly enough that member countries agree to follow simple rules on budgetary policy and achieve some minimum period of low inflation and currency stability. They need to reach a degree of structural homogeneity such that shocks to the system as a whole do not normally affect component regions in drastically different ways. Moreover, arrangements should be made which ensure that when substantial changes of a structural kind do turn up the federal authority is equipped to share out any burden which ensues. It would be wrong to suppose that there exist well-defined ‘fault lines’ which can be cured once and for all. Structural changes are always going to be taking place as a consequence of political earthquakes, or for other reasons, and the Community must have some way of dealing with them.

– Wynne Godley, Derailed, 1993

A list of articles by Wynne Godley on the Euro Area:

  1. ‘Commonsense Route To A Common Europe’, Observer,  6 January 1991, page 28 (scan)
  2. ‘Maastricht And All That’, London Review of Books, Vol. 14 No. 19, 8 October 1992, pages 3-4 (link)
  3. ‘Derailed’, London Review of Books, Vol. 15 No. 16, 19 August 1993, page 9 (link, more here)
  4. ‘Curried EMU – The Meal That Fails To Nourish’, Observer, 31 August 1997, page 24 (scan)

Wynne-Godley-July-1981Wynne Godley, July 1981
(picture source)

Greg Mankiw And Empirics

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Greg Mankiw wonders if teaching students empirics is feasible and answers in negative:

Noah Smith says introductory economics needs to be more empirical. I understand his argument, and have some sympathy with it, but I wonder if the substantial change he seems to be proposing is practical. Economists usually do empirical work with statistical tools that most college freshmen have not yet learned.

We teachers of introductory economics can and should explain where and why economists disagree. That is part of helping students develop their critical thinking skills. But I doubt students are in a position to try to evaluate the competing empirical work that shapes the differing views.

In the end, introductory economics is just that: an introduction to the economist’s way of thinking. That means giving students basic concepts–comparative advantage, supply and demand, market efficiency and market failure–that will make them more perceptive readers of the newspaper.

The failure to teach empirics to students and how it distorts their vision was well understood by Wynne Godley. In a 1993 article Time, Increasing Returns And Institutions In Macroeconomics, in S. Biasco, A. Roncaglia and M. Salvati (eds.), Market and Institutions in Economic Development: Essays in Honour of Paolo Sylos Labini, (New York: St. Martins Press), pp. 59-82 he wrote:

… But my objection goes beyond skepticism that the world we live in is being described realistically. My additional concern is that the NCP [neoclassical paradigm] is prejudicial with regard to the understanding of some of the most important processes going on in the world today. Thus in the ‘classical’ version of the NCP real output is determined by supply side alone; fiscal policy is entirely impotent and the government can only affect anything by changing the money supply; even then all it can do is affect the price level. The idea that fiscal policy is impotent, which seems to be based entirely on this model, has been extremely influential in contemporary political discussion; it is not just a provisional result suitable for a week or two in an elementary class.

Then the abolition of time prejudices the perception of inflation as an evolutionary process; the equilibria generate ‘explanations’ of price levels not changes, and theories of inflation cannot be convincingly coaxed forth. As if this were not enough, the whole construction leads by virtue of its axioms to the conclusion that wage and price flexibility, in combination with free trade, will generate full employment and convergence, if not equalisation, of living standards between countries and between regions within countries. In sum, while the absence of processes occurring in historical time means that the NCP does not encourage students to go and look up figures in books, if and when they are forced to do so their vision is likely to have been for ever distorted.

[emphasis added]

Steve Keen And Sectoral Balances

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Steve Keen has a new article on sectoral balances here.

First apologies in advance for sometimes criticizing heterodox economists more but needless to say, such criticisms are of a totally different nature than criticisms of mainstream economists.

Anyway, I am surprised at why Keen mixes accounting identities, especially when it involves banks in the analysis. In the new article, Keen has an equation:

 Bank lending p.a. = Nominal GDP growth / Velocity of Money + Government Deficit + Trade Surplus

I don’t get this. The correct sectoral balances equation (in a simplified three-sector setting) is:

Net Lending = Government Deficit + Current Account Balance of Payments

Here, net lending is that of the private sector. The terminology net lending is something national accountants use, while Wynne Godley used NAFA  — net accumulation of financial assets which means a slightly different thing in national accounts, but this point is irrelevant here.

Keen’s equation seems to mix many things and it has a term for GDP growth which actually needs a model and is not something that can be derived from an accounting identity. Morever, Keen seems to forever blur bank lending and lending in general and hopefully he gets these things right in the future. The hidden assumption in Keen’s models —something which has been pointed out by Nick Edmonds — is that non-bank lending has no effect on aggregate demand which (the assumption) doesn’t make sense.

The original sectoral balances identity was used by Wynne Godley with a behavioural model around it, although he started building his models when he realized in the 70s that the accounting identity itself is a great revelation. And a narrative around the three balances makes a good story especially for telling a story about future scenarios and so on.

Keen, on the other hand has a relation which is not really an identity but a behavioural equation. By itself there’s nothing wrong but given his mixing things up, it really ends up adding confusions. Keen’s blog title uses the phrase “arithmetic” which simply means a manipulation of numbers but has an equation which is more than arithmetic. Reading his article suggests that he has improved the sectoral balances to take into account bank lending. But the sectoral balances equation is an identity even if banks exists. And Keen seems to derive his equation as if it were an accounting identity.

