A dynamic mon­e­tary multi-sec­toral model of pro­duc­tion

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I will be speak­ing at the Inter­na­tional Sci­en­tific Sym­po­sium for Devel­op­ment devoted to the 110th anniver­sary of Simon Kuznets in Kyev, The Ukraine, next week. Simon Kuznets, one of the few recip­i­ents of the faux Nobel Prize in Eco­nom­ics whose work I respect, was one of the pio­neers of empir­i­cal research in eco­nom­ics, a stu­dent of busi­ness cycles, and a critic of sta­tic eco­nomic method­ol­ogy.

My paper for this con­fer­ence is repro­duced below. It def­i­nitely deserves the label “wonkish”–in fact it’s cer­tainly the most wonk­ish thing I’ve ever posted here.

A dynamic mon­e­tary multi-sec­toral model of pro­duc­tion

Steve Keen, Uni­ver­sity of West­ern Syd­ney
Click here for the paper in PDF

Though Keynes enti­tled his mag­num opus The gen­eral the­ory of employ­ment, inter­est and money (Keynes 1936), he acknowl­edged that money did not fea­ture heav­ily in his tech­ni­cal analy­sis, and that he saw a sub­stan­tial con­ti­nu­ity between mon­e­tary analy­sis and the Mar­shal­lian model of sup­ply and demand:

whilst it is found that money enters into the eco­nomic scheme in an essen­tial and pecu­liar man­ner, tech­ni­cal mon­e­tary detail falls into the back­ground. A mon­e­tary econ­omy, we shall find, is essen­tially one in which chang­ing views about the future are capa­ble of influ­enc­ing the quan­tity of employ­ment and not merely its direc­tion. But our method of ana­lyz­ing the eco­nomic behav­ior of the present under the influ­ence of chang­ing ideas about the future is one which depends on the inter­ac­tion of sup­ply and demand, and is in this way linked up with our fun­da­men­tal the­ory of value. We are thus led to a more gen­eral the­ory, which includes the clas­si­cal the­ory with which we are famil­iar, as a spe­cial case. (Keynes 1936, p. xxii)

After Keynes, macro­eco­nom­ics frag­mented around the impor­tance of both uncertainty—implicit in the state­ment above that “chang­ing views about the future are capa­ble of influ­enc­ing the quan­tity of employ­ment”, but strongly explicit else­where (Keynes 1936; Keynes 1937)—and money. Both con­cepts dis­ap­peared from main­stream macro­eco­nomic analy­sis, to be replaced ini­tially by IS-LM analysis—in which an exoge­nously deter­mined money played a minor role, but uncer­tainty dis­ap­peared (Hicks 1937; Min­sky 1975; Hicks 1981)—and ulti­mately by Real Busi­ness Cycle mod­el­ing (Kyd­land and Prescott 1982), in which “ratio­nal expec­ta­tions” neutered uncer­tainty com­pletely (Lucas 1972), and money was entirely absent.

On the periph­ery of the pro­fes­sion, a rump of self-described “Post Key­ne­sians” clung to the posi­tion that both money and uncer­tainty were essen­tial aspects of macro­eco­nom­ics. Going far fur­ther than Keynes him­self, this rump incor­po­rated Schumpeter’s argu­ments on the essen­tial role of endoge­nously cre­ated money in financ­ing growth (Schum­peter 1927; Schum­peter 1934; Moore 1979) and Fisher’s debt-defla­tion per­spec­tive (Fisher 1933) to develop the “Finan­cial Insta­bil­ity Hypoth­e­sis” (Min­sky 1975; Min­sky 1977; Min­sky 1982; Min­sky 1993), while it also rejected Mar­shal­lian analysis—following on this issue Sraffa (Sraffa 1926; Robert­son, Sraffa et al. 1930) rather than Keynes. Oth­ers added insights from the­o­ret­i­cal devel­op­ments like com­plex­ity the­ory, which post-dated Keynes, to argue that the macro-econ­omy was inher­ently cycli­cal (Good­win 1967; Good­win 1986; Good­win 1990).

This rump was ignored by the main­stream, which over time expunged not only uncer­tainty and money but even Keynes him­self from macro­eco­nom­ics (despite the fact that the dom­i­nant seg­ment of the main­stream described its work as “New Key­ne­sian”). Main­stream macro­eco­nom­ics became applied neo­clas­si­cal micro­eco­nom­ics, as Oliver Blan­chard, found­ing edi­tor of the jour­nal AER: Macro, out­lined in his sur­vey of macro­eco­nom­ics in 2009.

The most vis­i­ble out­comes of this new approach are the dynamic sto­chas­tic gen­eral equi­lib­rium (DSGE) mod­els. They are mod­els derived from micro foundations—that is, util­ity max­i­miza­tion by con­sumers-work­ers; value max­i­miza­tion by firms; ratio­nal expec­ta­tions; and a full spec­i­fi­ca­tion of imper­fec­tions, from nom­i­nal rigidi­ties to some of the imper­fec­tions dis­cussed above—and typ­i­cally esti­mated by Bayesian meth­ods. (Blan­chard 2009, p. 223)

As the end of the first decade of the 21st cen­tury approached, the main­stream was tri­umphal. At the pol­icy level, it took the credit for the decline in eco­nomic volatil­ity since the early 1980s:

As it turned out, the low-infla­tion era of the past two decades has seen not only sig­nif­i­cant improve­ments in eco­nomic growth and pro­duc­tiv­ity but also a marked reduc­tion in eco­nomic volatil­ity, both in the United States and abroad, a phe­nom­e­non that has been dubbed “the Great Mod­er­a­tion.” Reces­sions have become less fre­quent and milder, and quar­ter-to-quar­ter volatil­ity in out­put and employ­ment has declined sig­nif­i­cantly as well. The sources of the Great Mod­er­a­tion remain some­what con­tro­ver­sial, but as I have argued else­where, there is evi­dence for the view that improved con­trol of infla­tion has con­tributed in impor­tant mea­sure to this wel­come change in the econ­omy. (Bernanke 2004; empha­sis added)

At the level of pure the­ory, a sim­i­lar con­tent­ment pre­vailed. Though he acknowl­edged one notable dis­senter (Solow 2008), Blanchard’s sur­vey was unequiv­o­cal:

The state of macro is good. (Blan­chard 2009, p. 210)

Few more poorly timed state­ments have ever been made by promi­nent econ­o­mists. This paper was first pub­lished online as a work­ing paper in August 2008 (Blan­chard 2008)—one year after the event that is now regarded as the begin­ning of the finan­cial cri­sis (New York Times 2007) and 8 months after the NBER’s date for the com­mence­ment of the Great Reces­sion (NBER 2011). Its pub­li­ca­tion as a jour­nal paper in May 2009 pre­ceded the NBER’s date for the end of this reces­sion by one month (a deci­sion that I expect will prove pre­ma­ture).

