Why We Should Be Wary of the Confirmation Bias

From the prodigious Matt Ridley writing at the Wall Street Journal,

One of the alarming things about confirmation bias is that it seems to get worse with greater expertise. Lawyers and doctors (but not weather forecasters who get regularly mugged by reality) become more confident in their judgment as they become more senior, requiring less positive evidence to support their views than they need negative evidence to drop them.

The origin of our tendency to confirmation bias is fairly obvious. Our brains were not built to find the truth but to make pragmatic judgments, check them cheaply and win arguments, whether we are in the right or in the wrong.

I find this very relevant, especially the last sentence. Debates at social network sites seem as testament to these.

George Selgin on Nouriel Roubini’s Book and Nouriel Roubini the Insider

Economist George Selgin takes down Nouriel Roubini and Stephen Mihm’s analysis of the US mortgage crisis of 2007-2008 (source: The Independent Institute)

(all bold emphasis mine)

Abstract

Nouriel Roubini and Stephen Mihm rightly castigate the Federal Reserve and other central banks for policies that contributed to the recent worldwide housing boom and bust, but they seriously underestimate the role of the Community Reinvestment Act and the government-sponsored enterprises in facilitating the surge of subprime mortgage loans in the United States. In addition, their proposals to prevent future financial crises rest on errors about the repeal of the Glass-Steagall Act and other matters of economic history.

Article

It takes only three paragraphs for Nouriel Roubini and Stephen Mihm, the authors of Crisis Economics: A Crash Course in the Future of Finance, to tell how Roubini stunned listeners at a September 2006 International Monetary Fund seminar by heralding a “once-in-a-lifetime” housing bust to be followed by a deep, long recession (Roubini and Mihm 2010, 1–2). Yet they may still deserve credit for modesty, for if one devoted Roubini watcher is to be believed, “Dr. Doom” actually predicted no fewer than “48 of the last 4 recessions” (comment on Elfenbein 2009). Some quick fact-checking lends credence to our informant’s otherwise incredible claim by showing that Roubini predicted a serious crash for 2004, then a severe slowdown for 2005, then a global reckoning for 2006, and finally a sharp recession for 2007. After the much-trumpeted crisis at last materialized (though not quite for the reasons Roubini had harped on), he declared that the S&P 500 would sink to 600, that oil would get stuck below $40 a barrel, and that a gold “bubble” was about to do what the housing one had done. To be sure, these things have not yet come to pass, but tomorrow is another day, and to succeed prophets need only mark when they hit and never mark when they miss.

If Roubini’s marksmanship impresses you, you are perhaps bound to hang on every word of Crisis Economics, no matter what any less-than-divine reviewer says about it. If, on the other hand, that marksmanship puts you in mind of the accuracy of a stopped clock, you may hearken to the warning that although the book’s assessment of the causes of the recent great housing boom and bust is for the most part sound and informative, some of its claims are highly misleading, if not simply false. Roubini and Mihm start well enough by dismissing as red herrings various popular diagnoses of the crisis, including the “tired” argument that it was caused by “greed,” with its far-fetched though implicit assumption “that the financiers of 2007 were greedier than the Gordon Gekko’s of a generation ago” (pp. 31–32). They draw attention instead to changes in the structure of incentives “that channeled greed in new and dangerous directions” (p. 32). These changes included government policies aimed at increasing poorer (and riskier) persons’ access to mortgages, the growing moral hazard connected with the “too big to fail” doctrine, and the Federal Reserve’s post-2001 easy-money policy.

Read the rest here

My additional comments on the celebrity guru:

It has been a long curiosity for me why many people seem to adore someone who has had a sordid string of utterly wrong predictions or maintains a poor batting average in predicting events (as Mr. Selgin points out).

Media seem to remember his ‘broken clock’ accurate prediction of 2007, but have been lenient or forgetful or forgiving of his blatant miscalls. As a saying goes, even the broken clock can be right twice a day.

A good example of this was the controversial debate with the legendary investor Jim Rogers where Mr. Roubini said that gold prices won't reach $1,500 to $2,000 which has obviously been proven wrong.

If Mr. Roubini had been a money manager he would have been a mediocre. Except that he isn’t. So wrong calls does not translate to any real or dollar value losses, so he can afford to keep talking.

One reason that makes Mr. Roubini a celebrity is that his themes sells to the consensus or that he provides the public a ‘confirmation bias’ or that his ideas seem to tailor fit with mainstream’s biases.

