Almost every aspect of the current mortgage mess can be traced to Greenspan.
Does anyone know any good sources for economic systems analysis? (I’m talking systems analysis applied to economics, not analysis of economic systems)
In control theory, the outputs of a system is fed via a feedback loop into one or more of its inputs in order to control system behavior. For instance, an aircraft altitude control system would measure altitude and feed surface controls to climb or descend in order to keep altitude steady. One of the principles of control theory is that resonances normally exist in an untuned system. In the example, if there is a delay between the climb/descend command and the actual climb or descent of the aircraft, you end up with a porpoising effect caused by overcorrections.
In free-market economics, the system feedback is provided by money supply. As investments soar during a growth spurt, the amount of money available from banks drops, interest rates rise to reflect a shifting supply/demand point for loans, and the attractiveness of the investment decreases, stalling the bubble. The phase relationship of interest rates to economic growth sets up the porpoising resonance known as the business cycle. (Simplification, but the principles hold true)
One mistake in control theory is to try to control the system too tightly. In the airplane example, this would be illustrated by a system which pitches up sharply to climb, then when passing through altitude, immediately pitches down to descend. Looking at an altitude indicator, you might see a system which is holding very tightly to its altitude profile, but stepping away from that one parameter, you would see an aircraft pitching violently up and down in order to keep the one parameter steady. This is a system in resonance, and it will continue in this mode until the resonance becomes too violent to counteract, at that point, the system “blows up” (figuratively and literally).
A properly designed system is analyzed for all physical forces and actions and “tuned” to remove resonances. It allows some looseness in control as a trade off for stability.
Taking this back to the economic world, the proper role of the Fed (assuming you see no value in a natural business cycle’s purging of inefficient businesses), is to tune the economy so that the business cycle is dampened out and the economy can grow steadily. Two ways of doing this:
In a proper tuning approach, you would try to sync the phases of the money supply and business activity so that money supply started dwindling sooner in the growth phase. This reduces, but does not eliminate the business cycle resonance, and creates a stable economy (not necessarily growing).
In a tight control approach, you would jerk the controls up and down in response to the week-by-week behavior of the economy, not looking at long term stability, but only trying to hold one specific parameter in place.
I believe we are in a tight control paradigm, and while the economy may seem pretty steady (though a little jittery) the controls are in a violent resonance that seems to be growing, and seems to have been growing since the late 90’s.
Now the question:
Did Greenspan know so little about control theory that he allowed himself to be sucked into a tight control approach in order to maintain economic activity?
Or,
Did he analyze all the interactions and intentionally start a slow growing control resonance, knowing that it would be beyond control by the time he left the Fed, and that it would go critical long enough after he left to avoid serious blame?
Or to put it simply: Did Rand’s “Undertaker” cast himself as D’Anconia?