Blan­chard was forced into recant­ing his opti­mism less than a year later (Blan­chard, Dell’Ariccia et al. 2010). But while he crit­i­cized macro­eco­nomic pol­icy prior to the cri­sis, he remained a believer in neo­clas­si­cal the­ory itself:

Iden­ti­fy­ing the flaws of exist­ing pol­icy is (rel­a­tively) easy. Defin­ing a new macro­eco­nomic pol­icy frame­work is much harder… It is impor­tant to start by stat­ing the obvi­ous, namely, that the baby should not be thrown out with the bath­wa­ter. Most of the ele­ments of the pre-cri­sis con­sen­sus, includ­ing the major con­clu­sions from macro­eco­nomic the­ory, still hold. Among them, the ulti­mate tar­gets remain out­put and infla­tion sta­bil­ity. The nat­ural rate hypoth­e­sis holds, at least to a good enough approx­i­ma­tion, and pol­i­cy­mak­ers should not design pol­icy on the assump­tion that there is a long-term trade-off between infla­tion and unem­ploy­ment. Sta­ble infla­tion must remain one of the major goals of mon­e­tary pol­icy. Fis­cal sus­tain­abil­ity is of the essence, not only for the long term but also in affect­ing expec­ta­tions in the short term. (Blan­chard, Dell’Ariccia et al. 2010, p. 207; empha­sis added)

Blanchard’s unwill­ing­ness to coun­te­nance the pos­si­bil­ity that the Great Reces­sion may be a Kuhn­ian crit­i­cal anom­aly for neo­clas­si­cal macro­eco­nom­ics (Beze­mer 2011) is rep­re­sen­ta­tive of this school of thought:

Indeed, the extreme sever­ity of this great reces­sion makes it tempt­ing to argue that new the­o­ries are required to fully explain it… But … it would be pre­ma­ture to aban­don more famil­iar mod­els just yet. (Ire­land 2011, p. 1; empha­sis added)

As a rep­re­sen­ta­tive of the Post Key­ne­sian and com­plex­ity the­ory rump, and one of the hand­ful of econ­o­mists to fore­see the Great Reces­sion (Keen 1995; Keen 2000; Keen 2006; Keen 2007; Keen 2007; Beze­mer 2009; Beze­mer 2011), I could not dis­agree more with Blan­chard and his col­leagues. Though neo­clas­si­cal econ­o­mists believe they are being method­olog­i­cally sound in apply­ing micro­eco­nomic con­cepts to model the macro-econ­omy, deep research long ago estab­lished that this is a fal­lacy. The Son­nen­schein-Man­tel-Debreu con­di­tions alone estab­lish that even the micro­eco­nom­ics of demand in a sin­gle mar­ket can­not be derived by extrap­o­la­tion from the behav­ior of a sin­gle util­ity-max­i­miz­ing agent, let alone the macro­eco­nom­ics of the whole econ­omy. As Solow him­self noted in the paper cited in Blan­chard (2009, p. 210):

Sup­pose you wanted to defend the use of the Ram­sey model as the basis for a descrip­tive macro­eco­nom­ics. What could you say? …

You could claim that … there is no other tractable way to meet the claims of eco­nomic the­ory. I think this claim is a delu­sion. We know from the Son­nen­schein-Man­tel-Debreu the­o­rems that the only uni­ver­sal empir­i­cal aggrega­tive impli­ca­tions of gen­eral equi­lib­rium the­ory are that excess demand func­tions should be con­tin­u­ous and homo­ge­neous of degree zero in prices, and should sat­isfy Wal­ras’ Law. Any­one is free to impose fur­ther restric­tions on a macro model, but they have to be jus­ti­fied for their own sweet sake, not as being required by the prin­ci­ples of eco­nomic the­ory. Many vari­eties of macro mod­els can be con­structed that sat­isfy those basic require­ments with­out impos­ing any­thing as extreme and prej­u­di­cial as a rep­re­sen­ta­tive agent in a favor­able envi­ron­ment. (Solow 2008, p. 244; empha­sis added; see also Solow 2001 and 2003)

I cover the myr­iad flaws in neo­clas­si­cal macro­eco­nom­ics in much more detail in Keen 2011b; suf­fice it to say here that, far from it being unwise to “throw the baby out with the bath­wa­ter”, neo­clas­si­cal macro­eco­nom­ics should never have been con­ceived in the first place. The Great Reces­sion will hope­fully prove to be the Bib­li­cal eco­nomic flood needed to finally sink this super­fi­cially appeal­ing but fun­da­men­tally flawed vision of how the macro-econ­omy func­tions.

 

How do I fault thee? Let me count the ways

 

The flaws of neo­clas­si­cal macro­eco­nom­ics are almost too numer­ous to enu­mer­ate, but the key weak­nesses are:

  1. Treat­ing a com­plex mon­e­tary mar­ket econ­omy as a barter sys­tem;
  2. Assum­ing that the macro-econ­omy is either in equi­lib­rium (par­tial or gen­eral, per­fect or imper­fect), or that it will return to equi­lib­rium rapidly if dis­turbed;
  3. Mod­el­ing the entire econ­omy using “applied micro­eco­nom­ics” and ignor­ing social class, when the Son­nen­schein-Man­tel-Debreu con­di­tions (Son­nen­schein 1972; Son­nen­schein 1973; Kir­man 1989; Shafer and Son­nen­schein 1993) estab­lish that, as Kir­man put it:

    we may well be forced to the­o­rise in terms of groups who have col­lec­tively coher­ent behav­iour. Thus demand and expen­di­ture func­tions if they are to be set against real­ity must be defined at some rea­son­ably high level of aggre­ga­tion. The idea that we should start at the level of the iso­lated indi­vid­ual is one which we may well have to aban­don” (Kir­man 1992, p. 138);

  4. Oblit­er­at­ing uncer­tainty from macro­eco­nomic the­ory with the absurd propo­si­tion that a ratio­nal indi­vid­ual is some­one who can accu­rately fore­see the future—which is what “ratio­nal expec­ta­tions” really means;
  5. Per­sist­ing with a sim­plis­tic “money mul­ti­plier” model of money cre­ation when the empir­i­cal evi­dence against this model is over­whelm­ing (Holmes 1969; Moore 1979; Moore 1988; Kyd­land and Prescott 1990); and
  6. Ignor­ing the piv­otal roles of credit and debt in the macro-econ­omy.

All these flaws are absent from the non-neo­clas­si­cal rump—especially in the work of Min­sky. But what the rump lacks, in com­par­i­son to the neo­clas­si­cal main­stream, is a coher­ent math­e­mat­i­cal expres­sion of its model that is widely accepted within that school. In this paper I con­tribute to the devel­op­ment of such a model (though I appre­ci­ate that my model is a long way from being accepted by my peers) using a mod­el­ing framework—which I call Mon­e­tary Cir­cuit The­ory (MCT)—that, in con­trast to the neo­clas­si­cal litany of sins above:

  1. Treats the econ­omy as inher­ently mon­e­tary;
  2. Makes no assump­tions about the nature of equi­lib­rium and mod­els the econ­omy dynam­i­cally;
  3. Mod­els behav­ior at the level of social classes rather than iso­lated agents;
  4. Pre­sumes ratio­nal but not prophetic behav­ior: peo­ple in social classes act in what they per­ceive as their best inter­ests given infor­ma­tion avail­able, but do not attempt to fore­cast the future state of the econ­omy (and they can­not do so in any case, because of the well-known fea­tures of com­plex sys­tems);
  5. Mod­els the endoge­nous cre­ation of money by the bank­ing sec­tor in a pure credit econ­omy (later exten­sions will incor­po­rate fiat money cre­ation by gov­ern­ments); and
  6. Gives credit and debt the piv­otal roles in eco­nomic the­ory that the Great Reces­sion has shown they have in the real world.

