경제 현상에 대한 수학적이고 평형적인 모형은 인과적이고 현실적인 인간 행동의 양상을 담아내지 못한다.
노벨상을 받은 직후 앵거스 디튼Angus Deaton은 무작위 통제 실험(randomized controlled trials RCTs)이 작은 실험실에서 행해지는 것으로 외부적 가치가 없다고 불평했다. 즉 다른 환경에 적용될 수 없다는 말이다.
실험에 의존하는 연구자들은 경제의 주요 이론을 탐구하는 대신, 점점 더 작은 문제들을 이해하는데 집중하고 있다.
Randomized Controlled Trials and Economic Questions
Peter G. Klein
The Austrians have long argued that mathematical, equilibrium models of economic phenomena cannot capture the causal, realistic aspect of human behavior. "All things are subject to the law of cause and effect," says Menger in the famous opening line of his Principles of Economics. Formal models, in contrast, depict systems of equations in which each variable simultaneously determines the values of the other variables.
And yet, mainstream empirical economics has undergone a radical shift in the last two decades, moving away from reduced-form, atheoretical, equilibrium-based models and embracing newer approaches that purport to capture causality. This movement, described as the "credibility revolution," holds that social scientists can identify cause-and-effect, not through a priori reasoning as in Mises's approach, by adopting the methods used in biomedical research. Through careful research design, one can use experimental methods to identify factors or variables that "cause" particular outcomes, even without knowing the underlying mechanisms in a deep or intuitive sense. For example, to find out if workers supply a greater quantity of labor in response to an increase in the wage rate, one designs an experiment in which a "treatment" (an increased wage) is applied to one group of workers while another group, chosen to match the characteristics of the first, gets the "control" or placebo treatment (no wage increase). If the two groups are carefully matched on all characteristics other than wage rates thought to affect labor supply or, even better, groups of workers are randomly assigned to the treatment or control group, any differences in hours worked can be attributed to the change in wage. Careful matching (through observed characteristics or propensity scores) or random assignment takes care of the ceteribus paribus condition that, in the older approaches, would be handled through multiple regression. If there is a statistically significant difference in outcome between the two groups, the treatment can be said to "cause" the outcome.
Of course, this is a different concept of causation than Menger's or Mises's. Even within the mainstream, however, there has been some pushback against what some describe as a fetish with causal inference. Shortly after receiving his Nobel prize, Angus Deaton complained that randomized controlled trials (RCTs), most famously associated with MIT's Poverty Action Lab, were being asked to do too much -- what works in a small, experimental setting may have little "external validity," i.e., may not apply to other settings. George Akerlof recently observed that the emphasis on research design may come at the expense of the importance of the underlying economic question (a point I have also made). RCT enthusiasts have been called randomistas, not always as a compliment.
These critiques get at a fundamental point that has bothered me for some time. The increasing popularity of RCTs, instrumental variables models, differences-in-differences regressions, propensity score matching, regression discontinuity, and similar research designs seems to have coincided with a narrowing of focus. Rather than pursuing the big questions of economic theory, empirical researchers are applying more and more effort to understanding smaller and smaller questions -- what procedures get students study harder for a test? How does race or gender affect the number of job offers? These are a far cry from the kinds of questions that have motivated economists throughout the centuries.
This month's British Journal of Medicine features a hilarious send-up of RCTs in the form of a study, "Parachute Use to Prevent Death and Major Trauma When Jumping From Aircraft." Because the common belief that one should not jump out of a plane without a parachute is based merely on "biological plausibility and expert opinion," an RCT was designed to test for a true causal effect. After randomly assigning test subjects into parachute and no-parachute groups, the researchers could not detect a statistically significant treatment effect -- exactly the same number of jumpers was killed or injured in each group, namely zero, because the subjects were jumping out of small planes parked on the tarmac. Despite the potential lack of "external validity," the researchers (properly, according to the tenets of RCTs) conclude that there is no benefit to wearing a parachute when jumping out of a plane.
Peter G. Klein is Carl Menger Research Fellow of the Mises Institute and W. W. Caruth Chair and Professor of Entrepreneurship at Baylor University's Hankamer School of Business.
------------------------------------------------------
유럽중앙은행의 양적 완화는 실패였다.
유로존의 문제는 유동성이 아닌 정부 개입에서 초래된 것이다.
유로화의 양적 완화 이후로 GDP에 대한 정부 부채는 86.8%로 상승했다.
유럽은행의 양적완화의 최대의 성공은 저축가들을 희생시키고 정부에 대규모 구제금융을 퍼부은 것이다.
The ECB’s Quantitative Easing Was a Failure — Here Is What It Actually Did
Daniel Lacalle
The main reason why the ECB quantitative easing program has failed is that it started from a wrong diagnosis of the eurozone’s problem. That the European problem was a demand and liquidity issue, not due to years of excess.
The ECB had been receiving tremendous pressure from banks and governments to implement a similar program to the US’ quantitative easing, forgetting that the eurozone had been under a chain of government stimuli since 2009 and that the problem of the euro-zone was not liquidity, but an interventionist model.
