LARS P. SYLL

Why the notion of austerity is a massive failure

 

(h/t Jan Milch)

Om vikten av att skilja på risk och osäkerhet

På en punkt är det särskilt angeläget att uppgradera den finansiella kunskapen, och det är i förståelsen av osäkerhet …

Läroboken säger i praktiken att vi kan sopa osäkerheten under mattan. När den påstår att vi kan “precisera en sannolikhets-fördelning” försöker den om-vandla osäkerheten till risk …

Det är dags att inse hur farlig denna syn är. Finansmarknaderna är osäkra. Osäkerheten är inte kvantifierbar. Att försöka släta över osäkerheten och prata om risk som ett statistiskt mått är ansvarslöst, för i den sekund man formulerar en risksiffra är det många som börjar tro på den.

Bäst uttrycker kanske ändå postkeynesianernas grand old man – Paul Davidson – vikten och betydelsen av att som John Maynard Keynes (för att nu inte nämna Frank Knight och Gunnar Myrdal) skilja på probabilistisk risk och genuin osäkerhet:

Unfortunately as we have all learned in the world of experience, little is known with certainty about future payoffs of investment decisions made today. If the return on economic decisions made today is never known with certainty, then how can financial managers make optimal decisions on where to put their firm’s money and householder’s where to put their saving today?

If theorists invent a world remote from reality and then lived in it consistently, then Keynes [1936, p.16] argued these economic thinkers were “like Euclidean geometers in a non-Euclidean world who discover that apparent parallel lines collide, rebuke these lines for not keeping straight. Yet, in truth there is no remedy except to throw over the axiom of parallels and to work out a non-Euclidean geometry. Something similar is required to-day in economics” …

As any statistician will tell you, in order to draw any statistical (probabilistic risk) inferences regarding the values of any population universe, one should draw and statistically analyze a sample from that universe. Drawing a sample from the future economic universe of financial markets, however, is impossible. Simply stated the ergodic axiom presumes that the future is already predetermined by an unchanging probability distribution and therefore a sample from the past is equivalent to drawing a sample from the future … Assuming ergodicity permits one to believe one can calculate an actuarial certainty about future events from past data.

Efficient market theorists must implicitly presume decision makers can reliably calculate the future. The economy, therefore, must be governed by an ergodic stochastic process, so that calculating a probability distribution from past statistical data samples is the same as calculating the risks from a sample drawn from the future. If financial markets are governed by the ergodic axiom, then we might ask why do mutual funds that advertise their wonderful past earnings record always note in the advertisement that past performance does not guarantee future results …

This ergodic axiom is an essential foundation for all the complex risk management computer models developed by the “quants” on Wall Street. It is also the foundation for econometricians who believe that their econometric models will correctly predict the future GDP, employment, inflation rate, etc. If, however, the economy is governed by a non-ergodic stochastic process, then econometric estimates generated from past market data are not reliable estimates that would be obtained if one could draw a sample from the future …

In sum, the ergodic axiom underlying the typical risk management and efficient market models represents, in a Keynes view, a model remote from an economic reality that is truly governed by non-ergodic conditions. Keynes, his Post Keynesian followers, and George Soros all reject the assumption that people can know the economic future since it is not predetermined. Instead they assert that people “know” they cannot know the future outcome of crucial economic decisions made today. The future is truly uncertain and not just probabilistic risky.

Paul Davidson

Cypern som eurosystemrisk

Men det handlar inte om den direkta ekonomiska smällen som en krasch på Cypern orsakar. Hela det cypriotiska banksystemet är hälften så stort som svenska SEB.

Faran ligger i något helt annat. Ett tänkbart scenario som uppenbarligen diskuterats i EU-kretsar de senaste dagarna är att Cypern faktiskt lämnar valutasamarbetet. Därmed skulle eurobunkerns igenmurade nödutgång, den som en enig politikerarmé deklarerat måste förbli stängd om så helvetet startar skridskoskola, plötsligt börja stå och slå på vid gavel. Befolkningarna i Spanien, Portugal och andra krisländer skulle ju kunna få för sig ett och annat.

Skulle de försöka fly euron skulle det få desto större konsekvenser för Europa …

Precis så är det med hela eurokrisen. Intressen ställs mot varandra. Sunda principer möter en kompromisslös verklighet. Det som verkar klokt i Berlin låter sinnesjukt i Madrid, London eller Nicosia. För varje lösning på ett problem uppstår två nya. Och därför får också till synes små avgöranden oproportioneligt stor betydelse.

Andreas Cervenka

Det börjar med andra ord bli läge för Carl Bastiat Hamilton att åter föreslå att Sverige ska gå med i eurosamarbetet …