 

A framework for monetary macroeconomics

 

At one level, MCT is decep­tively sim­ple: all demand in the macro­econ­omy is treated as orig­i­nat­ing in bank accounts, where, in accor­dance with the empir­i­cal lit­er­a­ture (Holmes 1969; Moore 1979, 1988; Kyd­land and Prescott 1990), the bank­ing sys­tem has the capac­ity to endoge­nously cre­ate new credit-based money. The devel­op­ment of the frame­work is described else­where (see Keen 2006b, 2008, 2009); here I will sim­ply illus­trate MCT with the finan­cial flows used in the model of the 19th cen­tury “free bank­ing” sys­tem in Keen (2010). The core of MCT is a tab­u­lar lay­out of the finan­cial rela­tions between the eco­nomic enti­ties in the model, where each col­umn rep­re­sents an aggre­gate bank account, and each row rep­re­sents oper­a­tions on and between those accounts.

Table 1: Sam­ple Finan­cial Flows God­ley Table

 

Assets

Lia­bil­i­ties

Equity

Account Name

Bank Vault

Firm Loan

Firm Deposit

Worker Deposit

Bank Equity

Sym­bol

BV(t)

FL(t)

FD(t)

WD(t)

BE(t)

Ini­tial con­di­tions

100

0

0

0

0

Lend Money

–A

A

Record Loan

A

Com­pound Debt 

B

Ser­vice Debt 

–B

B

Record Pay­ment

–B

Deposit Inter­est

C

–C

Wages

–D

D

Deposit Inter­est

E

–E

Con­sume

F+G

–F

–G

Repay Loan

H

–H

Record Repay­ment

–H

 

 

Using a sym­bolic alge­bra pro­gram, the place­hold­ers A to H are then replaced by suit­able func­tions:

The pro­gram then auto­mat­i­cally derives a set of dif­fer­en­tial equa­tions for this sys­tem, which can be ana­lyzed sym­bol­i­cally or sim­u­lated numer­i­cally:

This cov­ers the finan­cial side of the econ­omy. The real econ­omy is cou­pled to this via a price mech­a­nism (and links between the wages flow—which deter­mines employment—and invest­ment, which is not shown in the sim­ple model in Table 1, but which deter­mines the cap­i­tal stock in a larger model).

The price mech­a­nism is derived ana­lyt­i­cally in Keen 2010 (pp. 17–18), and cor­re­sponds to the exten­sive empir­i­cal lit­er­a­ture into how firms actu­ally set prices—which has noth­ing to do with mar­ginal cost and mar­ginal rev­enue (see Lee 1998, Blinder et al. 1998, and Keen & Stan­dish 2006 and 2010) but instead rep­re­sents a markup on the wage costs of pro­duc­tion

 

The real econ­omy itself is mod­eled using Goodwin’s growth cycle (Good­win 1967; see also Blatt 1983, pp. 204–216), but expressed in absolute val­ues (Employ­ment, Wages, etc.) rather than ratios (rate of employ­ment, wages share of out­put) as in Goodwin’s orig­i­nal model.

 

Applying the framework: a “corn economy” with a financial crisis

 

The sam­ple God­ley Table shown in Table 1 has to be extended to allow for invest­ment, which as Schum­peter argued is the sound basis on which the credit sys­tem endoge­nously cre­ates new debt-based money (Schum­peter 1934, pp. 95–101).

Table 2: God­ley Table for Corn Econ­omy Model

 

Assets

Lia­bil­i­ties

Equity

Account Name

Bank Vault

Firm Loan

Firm Deposit

Worker Deposit

Bank Equity

Sym­bol

BV(t)

FL(t)

FD(t)

WD(t)

BE(t)

Lend from Vault 

–A

A

Record Loan

A

Com­pound Debt 

B

Ser­vice Debt 

–C

C

Record Pay­ment

–C

Debt-financed Invest­ment

D

Record Invest­ment Loan

D

Wages

–E

E

Deposit Inter­est

F

G

-(F+G)

Con­sump­tion

H+I

–H

–I

Repay Loan

J

–J

Record Repay­ment

–J

 

This God­ley Table results in the fol­low­ing generic sys­tem of finan­cial flows:


The sub­sti­tu­tions for this table are show in Equa­tion ; the rates of lend­ing, invest­ment and loan repay­ment (respec­tively A, D and J in Table 2) are now func­tions of the rate of profit, and wage pay­ments (E) are now wages times employ­ment.



The basic causal cycle in the Good­win model (to which the finan­cial flows above are attached) is quite sim­ple. Cau­sa­tion flows from left to right in equa­tions to :

  • The level of the phys­i­cal cap­i­tal stock deter­mines the level of phys­i­cal out­put per year:


  • Out­put per year deter­mines employ­ment :


  • The rate of employ­ment deter­mines the rate of change of the money wage—thus link­ing the phys­i­cal sec­tor to the mon­e­tary sec­tor; in keep­ing with Phillips’s orig­i­nal inten­tions (and in con­trast to most macro­eco­nomic mod­els), the wage change func­tion includes a reac­tion to the rate of change of employ­ment and the level of infla­tion, as well as a non­lin­ear reac­tion to the level of employ­ment:


  • The money wage deter­mines the rate of change of the price level :


  • The mon­e­tary value of out­put minus wages deter­mines profit:


  • The rate of profit deter­mines invest­ment (and hence the amount of new credit money needed should desired invest­ment exceed profit) and invest­ment minus depre­ci­a­tion deter­mines the rate of eco­nomic growth :


  • The inte­gral of invest­ment deter­mines the cap­i­tal stock:


  • The rate of change of the employ­ment rate is the rate of growth minus the rates of growth of labor pro­duc­tiv­ity and pop­u­la­tion:


  • Equa­tions for growth in labor pro­duc­tiv­ity and pop­u­la­tion com­plete the model:


 

The rates of lend­ing (A), debt-financed invest­ment (D) and loan repay­ment (J) are mod­eled as non­lin­ear func­tions of the rate of profit, while the Phillips Curve is also a non­lin­ear func­tion of the level of employ­ment. The basic func­tion used in all cases is a gen­er­al­ized expo­nen­tial func­tion where the argu­ments to the func­tion are an (xc,yc) coor­di­nate pair, the function’s slope at that point s, and its min­i­mum m:


The com­plete model is described by a set of ten dif­fer­en­tial equa­tions:


Given suit­able ini­tial con­di­tions and para­me­ter val­ues, this highly non­lin­ear mon­e­tary model can gen­er­ate the styl­ized facts of the last 20 years of macro­eco­nomic data: an appar­ent “Great Mod­er­a­tion” in employ­ment and inflation—which was actu­ally dri­ven by an expo­nen­tial growth in pri­vate debt—followed by a “Great Reces­sion” in which unem­ploy­ment explodes, infla­tion turns to defla­tion, and the debt level—absent of bank­ruptcy and gov­ern­ment intervention—goes purely expo­nen­tial as unpaid inter­est is com­pounded.