Again goes on to show, it is highly important in macroeconomics to know flow of funds properly.

Tobinesque Models

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Paul Krugman writes today on his blog on James Tobin’s work:

Let me offer an example of how this ended up impoverishing macroeconomic analysis: the strange disappearance of James Tobin. In the 1960s Tobin developed and elaborated a sophisticated view(pdf) [original link corrected] of financial markets that offered insights into things like the role of intermediaries, the effects of endogenous inside money, and more. I’ve found myself using Tobinesque analysis a lot since the financial crisis hit, because it offers a sophisticated way to think about the role of finance in economic fluctuations.

But Tobin, as far as I can tell, disappeared from graduate macro over the course of the 80s, because his models, while loosely grounded in some notion of rational behavior, weren’t explicitly and rigorously derived from microfoundations. And for good reason, by the way: it’s pretty hard to derive portfolio preferences rigorously in that sense. But even so, Tobin-type models conveyed important insights — which were effectively lost.

Compare that to his article in response to another article on Wynne Godley which appeared in the New York Times – completely dismissing Godley’s work.

Three things: first Krugman claimed earlier that we needn’t look at old ideas:

But it is kind of funny to see a revival of old-fashioned macro hailed, at least by some, as the key to a reconstruction of the field

directly contradicting what he says today.

Second – obviously not having read Wynne Godley, he missed the point that Wynne’s analysis has significant improvement of James Tobin’s work.

Third, of course, Krugman’s understanding of monetary economics in general is poor, as can be seen when he gets into debates with heteredox economists and makes the most elementary errors. So it is strange he is lecturing others on this and fails once again to acknowledge heteredox economists.

Here’s Marc Lavoie describing in his article From Macroeconomics to Monetary Economics: Some Persistent Themes in the Theory Work of Wynne Godley in the book Contributions to Stock-Flow Modeling: Essays in Honor of Wynne Godley:

As Godley points out on a number of occasions, he himself owed his formalization of portfolio choice and of the fully consistent transactions-flow matrices to James Tobin. Godley was most particularly influenced and stimulated by his reading of the paper by Backus et al. (1980), as he writes in Godley (1996, p. 5) and as he told me verbally several times. The discovery of the Backus et al. paper, with its large flow-of-funds matrix, was a revelation to Godley and allowed him to move forward. But as pointed out in Godley and Lavoie (2007, p. 493), despite their important similarities, there is a crucial difference in the works of Tobin and Godley devoted to the integration of the real and monetary sides. In Tobin, the focus is on one-period models, or on the adjustments from the initial towards the desired portfolio composition, for a given income level. As Randall Wray (1992, p. 84) points out, in Tobin’s approach ‘flow variables are exogenously determined, so that the models focus solely on portfolio decisions’. By contrast, in Godley and Cripps and in further works, Godley is preoccupied in describing a fully explicit traverse that has all the main stock and flow variables as endogenous variables. As he himself says, ‘the present paper claims to have made … a rigorous synthesis of the theory of credit and money creation with that of income determination in the (Cambridge) Keynesian tradition’ (Godley, 1997, p. 48). Tobin never quite succeeds in doing so, thus not truly introducing (historical) time in his analysis, in contrast to the objective of the Godley and Cripps book, as already mentioned earlier. Indeed, when he heard that Tobin had produced a new book (Tobin and Golub, 1998), Godley was quite anxious for a while as he feared that Tobin would have improved upon his approach, but these fears were alleviated when he read the book and realized that there was no traverse analysis there either.

Draft link here.

On Models

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Ryan Decker has a blog post on DSGE models. Although I don’t like DSGE models, I think he has something nice to say about modeling:

We must get econ pundits to understand that we’re all using models, including non-economist bloggers, even if they’re not written down as mathematical expressions. Writing a model down in its entirety so that its assumptions are made explicit and its internal workings can be examined by anyone is an act of intellectual humility. It is baffling to me that people who write down their models formally so we can all argue about them are supposedly worse and more arrogant than those who think they can identify a narrative model’s assumptions and keep it internally consistent.

James Tobin had something similar to say in his 1982 Nobel lecture Money and Finance in the Macroeconomic Process (alternative link):

Theoretical macroeconomic models of one brand or another are very influential. They guide the architects of econometric forecasting models. They shape the thinking of policymakers and their advisers about “the way the world works.” They color the views of journalists, managers, teachers, housewives, politicians, and voters. Almost everyone thinks about the economy, tries to understand it, and has opinions on how to improve its performance. Anyone who does so uses a model, even if it is vague and informal.

[emphasis added]

In his 1999 paper Money And Credit In A Keynesian Model Of Income Determination, Wynne Godley says:

This paper takes a step in the right direction by incorporating EM [endogenous money] ideas into a complete, if very much simplified model of the whole economy. Writings on monetary theory commonly rely solely on a narrative method which puts a strain on the reader’s imagination and makes disagreements difficult to resolve. The narratives in this paper will all describe simulations which are grounded in a rigorous model, which will make it possible to pin down exactly why the results come out as they do.

Personally I find stock-flow consistent models extremely useful to think about the working of the world as a whole. It is when you sit down and work through the models, that you realize how complicated the whole thing is and how naive intuition isn’t good enough. Of course models aren’t the only way to study, so one needs a mix of models and a non-mathematical narrative and some empirical analysis to add colour to the story. It is true models have disadvantages but beware of people who just highlight the disadvantages and don’t know the advantages because their intuition is also a naive model of the world.