Subprime Winners: Rational Herds & Decision Researchers

US capital and derivatives markets in mid-2008 provide a real-time laboratory for behavioural finance analysts who want to understand the madness and wisdom of crowds.  The past week’s case studies include the implosion of the US bank IndyMac and the market volatility triggered by fears that Fannie Mae & Freddie Mac are highly exposed to liquidity risk.

As financial reporter Michael S. Rosenwald notes in The New York Times, these recent events appear to fit the behavioural finance hypothesis that individual investors who make fear-driven and risk-averse decisions can trigger pricing shifts as an aggregate rational herd.  Guillermo A. Calvo and Enrique Mendoza found in a 1997 paper that globalisation counteracts the emergence of rumour markets based on imperfect information and country-specific knowledge, although not in emerging markets due to uncertainties.

However the recent events have different conditions that set delimits on Calvo and Mendoza’s model: the United States is the epicentre of the bear market triggered by the 2007 subprime crisis, Fannie Mae and Freddie Mac have psychological primacy as major financial institutions with US Federal Government backing, and investment media firms such as Bloomberg and CNBC use globalisation to create de facto rumour markets amongst day-traders and others.

Readers interested in rational herds should also check out Christopher P. Chamley’s book Rational Herds: Economic Models of Social Learning (Cambridge University Press, Cambridge UK, 2004), excerpt here.

Decision researchers are the other early winners of the 2007 subprime crisis, due to the failure of many quantitative models to predict the Black Swan event.  Rosenwald mentions Harvard University’s new Bio-Behavioral Laboratory for Decision Science which conducts ‘conducts research on the mechanisms through which emotional and social factors influence judgment and decision making.’  He also refers to the Oregon-based nonprofit group Decision Research.  An Australian-based counterpart might be the Capital Markets CRC, an R&D consortia that focuses on ‘new technologies and improvements in market design’.

Investment analysts still have divergent opinions on recent events.  However the research agenda above prompts several new questions:  What happens to rational herds and rumour markets when bio-behavioural methods of decision-making are no longer ‘imperfect information’ but are widely understood and integrated into investment choices?  How will markets be redesigned to cope with this eventuality, and who will take on this responsibility?  What new financial instruments, markets and products will emerge generativity?

Bryan Burrough on Bear Stearns’ Demise: A Dark Possibility

Bryan Burrough is legendary in M&A circles for co-writing Barbarians at the Gate (Harper & Row, New York, 1990) with John Helyar, the cautionary tale of RJR Nabisco’s leveraged buyout and the winner’s curse faced by deal-maker Henry Kravis.

Burrough’s latest investigation for Vanity Fair contends that short sellers used CNBC and other media outlets to spread rumours that destabilised Bear Stearns and sparked a liquidity run on the investment bank’s capital.  Burrough’s thesis has sparked debate that overshadows his investigation’s strengths: a strong narrative and character portraits, new details of the negotiations with JPMorgan Chase and the Federal Reserve, and a cause-effect arc that shifts from CNBC’s internal editorial debate to the effects its coverage has on the marketplace and the subjective perceptions of individual investors and senior decision-makers.

In the absence of a ‘secret team’ or a ‘smoking gun’ how could Burrough’s thesis be tested?

Theoretically, Burrough’s hypothesis fits with: (1) a broad pattern over two decades of how media outlets respond to media vectors, systemic crises and geostrategic surprises; (2) the causal loop dynamics and leverage points in systems modelling; (3) the impact that effective agitative propaganda can have in psychological operations; and (4) the complex dynamics and ‘strange loops’ in rumour markets (behavioural finance) and rumour panics (sociology), notably ‘information cascade’ effects on ‘rational herds’.

This is likely a ‘correlation-not-cause’ error although it does suggest a dark possibility for strategic intervention in financial markets: could this illustrative/theoretical knowledge be codified to create an institutional capability, deployed operantly, and which uses investor fears of bubbles, crashes, manias and various risk types as a pretext for misdirection?  Behavioural finance views on groups and panics, and George Soros‘ currency speculation against the Bank of England’s pound on Black Wednesday suggest the potential and trigger conditions may lie in the global currency/forex markets (using stochastic models like Markov Chain Monte Carlo for dynamic leverage in hedge funds) and money markets (using tactical asset allocation).  If possible, this capability could also create second- and third-order effects for regulators, the global financial system and macroeconomic structures, and volatility in interconnected markets, which may actually be more dynamic and resilient than this initial sketch indicates.

To meet quantitative standards and validate Burrough’s hypothesis a significant forensic and data analytics capability with error estimates would also be required.  ‘Strong’ proof may not be possible: Burrough’s hypothesis is probably an unsolvable ‘mystery’ rather than a solvable ‘puzzle’ (a distinction by intelligence expert Gregory Treverton that The New Yorker‘s Malcolm Gladwell later popularised).

Ironically, several CNBC analysts have already decided: they used parts of Burrough’s hypothesis to explain the subsequent short-selling driven volatility of Fannie Mae and Freddie Mac‘s stock prices in mid-July 2008.