Fig­ure 1: US Data 1980–2008

As a com­plex sys­tems model, the behav­ior of this sys­tem depends upon its ini­tial con­di­tions as well as upon its inher­ent dynam­ics. In Keen 2011 I used a set of ini­tial con­di­tions that resulted in both a Great Mod­er­a­tion and a Great Recession—with no change to the under­ly­ing para­me­ters of the system—to indi­cate that this model fits Minsky’s cri­te­ria for a suc­cess­ful model of cap­i­tal­ism:

Can “It”—a Great Depression—happen again? And if “It” can hap­pen, why didn’t “It” occur in the years since World War II? These are ques­tions that nat­u­rally fol­low from both the his­tor­i­cal record and the com­par­a­tive suc­cess of the past thirty-five years. To answer these ques­tions it is nec­es­sary to have an eco­nomic the­ory which makes great depres­sions one of the pos­si­ble states in which our type of cap­i­tal­ist econ­omy can find itself.(Min­sky 1982 , p. 5; empha­sis added)

Fig­ure 2: Sim­u­la­tion Results with uncal­i­brated con­stant para­me­ter val­ues

This model cap­tures the macro­eco­nomic expe­ri­ence of the last 2 decades far more effec­tively than any neo­clas­si­cal model. How­ever, the Holy Grail of eco­nom­ics has always been to model the com­plex dynamic process by which com­modi­ties are pro­duced using other com­modi­ties and labor. In the next sec­tion I show that a struc­tured exten­sion of this corn econ­omy model—with finan­cial flows deter­min­ing demand, and pro­duc­tion mod­eled using Goodwin’s growth cycle—can gen­er­ate a coher­ent dynamic mon­e­tary mul­ti­sec­toral model of pro­duc­tion.

 

A dynamic monetary multisectoral model of production

 

First a strong caveat: this model is very ten­ta­tive, and many refine­ments need to be made. How­ever even in its ten­ta­tive state, it shows that a mon­e­tary, dynamic mul­ti­sec­toral model of pro­duc­tion can be con­structed.

The model repro­duces the struc­ture of the pre­ced­ing corn econ­omy model, extended to mul­ti­ple com­modi­ties in both pro­duc­tion (with each sec­tor need­ing to pur­chase inputs from other sec­tors pro­por­tional to its desired out­put level), and con­sump­tion. I also address one of the weak­nesses of input-out­put analysis—that pur­chases within a sec­tor are not explic­itly shown—by the sim­ple expe­di­ent of split­ting each sec­tor in two. There are 4 sec­tors in this sim­ple “proof of con­cept” model (notion­ally Cap­i­tal Goods, Con­sumer Goods, Agri­cul­ture and Energy).

The God­ley Table for this sys­tem has 19 sys­tem states— Bank Reserve, Bank Equity and Worker Deposit accounts as in the sin­gle sec­toral model, plus two Deposit and two Loan accounts per sector—and 16 finan­cial operations—debt com­pound­ing, debt repay­ing, money relend­ing and wages pay­ment as in the sin­gle sec­toral model, plus one inter­sec­toral pur­chase for pro­duc­tion and one for con­sump­tion per sec­tor. A styl­ized rep­re­sen­ta­tion of these flows is given in Table 3 (the inter­sec­toral flows are only par­tially indi­cated).

Table 3: Styl­ized rep­re­sen­ta­tion of mul­ti­ec­toral God­ley Table

 
Assets Lia­bil­i­ties Equity
Account Bank Reserve Sec­tor 1 Loan Sec­tor 2 Loan Sec­tor 1 Deposit Sec­tor 2 Deposit Worker Deposit Bank Equity
Sym­bol BR(t) FL1(t) FL1(t) FD1(t) FD2(t) WD(t) BE(t)
Com­pound Debt A1 A2
Deposit Inter­est B1 B2
Wages –C1 –C2 C1+C2
Worker Inter­est –D –D
Invest­ment K E –E
Inter­sec­toral C –F F
Inter­sec­toral A –G G
Inter­sec­toral E –H H
Con­sump­tion K I –I
Con­sump­tion C –J J
Con­sump­tion A –K K
Con­sump­tion E –L L
Pay Inter­est –M M
Repay Loans N –N
Recy­cle Reserves –O O O
New Money P P

 

 

An extract from the actual God­ley Table for this sys­tem (as imple­mented in Math­cad) is shown in Fig­ure 3.

 

Fig­ure 3: 7 of the 19 columns in the mul­ti­sec­toral God­ley Table

The rate of profit is now net of inter­sec­toral pur­chases for each sec­tor, and of course there is a dif­fer­ent rate of profit in each sec­tor. Inter­sec­toral pur­chases of inputs dif­fer for each sec­tor, and are pro­por­tional to the labor input needed to pro­duce the required out­put in each sector—signified by where the first sub­script rep­re­sents the sec­tor pur­chas­ing the inputs and the sec­ond the sec­tor from which the inputs are pur­chased. Equa­tion shows the rate of profit for­mu­lae for the cap­i­tal goods and con­sumer good sec­tors:

 

As with the sin­gle sec­toral model, behav­ior in five cru­cial areas is mod­eled as a non­lin­ear response to a rel­e­vant vari­able:

  • The rate of change of money wages as a func­tion of the rate of employ­ment;
  • The time con­stant in invest­ment deci­sions as a func­tion of the rate of profit;
  • The time con­stant in loan repay­ment as a func­tion of the rate of profit;
  • The time con­stant in money relend­ing as a func­tion of the rate of profit;
  • The time con­stant in new money cre­ation as a func­tion of the rate of profit;

Table 4: Para­me­ters for Behav­ioral Func­tions

 

With the pur­chases of inter­me­di­ate inputs taken care of in the mon­e­tary demand com­po­nent of the model, pro­duc­tion in each sec­tor is mod­eled as lagged response to installed cap­i­tal, and employ­ment is a lagged response to out­put. The func­tions for the con­sumer goods sec­tor, which are rep­re­sen­ta­tive of those for the other sec­tors, are shown in Equa­tion :


The full model is a sys­tem of dif­fer­en­tial equa­tions, where n is the num­ber of sec­tors, and the first set of terms spec­i­fies the equa­tions in the finan­cial sect­sor, the sec­ond the equa­tions in pro­duc­tion, and the final equa­tion is for pop­u­la­tion growth. In this sam­ple 4-sec­tor model, this results in a sys­tem of 40 non­lin­ear ODEs.

 

Results

 

The rate of profit var­ied between sec­tors, and, once the sys­tem had set­tled into its limit cycle, ranged from 0.4% p.a. and 8.7%.

Fig­ure 4

The aggre­gate real rate of eco­nomic growth var­ied between minus 1 and plus 5 per­cent p.a., and growth fol­lowed a saw­tooth pat­tern:

Fig­ure 5

This shape cor­re­sponds with the styl­ized nature of the busi­ness cycle, as Blatt observed:

In the real world, upswings are slow; down­swings go with an almighty rush. In the words of Gal­braith:

The usual image of the busi­ness cycle was of a wave­like move­ment, and the waves of the sea were the accepted metaphor… The real­ity in the nine­teenth and early twen­ti­eth cen­turies was, in fact, much closer to the teeth of a rip­saw which go up on a grad­ual plane on one side and drop pre­cip­i­tately on the other…” (Blatt 1983, pp. 203–204, cit­ing Gal­braith 1975, p. 104)

The growth rate and the debt to out­put level moved together, and the debt ratio cycled between 50 and 110 per­cent of GDP.