The day that the ECB launched its quantitative easing program, excess liquidity stood at 125 billion euro. Since then it has ballooned to 1.8 trillion euro.
“Only” after 2.6 trillion euro purchase program and ultra-low rates.
Eurozone PMIs are atrocious. The euro-zone index falls from 52.7 in November to 51.3 in December, well below the consensus forecast of 52.8. More importantly, France’s PMI plummeted from 54.2 in November to a 34-month low of 49.3.
Unemployment in the euro-zone, at 8%, is double that of the US and comparable economies. Youth unemployment rate remains at 15%.
Economic surprise has plummeted as the ECB balance sheet reached 41% of GDP (vs 21% of the Fed).
More than 900 billion euro of non-performing loans remain in the banking system, which keeps a trillion euro timebomb in its balance sheets (read). A figure that represents 5.1% of total loans compared to 1.5% in the US or Japan.
Deficit spending is rising. Government debt to GDP has risen to 86.8%.
The number of zombie companies -those that cannot pay interest expenses with operating profits- has soared to more than 9% of all large quoted firms, according to the BIS.
Sovereign states have saved around one trillion euro in interest expenses, but have spent all those savings. Today, almost no eurozone country can absorb a modest rise in interest rates, and Italy, Spain, France, Portugal, Slovenia, and others are demanding more spending and more deficits.
There is no real secondary market demand for eurozone sovereign bonds at these yields. At the peak of its quantitative easing program, the Federal Reserve was never the sole buyer of Treasuries. There was always a relative secondary market. In the Eurozone, the ECB has been 7 seven times the net issuances of sovereigns. No investor is likely to buy eurozone sovereign bonds at these yields once the ECB steps down.
Eurozone growth and inflation estimates have been revised down again in December. Industrial production has fallen sharply.
Trichet, the ECB’s predecessor to Mario Draghi, had lowered interest rates from 5% to 1%, injected billions into the economy, buying sovereign bonds in 2011.
What has the ECB been successful at?
*Keeping the euro alive. Not a small success, by the way. The risk of break-up has been contained but not eliminated.
*Maintaining government spending at low rates. However, at the expense of savers and salaries.
*Generating a sense of euphoria in financial markets, with high yield and sovereign bonds soaring.
*Wages in the euro-zone have increased below inflation since QE launched and into the third quarter of 2018. In fact, low inflation has been the biggest unintended success of the ECB. It could have been worse.
*The biggest “success” of the ECB has been the massive bailout of governments at the expense of savers.
도표 생략
We also have to agree that Mario Draghi has been reminding governments that they needed to implement structural reforms, use the period of low rates to deleverage and repeating constantly that monetary policy will not work without reforms. No one listened. It was party time, and cheap money attracts bad decisions.
A Never-Ending Government Stimulus
With public spending averaging over 46% of GDP, an annual deficit of over 1.7% on average, and 86% debt, talking about austerity is like eating a box of cakes and calling it “diet”.
The tax burden in this period has been raised throughout the EU (with honorable exceptions, such as Ireland) with an average tax wedge of 45% for workers and 40% on companies.
The United States, at the peak of the crisis, spent 43% of GDP (the EU, 50%) and dropped it to 34%, and that with 21% of the budget in 2009 dedicated to defense.
The EU has been a Keynesian stimulus machine before, through and after the crisis.
1) A massive stimulus in 2008 in a “growth and employment plan”. A stimulus of 1.5% of GDP to create “millions of jobs in infrastructure, civil works, interconnections and strategic sectors”. 4.5 million jobs were destroyed and the deficit nearly doubled.
Between 2001 and 2008, money supply in the euro-zone doubled.
2) Two massive sovereign bond repurchase programs with Trichet as ECB President, interest rates down from 4.25% to 1% since 2008. Poor Trichet. Trichet purchased more than 115 billion euros in sovereign bonds.
3) An additional mega stimulus from the ECB, in addition to the TLTRO liquidity programs with Draghi, which has taken sovereign bonds to the lowest yields in history and purchased almost 20% of the total debt of some major states.
The problem of the European Union has never been a lack of stimuli, but an excess of them.
As government expenditure and unproductive investments multiplied, overcapacity remains at levels of 20% and the constant errors of interventionism leave the euro-zone after the biggest monetary experiment in its history with the same high tax wedge and obstacles to the productive sectors.
The end of the ECB QE leaves the euro-zone in a weaker position than it was in 2011. Because fiscal space has been exhausted and the ECB, with its balance sheet at 41% of the euro-zone GDP and ultra-low interest rates, has also exhausted its monetary tools.
The end of QE does not just show the failure of the ECB’s policy. It highlights the failure of governments’ economic policies.
Governments should implement growth-oriented reforms lowering taxes and attracting capital. Many will not. Most will likely decide, again, that they need to spend more. Fail, repeat.
-------------------------------------------------