Inflation targeting – an unmitigated failure

The Riksbank in 1993 announced an official target for CPI inflation of 2 percent. Over the last 15 years, average CPI inflation has equaled 1.4 percent and has thus fallen short of the target by 0.6 percentage points. Has this undershooting of the inflation target had any costs in terms of higher average unemployment? This depends on whether the long-run Phillips curve in Sweden is vertical or not. During the last 15 years, inflation expectations in Sweden have become anchored to the inflation target in the sense that average inflation expectations have been close to the target. The inflation target has thus become credible. If inflation expectations are anchored to the target also when average inflation deviates from the target, the long-run Phillips curve is no longer vertical but downward-sloping. Then average inflation below the credible target means that average unemployment is higher than the rationalexpectations steady-state (RESS) unemployment rate. The data indicate that the average unemployment rate has been 0.8 percentage points higher than the RESS rate over the last 15 years. This is a large unemployment cost of undershooting the inflation target. Some simple robustness tests indicate that the estimate of the unemployment cost is rather robust, but the estimate is preliminary and further scrutiny is needed to assess its robustness.
…
During 1997-2011, average CPI inflation has fallen short of the inflation target of 2 percent by 0.6 percentage points. But average inflation expectations according to the TNS Sifo Prospera survey have been close to the target. Thus, average inflation expectations have been anchored to the target and the target has become credible. If average inflation expectations are anchored to the target when average inflation differ from the target, the long-run Phillips curve is not vertical. Then lower average inflation means higher average unemployment. The data indicate that average inflation below target has been associated with average unemployment being 0.8 percentage points higher over the last 15 years than would have been the case if average inflation had been equal to the target. This is a large unemployment cost of average inflation below a credible target. Some simple robustness tests indicate that the estimate of the unemployment cost is rather robust, but the estimate is preliminary and further scrutiny is needed to assess its robustness.

The difference between average inflation and average inflation expectations and the apparent existence of a downward-sloping long-run Phillips curve raises several urgent questions that I believe need to be addressed. Why have average inflation expectations exceeded average inflation for 15 years? Why has average inflation fallen below the target for 15 years? Could average inflation have fallen below average inflation expectations and the inflation target without the large unemployment cost estimated here? Could the large unemployment cost have been avoided with a different monetary policy? What are the policy implications for the future? Do these findings make price-level targeting or the targeting of average inflation over a longer period relatively more attractive, since they would better ensure that average inflation over longer periods equals the target?

Lars E.O. Svensson, The Possible Unemployment Cost of Average Inflation below a Credible Target

According to Lars E. O. Svensson – deputy governor of the Riksbank – the Swedish Riksbank has been pursuing a policy during the years 1998-2011 that in reality has made inflation on average 0.6 percentage units lower than the goal set by the Riksbank. The Phillips Curve he estimates shows that unemployment as a result of this overly “austere” inflation level has been almost 1% higher than if one had stuck to the set inflation goal of 2%.

What Svensson is saying, without so many words, is that the Swedish Fed for no reason at all has made people unemployed. As a consequence of a faulty monetary policy the unemployment is considerably higher than it would have been if the Swedish Fed had done its job adequately.

From a more methodological point of view it is of course also interesting to consider the use made of the rational expectations hypothesis in these model-based calculations (and models of the same ilk that abounds in “modern” macroeconomics). When data tells us that “average inflation expectations exceeded average inflation for 15 years” – wouldn’t it be high time to put the REH where it belongs – in the dustbin of history!

To me Svensson’s paper basically confirms what I wrote a couple of months ago:

Models based on REH impute beliefs to the agents that is not based on any real informational considerations, but simply stipulated to make the models mathematically-statistically tractable.

Of course you can make assumptions based on tractability, but then you do also have to take into account the necessary trade-off in terms of the ability to make relevant and valid statements on the intended target system.

Mathematical tractability cannot be the ultimate arbiter in science when it comes to modeling real world target systems. Of course, one could perhaps accept REH if it had produced lots of verified predictions and good explanations. But it has done nothing of the kind. Therefore the burden of proof is on those who still want to use models built on ridiculously unreal assumptions – models devoid of all empirical interest.

In reality, REH is a rather harmful modeling assumption, since it contributes to perpetuating the ongoing transformation of economics into a kind of science-fiction-economics. If economics is to guide us, help us make forecasts, explain or better understand real world phenomena, it is in fact next to worthless.

När dåliga prognoser är bättre än bra

Vad är värst, en dålig prognos eller ingen prognos? Svaret är enkelt. Så fort du exponeras för en prognos är du i en sämre position än du var innan …

Expertprognoser gör med all sannolikhet mer skada än nytta. Det är därför det lönar sig att snabbt bläddra förbi tidningsartiklar med rubriker som ‘Så kommer börsen gå i år’ …

Tänk dig att du har som jobb att sköta ditt företags valutaväxlingar … Du måste bestämma att antingen säkra växelkursen redan nu, eller vänta tills beloppet anländer och växla till den kurs som gäller då … Som tur är har du analytikernas dollarprognoser till hjälp. De gör det inte ett dugg lättare att förutspå dollarkursen. Men de kan hjälpa dig ändå.

Om du lyckas göra rätt spelar inte analyserna någon större roll. Men om dollarn faller som en sten och du har valt att inte säkra växelkursen, kommer företagsledningen att vilja veta varför du har sumpat bort företagets penga … Du kan dra en lång historia om historiska valutatrender, ekonomisk tillväxt, betalningbalans och ränteskillnader. Till slut kommer alla att hålla med om att du agerade rätt mot bakgrund av den information du hade på förhand.

Analyserna gör att du kommer undan. Särskilt de som hade mest fel … Prognoserna har inget ekonomiskt värde, vare sig för företaget eller samhället. Värdet är att de räddar ditt skinn.

Fondförvaltare Alf Riple – med bakgrund som chefsanalytiker på Nordea och rådgivare på norska Finansdepartementet – har skrivit en suveränt bra bok. Läs den!