Fig­ure 6

The dis­tri­b­u­tion of income was real­is­tic, though the dynam­ics were rather more volatile than in actual data:

Fig­ure 7

The rate of infla­tion was unre­al­is­tic, with a min­i­mum of 8 per­cent p.a. and a max­i­mum of 45 per­cent.

Fig­ure 8

These last two empir­i­cal weak­nesses prob­a­bly reflect the spec­i­fi­ca­tion for the Phillips curve, and the ten­dency of the model to oper­ate in over-full employ­ment (defined as a ratio of 1 in this sim­ple model) given the para­me­ters used for cap­i­tal­ist and banker behav­ior.

Fig­ure 9

Finally, finan­cial dynam­ics were an essen­tial part of this model: money is far from neu­tral in this model (and in the real world). Peri­ods of falling eco­nomic growth coin­cided with an increase in bank reserves, and a decline in the level of loans.

Fig­ure 10

 

Conclusion

 

Though this pre­lim­i­nary model has many short­com­ings, the fact that it works at all shows that it is pos­si­ble to model the dynamic process by which prices and out­puts are set in a mul­ti­sec­toral econ­omy. The fail­ure of the neo­clas­si­cal school to achieve this objective—which it has had since the time of Walras—may relate to the abstrac­tions it made with the inten­tion of mak­ing this process eas­ier to model. These devices—everything from Walras’s taton­nement, to ignor­ing the role of money—may in fact be why they failed. The real world is com­plex and the real econ­omy is mon­e­tary, and com­plex mon­e­tary mod­els are needed to do it jus­tice.

Given the com­plex­ity of this model and the sen­si­tiv­ity of com­plex sys­tems to ini­tial con­di­tions, it is rather remark­able that an obvi­ous limit cycle devel­oped out of an arbi­trary set of para­me­ter val­ues and ini­tial conditions—with most (but by no means all) vari­ables in the sys­tem keep­ing within real­is­tic bounds. A con­jec­ture is that this limit cycle is a man­i­fes­ta­tion of the well-known insta­bil­ity of an input-out­put matrix (Jor­gen­son 1960; Jor­gen­son 1960; Jor­gen­son 1961; Jor­gen­son 1961; Hahn 1963; Blatt 1983; Fleiss­ner 1990; Heester­man 1990; John­son 1993), com­bined with non­lin­ear rela­tions that reverse the insta­bil­ity prop­er­ties of the sys­tem as it diverges from its equi­lib­rium. This con­jec­ture was first made by Blatt in a dis­cus­sion of both the his­tor­i­cal evi­dence of the busi­ness cycle and the dual insta­bil­ity of the equi­lib­rium growth path:

At this stage of the argu­ment, we feel free to offer a con­jec­ture: The repeated devel­op­ment of an unsta­ble state of the econ­omy is asso­ci­ated with, and indeed is an unavoid­able con­se­quence of, the local insta­bil­ity of the state of bal­anced growth. (Blatt 1983, p. 161)

The pres­ence of mon­e­tary buffers—in the guise of deposit accounts—surely also plays a role in the system’s capac­ity, despite its insta­bil­ity, to stay within real­is­tic bounds, in con­trast to most (if not all) other dynamic mul­ti­sec­toral mod­els.

I doubt that Kuznets would have been sur­prised by the fail­ure of equi­lib­rium-ori­ented attempts to build dynamic mul­ti­sec­toral mod­els of eco­nomic growth, since he argued long ago that dynam­ics had to be dif­fer­ent to sta­t­ics, and in par­tic­u­lar that the fetish with equi­lib­rium had to be aban­doned:

Accord­ing to the econ­o­mists of the past and to most of their mod­ern fol­low­ers, sta­tic eco­nom­ics is a direct step­ping stone to the dynamic sys­tem, and may be con­verted into the lat­ter by the intro­duc­tion of the gen­eral ele­ment of change… Accord­ing to other econ­o­mists, the body of eco­nomic the­ory must be car­di­nally rebuilt, if dynamic prob­lems are to be dis­cussed effi­ciently…

… as long as sta­tic eco­nom­ics will remain a strictly uni­fied sys­tem based upon the con­cept of equi­lib­rium, and con­tinue to reduce the social phe­nom­e­non to units of rigidly defined indi­vid­ual behav­ior, its ana­lytic part will remain of lit­tle use to any sys­tem of dynamic eco­nom­ics… the sta­tic scheme in its entirety, in the essence of its approach, is nei­ther a basis, nor a step­ping stone towards a proper dis­cus­sion of dynamic prob­lems. Kuznets, S. (1930, pp. 422–428, 435–436; empha­sis added)

Yet the sta­tic approach—masquerading as dynam­ics via word games such as using the moniker “Dynamic Sto­chas­tic Gen­eral Equi­lib­rium” to describe bas­tardized Ram­say-Solow equi­lib­rium growth models—still dom­i­nate eco­nom­ics, even after the con­tin­u­ing dis­as­ter of the cri­sis of 2007. Part of the rea­son for this per­sis­tence, I believe, is the seduc­tive sim­plic­ity of the “Mar­shal­lian Cross” that forms the basis of edu­ca­tion in eco­nom­ics: it con­forms to Henry Menchen’s apho­rism that “Expla­na­tions exist; they have existed for all time; there is always a well-known solu­tion to every human problem—neat, plau­si­ble, and wrong”. For eco­nom­ics to escape the trap of sta­tic equi­lib­rium think­ing, we need an alter­na­tive foun­da­tion method­ol­ogy that is neat, plau­si­ble, and—at least to a first approximation—right.

I offer this model and the tools used to con­struct it as a first step towards such a neat, plau­si­ble and gen­er­ally cor­rect approach to macro­eco­nom­ics. A col­league has imple­mented the God­ley Table method for build­ing a dynamic model of finan­cial flows in a pro­to­type dynamic mod­el­ing pro­gram QED, which is freely down­load­able from my blog. A Math­e­mat­ica imple­men­ta­tion is being devel­oped as part of a project with the CSIRO, and it will also be freely avail­able from my blog when it is com­pleted. The ulti­mate objec­tive is to develop a stand­alone dynamic mon­e­tary macro­eco­nomic mod­el­ing tool that is more suited to finan­cial flows than exist­ing sys­tems dynam­ics pro­grams like Simulink (http://www.mathworks.com/products/simulink/), Ven­sim (http://www.vensim.com/) and Vis­sim (http://www.vissim.com/).

The global econ­omy was blindly led into our cur­rent finan­cial cri­sis by an eco­nom­ics pro­fes­sion that had deluded itself into the belief that such phe­nom­ena can­not occur. Hope­fully, dur­ing this cri­sis, mon­e­tary macro­eco­nomic dynam­ics will finally sup­plant the sta­tic method against which Kuznets inveighed so elo­quently at the start of capitalism’s pre­vi­ous great finan­cial cri­sis.

 

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Acknowledgements

This work results from a col­lab­o­ra­tive research effort between the United Nations Envi­ron­ment Pro­gram (UNEP) and CSIRO Sus­tain­able Ecosys­tems to estab­lish a regional report on Resource Effi­ciency: Eco­nom­ics and Out­look for Asia?Pacific. I thank Peter Humphreys of the UWS School of Account­ing (and pre­vi­ously Man­ager in the Group Account­ing Research and Pol­icy Sec­tion of the Com­mon­wealth Bank of Aus­tralia) for advice on bank­ing prac­tice.