Recently Mr. Roubini commented

So Karl Marx, it seems, was partly right in arguing that globalization, financial intermediation run amok, and redistribution of income and wealth from labor to capital could lead capitalism to self-destruct (though his view that socialism would be better has proven wrong). Firms are cutting jobs because there is not enough final demand. But cutting jobs reduces labor income, increases inequality and reduces final demand.

Here Mr. Roubini passes the proverbial hot potato blame on the free markets which liberals would gladly rally to and cheer on.

Nevertheless what has sorely been missed in this commentary is that the main source of malignancy can be traced to mostly central banking boom bust policies and other interventionist-welfare-bailout programs, an aspect Mr. Roubini and his ilk chooses to ignore.

Economist Bob Wenzel is right; Mr. Roubini’s real value isn’t his economic expertise but his insider connection. Writes Mr. Wenzel,

The one point I do take away from Roubini's commentary is in the area that he has demonstrated expertise and that is not in the area of economic theory. He is an expert in knowing what insiders are plotting. In the vernacular of the day, he knows what is coming down.

Mr. Roubini seems part of the counsel which help shapes the ‘insider’ philosophy and who provides the ideological cover to promote the 'insider's' interests.

Explaining Popularity In Terms of Predictions: Dr. Nouriel Roubini’s Case

This seems like good news to me. My favourite mainstream Keynesian bear, Nouriel Roubini, appears to have ‘capitulated’. Mr. Roubini, a popular and very well connected economist, has almost always been on the wrong side of the prediction fence, and this seems to be just another of chapter of his string of failed forecasts and eventual turnaround.

Mr. Roubini has turned bullish on the US markets, reports the Bloomberg,

Nouriel Roubini, the economist who predicted the financial crisis, said U.S. stocks may gain in the next few months as company earnings remain resilient.

Adds Thomas Brown of bankstocks.com

What the heck happened to the L-shaped recovery? Roubini’s view is now squarely within the mainstream expectation. Good for him. The facts changed, and so he changed his opinion. Keynes would be pleased.

For me, Mr Roubini exemplifies as one of the bizarre ironies of the marketplace where despite his persistent wrong predictions, Mr. Roubini has remained quite popular with media.

If his strategy has been patterned to a tournament bridge game called “playing for a swing” as Professor Arnold Kling suggests, where “It would appear that Roubini's strategy is to make forecasts that differentiate himself from the consensus forecast. This allows him to be spectacularly right sometimes and spectacularly wrong sometimes. As long as he succeeds in getting everyone to remember the right forecasts more clearly than the wrong ones, he becomes a prophet”, then his success reflects on the public’s poor memory (or survivorship bias).

Google search trends for Mr. Roubini vis-a-vis Dr. Marc Faber

While there may be some truth to this, I am not convinced.

The public seems jaded to the forecasting accuracy by experts.

In relative performance, another (less) popular grizzly bear (but Austrian school leaning bear), Dr Marc Faber, who appears to have consistently been accurate even in predicting short to medium term trends—even the latest divergence between EM and developed economies stocks—has almost trailed Dr. Roubini’s in terms of popularity. (note the difference in search volume index—X axis).

So the explanation of “spectacularly” right or wrong doesn’t seem to suffice.

Instead, I think, Mr. Roubini signifies what the public wants to hear more than the validity of his theories. He personifies the confirmation of many entrenched but flawed beliefs.

Search volume for Austrian versus Keynesian Economics

One would note of an almost similar performance between Dr. Faber and Dr. Roubini’s popularity variance levels—Austrian economics has largely been subordinate in popularity to Keynesian economics during the past years (although this could be changing).

Finally there could be another factor: pessimism bias sells.

In the question and answer portion of this splendid talk on innovation, economist Deirdre McCloskey points out that Paul Ralph Elrich remains quite popular in spite of his ‘spectacularly’ wrong prediction.

Mr. Elrich is known for having lost the famous Simon-Elrich wager- wager that based on the price of 5 metals anchored upon the overblown risks of overpopulation.

Perhaps many are simply more attracted to a pessimistic outlook, whether valid or not, out of the penchant to see or resist a change in the status quo, or based on social signalling (to conform with the consensus outlook or to show intellectual prowess or promote an ideology, e.g. using fear to expand government control)

As Professor Bryan Caplan writes,

David Hume—economist, philosopher, and Adam Smith’s best friend—blamed popular pessimism on our psychology. “The humour of blaming the present, and admiring the past, is strongly rooted in human nature,” he wrote, “and has an influence even on persons endued with the profoundest judgment and most extensive learning.”

Bottom line: The popularity of economic or market forecasters appear grounded mostly on the confirmation bias or giving the public what they want or desire to hear more than the validity of theories or the batting average or the accuracy of predictions.