Stuff Happens
Richard Bookstaber a long time finance
practitioner/risk manager who has worked for Morgan Stanley, Salomon Brothers,
Moore Capital and Bridgewater as well as the Financial Stability Oversight
Council and the Office of Financial Research has written a broad-based attack
on financial economics and the DSGE models now used by most central banks.
Trust me he knows what he is writing about and in the interests of full
disclosure I interacted with him when I worked at Salomon Brothers.
Although not cited he is writing in the
tradition of Nicholas Nassim Taleb (“The Black Swan”) with his fundamental
disagreement with the theoretical underpinnings of financial economics. Simply
put in a world of radical uncertainty we don’t know the underlying probability
distributions of future financial returns and we don’t even know the potential
states of the world needed to calculate a probability distribution. He argues
that modern finance theory is built around top down axioms based on deductive
reasoning where an all knowing representative individual calculates the future
probabilities for all of the known states of the world. And importantly the
future probability distribution is based on historical evidence. Under radical
uncertainty that simply does not work.
Instead he argues for agent based models
built upon inductive reasoning where the actors are “reflexive” in the word
used by George Soros, in that they respond to the actions of others. As much as
economists envy physics, Bookstaber turns the Heisenberg uncertainty principle
on them. Thus while financial theory works in normal times, in a crisis all
bets are off as “stuff happens.”
What Bookstaber would like is to use
agent based models that are used to model automobile traffic and schools of
fish, for example, through the use of complexity theory. All this is fine and
good, but aside from a narrative Bookstaber does not offer up a formal model
for the financial markets. Perhaps he has one, but it is not here. Nevertheless
he offers a road map for future research.
At times Bookstaber’s writing style is
clear and lucid with analogies from literature motion pictures and military
combat. He is a student of “OODA”, observe, orient, decide and act. He is
particularly acute in his discussion of the origins of the financial crisis and
is highly critical of the role played by Goldman Sachs in their failure to
honor a small “novation” request from Bear Stearns, which brought that firm
down. However, at other times his writing is dull and staid
Bookstaber has written an important book
and it should be read by risk managers and policy officials. The old models
failed in 2008, now almost ten years later it is time for new ones.
The full Amazon URL appears at:
https://www.amazon.com/review/R14VHKPZ87FCAC/ref=pe_1098610_137716200_cm_rv_eml_rv0_rv
https://www.amazon.com/review/R14VHKPZ87FCAC/ref=pe_1098610_137716200_cm_rv_eml_rv0_rv
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