About Steve Keen

I am Professor of Economics and Head of Economics, History and Politics at Kingston University London, and a long time critic of conventional economic thought. As well as attacking mainstream thought in Debunking Economics, I am also developing an alternative dynamic approach to economic modelling. The key issue I am tackling here is the prospect for a debt-deflation on the back of the enormous private debts accumulated globally, and our very low rate of inflation.
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  • kys

    Ho! Steve,

    This one is good. I like it.

    I’m not sure if I could ever reall under­stand it, but I’m sure it’s going to be a box office hit in the Ukrain­ian eco­nomic the­aters.

  • Aleshores

    When read­ing your papers, it sur­prises me the spread over (a long) time of the results of your model. It seems as if the forces mov­ing it were (or had to be) more lim­ited in time. Although I have read your intro­duc­tion to dif­fer­en­tial equa­tions solu­tions, it is dif­fi­cult to under­stand the con­se­quences for the model, it would be nec­es­sary to have an engi­neer knowl­edge of this math intru­ment.
    Thank you for your effort!

  • myne

    Steve, Per­haps your math is spot on, but you aren’t look­ing at it cor­rectly 😉
    Ie, take a look at the infla­tion chart. It swings wildly from 8–45%.

    But if we add a dec­i­mal, it starts to look very sim­i­lar to the real world. .8% to 4.5%.

    Or, per­haps it’s actu­ally the “infla­tion impulse”.

    Also, with sec­tors like agri­cul­ture, it’s impor­tant to note that there should always be a rel­a­tively steady demand. Let’s face it, we don’t eat more raw unprocessed com­modi­ties when there’s a boom. If your model could pri­ori­tise spend­ing to show whether it’s nec­es­sary or dis­cre­tionary, you might come a lot closer to the real world.

    Just some thoughts from some­one who’s not a math genius.
    I know that makes me least qual­i­fied to com­ment, but it can’t hurt to share a per­spec­tive that’s just look­ing at the lines on the graph, and not the equa­tions.

  • No, the per­cent­ages are cor­rect Myne;

    The issue is just that the para­me­ters inter­act to keep employ­ment near to above full lev­els, and with the Phillips Curve spec­i­fi­ca­tion that results in wage demands of up to 50% p.a., which feed through to the rate of infla­tion.

    The real prob­lem is the inter­de­pen­dency between the ini­tial con­di­tions in a sys­tem of 40 ODEs with about 100 para­me­ters. Another spec­i­fi­ca­tion could result in more real­is­tic infla­tion lev­els, but it would involve tweak­ing all the para­me­ters. Given the sen­si­tiv­ity of highly non­lin­ear mod­els to ini­tial con­di­tions and para­me­ter val­ues, I’m happy to live with that one devi­a­tion from real­ism until I can afford a super­com­puter to explore dif­fer­ent para­me­ter ranges.

  • conal

    @Steve
    While you are wait­ing for that super­com­puter, did any poten­tial model-tweak­ers apply on this scheme to your depart­ment?
    http://www.careers.uws.edu.au/page-100-New-Academic-Opportunities

    Also I’m sure your blog read­ers would sup­port a grid-com­put­ing project to get a ‘super­com­puter’ on the cheap.
    http://boinc.berkeley.edu/trac/wiki/VolunteerComputing

    I’d love to play around with your mod­els myself, but I’ve got more press­ing things to do…

  • Love the car­toon Conal! I’d for­got­ten about the PhD­Comics site.

  • TruthIs­ThereIs­NoTruth

    don’t need a super­compter if you have a clever search algo­rithm

    see the fol­low­ing link for some inspi­ra­tion

    http://en.wikipedia.org/wiki/Simulated_annealing

  • That was a bit of a joke TININT! Find­ing com­pat­i­ble ini­tial con­di­tions for a sys­tem of 40 ODEs sim­ply requires me to put the time aside. But I could do with a super­com­puter for run­ning Monte Carlo sim­u­la­tions with a wide range of para­me­ter val­ues.

  • @ Keen — arti­cle
    ” For eco­nom­ics to escape the trap of sta­tic equi­lib­rium think­ing, we need an alter­na­tive foun­da­tion method­ol­ogy that is neat, plau­si­ble, and—at least to a first approximation—right.”

    I am of the belief that we have two type of belief struc­tures and func­tion­al­i­ties where one would think that the two should be in some sort of bal­ance — and per­haps some­times that this is the case but at the present time the sta­tic sys­tem of think­ing is dom­i­nant in all mat­ters. These two think­ing modes have a cap­tured and innate rela­tion­ship which can only described as ‘con­tra­dic­tory com­ple­men­ta­tion’ as was ini­tially glimpsed after Heisen­berg, intro­duced his “Uncer­tainty Prin­ci­ple”, and where he rejected all imag­i­na­tion despite estab­lished cer­tain­ties in elec­tron place­ments by Borh and oth­ers..

    Think­ing needs to be founded in expan­sive com­plex­ity which is rich with philo­soph­i­cal analo­gies, dynamic com­plex­i­ties metaphors,etc., which have shown to be sen­si­tized to ener­getic or vital evo­ca­tions aris­ing from the con­tex­tual vol­ume. Call it the intu­itive or that which allows simul­tane­ity to be expe­ri­enced through the senses.

    Cur­rent think­ing is no doubt, a pri­ori, sta­tic, objec­ti­fied, and super­fi­cial due to its very nature, or as the health food indus­try would call it “dead in the mouth” and is not expan­sive while forced to focus on sin­gu­lar­ity. It is Yes, rea­soned but on a plane and does not carry the impulses derived from being seen; it is point, lin­ear; super­fi­cial and not of vol­ume.

    From my lim­ited read­ing of Min­sky I believe his Mind could see, feel and hear; that is, com­pre­hend the signs of the dynamic thought processes and I now believe that you also, by this arti­cle, cer­tainly indi­cate strong signs of mov­ing into dynamic think­ing or, have pre­sented in such an expres­sion.

    Of course, such dynamic and vol­u­met­ric thought processes brings much more data into the fray — much more and as such these increased com­plex­i­ties and vis­i­ble inter­plays, need to be fol­lowed to their resul­tant sim­pli­fi­ca­tions, where, once arrived at, can eas­ily be re-tracked like spoor to cap­ture the beasts of con­text, ie the solu­tion to the phe­nom­ena; its nature and char­ac­ter­is­tics. Or, if you pre­fer, once the ques­tion has been fully con­structed, the answer is redun­dant.

    I believe I see a major shift now in your think­ing (or the pre­sen­ta­tion thereof) and it is good for it is in the dynamic arena where intel­lect is found; the epis­te­mo­log­i­cal neces­sity — while mere intel­li­gence is held in fas­ci­na­tion by the sta­tic state of mind — the mind processes of the col­lec­tives which really don’t do any­thing except act out the ‘Recur­sive game’ ad infini­tum.

    The image below is an ancient image / sym­bol of the ‘con­tra­dic­tory com­ple­men­ta­tion’ of think­ing man and his innate pow­ers of oppo­si­tions which are to be mas­tered — held on the hor­i­zon­tal field of the earthly ener­gies.

  • Another com­ment which I would like to make briefly is the value of group sta­tis­tics. Nat­u­rally these sta­tis­tics are of some use­ful guide but they belong to a col­lec­tive which has its own func­tion, nature, being, pur­pose, behav­iours, attrib­utes, iden­tity and ener­gies, where none of which belong to human beings; it is new. Indeed the col­lec­tive as seen in its cor­rect light, is the holis­tic sum of aggre­gated ener­gies which must be treated as a ‘whole’ and as such an unique emer­gent phe­nom­e­non, which owns its own par­a­digm that is dif­fer­ent to that of any of its con­stituents parts. (Eric Hof­fer pro­vides excel­lent insights in these mat­ters).

    And, ‘time’ is a man con­trived scalu­lar ref­er­ence to which peo­ple tend to treat with their own unique cir­ca­dian inter­pre­ta­tion (or con­tempt) and so the col­lec­tive, but not as innate, but as inher­ent; — ‘time’ is there­fore widely vari­able to the sta­tis­ti­cal source and not so widely vari­able to the indi­vid­ual — but vari­able nev­er­the­less.

    Add to this the dys­func­tional abil­i­ties of most bureau­cra­cies that pro­vide the data inputs known as indi­ca­tors, mostly lag­ging indi­ca­tors and lack of atten­tion to pre­ci­sion, cor­rect­ness and for­mu­la­tions, plus the manip­u­la­tions by the polit­i­cal con­ve­nience and whim in deter­mi­na­tion of the fun­da­men­tal Index, such as Infla­tion, Unem­ploy­ment, GDP, GNP, etc, there is a lot to be ques­tioned in the data in. (Garbage in, garbage out — extrap­o­la­tions and unknown unkl­nowns)

    Here as you say, you are run­ning 40 ODE’s with 100 para­me­ters all I assume with ini­ti­a­tion con­di­tional con­flicts with­out a super-com­puter which although said in jest, I doubt much dif­fer­ent in the results. What you appear to com­put­ing are col­lec­tive prob­a­bil­i­ties.

    Fish schools and bird flocks can turn on a dime, an humans just like sheep tend to be unpre­dictable and stub­bornly resis­tant to past per­for­mance.

    But then, you have much courage Steve, and that is good.

  • Per­haps you all will remem­ber my oft’ asked ques­tion as relat­ing to Aus­tralians, that is to say, of the ordi­nary earthly type: 

    Where is the Min­ing Boom???????????????

    From House and Holes — Please read the whole arti­cle:

    Mar­tin Parkin­son, the new Sec­re­tary of the Trea­sury — asks the same ques­tion — OK as an infer­ence but it is fairly explicit — espe­cially, as he appears to have no answers. — as he reflects in such a typ­i­cal response from our arro­gant Bureau­cracy.

    Are we to be con­tin­ued in this state of con­dem­na­tion by these sad incom­pe­tents of Hanlon’s Razor?

    It also seems to me to be too late as the our gov­ern­ment have sold all our alter­na­tives and burnt all our bridges.

    Note the Big 4 TBTF Bank down­grade today?

    “How will the ben­e­fits of the boom in the terms of trade be shared through the com­mu­nity? After all, today we are swap­ping a non-renew­able cap­i­tal asset – min­eral and energy reserves – for an income stream. If we don’t receive an appro­pri­ate return, and invest that wisely to build human and phys­i­cal cap­i­tal, and to boost national sav­ings, includ­ing through super­an­nu­a­tion, we could find our­selves hav­ing con­sumed our assets and be faced with lower future incomes.”

    http://macrobusiness.com.au/2011/05/parko-poses-conundrum-for-self/

    Sad really, but then we are are just still no more than “can­non fod­der”.

  • As afore­said:

    IN a blow to the Aus­tralian bank­ing indus­try, rat­ings firm Moody’s Investors Ser­vice down­graded the debt rat­ings of the country’s four largest banks, cit­ing their depen­dence on global lend­ing mar­kets.

    A down­grade to Aa2 from their pre­vi­ous invest­ment grade rat­ing of Aa1 — one notch below Moody’s top rat­ing — will likely increase their costs even as wor­ries grow that Australia’s ris­ing inter­est rates will crimp prof­itabil­ity.”

    http://www.theaustralian.com.au/business/industry-sectors/moodys-downgrades-anz-commonwealth-bank-westpac-nab/story-e6frg96f-1226058376936

    Widely reported.

    Obvi­ous this takes all doubt out of the Glen Steve’s next rate hike in early June (IMO), despite nation wide pleas for the con­trary. With the keen (no pun intended;-) inter­na­tional com­pe­ti­tion for whole­sale money — the need to, at least, try to stop the rapid decline in Aus­tralian house prices — the urgent Pol­icy to save the Banks asset val­ues — on-book and off-books — while attend­ing to rep­u­ta­tions and arro­gance, rais­ing inter­est rates will, or it is hoped, will, attract more hot money flows into for­eign deposit accounts that the Banks can uti­lize for their hous­ing growth lend­ing. (There is no other card to play).

    This Moody’s down­grade will most likely guar­an­tee a rate rise, and then another and then another because that is obvi­ously Gov­ern­ment / RBA Pol­icy, a pri­ori, and an action that Mr Stevens is well versed at.

    But, we shall see!

    What? Where is the Min­ing Boom? Not for the likes of you Mate, mind your busi­ness and move along!

    Com­ing soon…

  • Steve,

    My prin­ci­pal objec­tion to your Multi-Sec­toral Model is your equa­tion (1.6)
    K/v = Y where K is phys­i­cal cap­i­tal and Y is phys­i­cal out­put. Since Y = MV/p is a func­tion of the price level, then K/v must be a func­tion of price level as well. Since K is phys­i­cal cap­i­tal (inde­pen­dent of p) then v must be = v℗ = pv(1).

    To put a fine point on it, do you reject the exchange equa­tion pY = MV? Why?

    I attach the so-calledMar­ginal Pro­duc­tiv­ity of Debt which is drawn from BLS data and shows d(GDP)/d(debt). How do you explain it? It is sim­ply 1/v℗ ie. ,

    1/(pv(1)) is it not?

  • Jim.Whitman

    Just a worry, but I sub­scribe to the RSS feed from this web site but this arti­cle didn’t appear.

  • ak

    War­ren,

    The Fisher’s equa­tion does not any value in describ­ing the real­ity because the veloc­ity para­me­ter is not con­stant. There­fore you can­not draw any con­clu­sions from the quan­tity of money in the sys­tem. Another issue is how you define money — is it M1 or M2 or M3…?

    http://upload.wikimedia.org/wikipedia/commons/4/47/M2VelocityEMratioUS052009.png

    MV=PQ is always true by the def­i­n­i­tion of V (the aver­age fre­quency of all trans­ac­tions). It is a tau­tol­ogy.

    http://en.wikipedia.org/wiki/Equation_of_exchange

  • I reject the Fisher equa­tion War­ren, as we dis­cussed back in Chicago last year. As AK says, it is highly vari­able, and not casual link at all.

  • I’ll check it out Jim.

  • Bet­ter late than never, I guess, and “sum­mer” starts in a few weeks in the US.

    From Mish:

    … Lak­sh­man Achuthan at the ECRI who says “Global Slow­down to Hit by Sum­mer, Even for U.S.”

    http://globaleconomicanalysis.blogspot.com/2011/05/ecri-says-global-slowdown-will-hit-this.html

    There is a video here as well as the Mish com­ments.

    Com­ment:

    I chal­lenge the “Even in the US” bit — as that part is the Prime dri­ver.

    Now,

    Ques­tion: Just which coun­try will attract avail­able hot money, er, and how? 

    Answer: Aus­tralia. By jack­ing up inter­est rates, buy­ing more RMBS and con­vert­ing the Government’s (read: Nation’s)‘implicit ’ guar­an­tees on all for­eign deposits into ‘explicit’ Gov­ern­ment guar­an­tees.

    Plenty of fun in the pipe as yet.

    Suf­fer­ing is but another name for the teach­ing of expe­ri­ence,
    which is the par­ent of instruc­tion and the school­mas­ter of life.”
    — Horace [Quin­tus Hor­atius Flac­cus] (65-8BC) Roman poet

    LOL

  • DrBob127

    War­ren,

    That is a very inter­est­ing graph that you posted and a bit scary.. is there fur­ther his­tor­i­cal data?

  • Dr Bob,

    The link in my first post gives some sources for the data. The fact that this ratio, the out­put to cap­i­tal ratio, ? = ?℗, declines with ris­ing price level sup­ports the claim that real out­put is non-neu­tral with respect to infla­tion. If one assumes con­stant 4.5% infla­tion since 1940, the price level in 1966 was in the 4 to 5 range, and is presently in the 27–30 range. ? can be > 1 and was around 3 before 1940.

    I think that ?℗ = 3/p is in the right ball­park.

  • Econ­o­mists” as “Lead­ers”:

    WA State Government’s answer (Today’s MSM reports) to rapidly increas­ing infla­tion through­out the State — Jerk up (read: con­tinue to… ) Util­ity charges across the State another 5% to 8% so as to screw the masses (read: Qu’ils man­gent de la brioche) — You had to guess that the Pre­mier is an Econ­o­mist — so he cer­tainly knows how to squeeze the tears out of stones.

    While there has been a pub­lic hous­ing cri­sis in WA for years, it appears just now that all/most of the vacant pub­lic hous­ing just gets left aban­doned and derelict for years while the many ‘000’s home­less wan­der the streets — wait­ing.

    Like the last incom­pe­tent, he takes calls only from the Min­ers and the Bankers.

    Where is the Min­ing Boom?

  • REPOST TO CORRECT Apolo­gies to all

    Dr Bob,

    The link in my first post gives some sources for the data. The fact that this ratio, the out­put to cap­i­tal ratio, 1/v = 1/v℗, declines with ris­ing price level sup­ports the claim that real out­put is non-neu­tral with respect to infla­tion. If one assumes con­stant 4.5% infla­tion since 1940, the price level in 1966 was in the 4 to 5 range, and is presently in the 27–30 range. 1/v℗ can be > 1 and was around 3 before 1940.

    I think that 1/v℗ = 3/p is in the right ball­park.

  • Here is my Good­win model of US econ­omy since 1913. Of course I assume, like Hume and Ricardo, that PQMV.

    An inter­est­ing result is the con­nec­tion of the Vol­cker inter­est rate squeeze 1979–83 to the hous­ing boom that starts in 1997. The inter­est rise led to a wage share recov­ery which led to a reces­sion start­ing in the 80s. The recov­ery from this reces­sion caused a sec­ondary wage share bounce which, along with low inter­est rates, led to the hous­ing bub­ble.

  • alain­ton

    @steve

    Inter­est­ing model, ive never been able to under­stand why sen­si­ble use of sys­tems dynam­ics is so woe­fully under­used in eco­nom­ics.

    Im sure your aware of Kaleed Saeds inter­est­ing sys­tems dynam­ics recon­struc­tions of var­i­ous clas­si­cal econ­o­mists in ven­sim
    http://www.wpi.edu/Images/CMS/SSPS/LIMITS_08.pdf

    Some com­ment — the sim­ple markup approach — though empir­i­cally true would it not be more pow­er­ful to apply a ‘resource based the­ory of the firm’ approach — as in Lippman/Rumelt 2003 (less crudely aus­train than some resource based the­o­ries) — con­sis­tent with your wider cri­tique of the the­ory of the ‘rep­re­sen­ta­tive firm’.
    http://www.citeulike.org/user/derchao/article/3890033

    This woulden­able mod­el­ling by sec­tor of degree of monop­oly in the Kaleck­ian sense, as well as dynamic mod­el­ling of Schum­peter­ian swarm­ing effects etc. Would this pro­vide a bet­ter micro/macro bridge? 

    Sec­ondly why not include hous­ing as a sec­tor — if the sim­pli­fy­ing assump­tion was made of hous­ing = urban and rural = agri­cul­tural you could model some cantillon/new eco­nomic geog­ra­phy type inter­ac­tions.

    Oh that reminds me. It seems Krug­man, with Egger­son, has done some­thing of a Fisher style mea culpa about debt and his debitors=creditors what does it mat­ter state­ment.

    http://www.frbsf.org/economics/conferences/1102/eggertsson.pdf

    The model, though usu­ally mod­el­ling koo bal­ance sheet effects, still seems too new keyn­sian though, it requires an exoge­nous shock to cre­ate a down­swing whereas yours doesn’t.

    They still ulti­mately main­tains a debtors=creditors dogma which is eas­ily dis­missed.

    Imag­ine two banks alpha and beta, both have an ini­tial endow­ment of 20 mil­lion and lend to each other with inter­ests on invest­ments of 20 mil­lion a year. Both lend to a prop­erty firm Iznop land 200 mil­lion between them, 80% of val­ued asset price, with a return of 20 mil­lion per year over x years. Now Iznop land crashes, it paid too much and the banks over­val­ued the asset, which is now only worth 50% of what they thought. Hav­ing lent 200 mil­lion for an asset now only worth 100 mil­lion they are both 50 mil­lion in the red. The accoun­tants at each firm say they would be trad­ing unlaw­fully if they con­tin­ued to pay their loans to the other bank, as both are tech­ni­cally insol­vent and you can­not cap­i­talise a pro­jected income stream from another tech­ni­cally insol­vent body. 

    This demon­strates two things. Firstly the sum of credit and debit in an econ­omy is an iden­tity only if rever­sion­ary assets on loans is cor­rectly priced. Sec­ondly where firms and banks loan to each other the pos­si­bil­ity of bal­ance sheet con­ta­gion exists — even though — as here — all alpha and beta banks need to do to get back in busi­ness is can­cel each oth­ers loans, within 2 1/2 years both banks would be back in the red.

  • Steve and AK,

    Please note the Wage Share chart posted today on Max Keiser (below) and com­pare to my dynamic model posted prior.

    I am quite pleased with my Good­win model cor­rectly mod­i­fied for inflation/deflation which is posted here:http://johanraft.wordpress.com/the-results/

    It seems to me that vari­abil­ity of veloc­ity can be accounted for by %Employ­ment and that the Veloc­ity curve shown by the Mar­ginal Pro­duc­tiv­ity of Debt I posted ear­lier could be approx­i­mately 3*E/p