Article of interest

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Guenther Ossimitz
Junior Member
Posts: 17
Joined: Fri Mar 29, 2002 3:39 am

Article of interest

Post by Guenther Ossimitz »

John Sterman wrote:

> Solving the commons problem, though crucial, is far from sufficient to
> ensure critical resources will be used appropriately. Erling suggests some
> remedies for the misperceptions of feedback that may lead individuals and
> society to destroy resources even when there is every incentive to harvest
> them sustainably.

The findings of Erling Moxnes are no surprise for me. Experiments of the
German cognitive psychologist Dietrich Doerner lead to similar results.
Doerner e.g. let probands try to keep the temperature of a simulated cooling
house (the "K|hlhaus-Experiment") constant. The model hardly could be simpler:
it had just one stock variable and only one wheel for the probands to steer:
more cooling or less cooling.
The mere presence of a considerable delay in the reaction of the temperature
to steering inputs led by a considerable number of probands to a total
overshoot
behavior. I suspect that the simple existence of considerable time-delays make
it very difficult for many people to behave appropriately. This would also
apply
to the fishing model, where you have to reduce the amount of fishing at a
rather
early stage of the model developement in order to prevent the disaster.

G. Ossimitz


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University of Klagenfurt
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Phone: +43/463-2700-437 Fax:+43/463-2700-427
mail:
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JESUS IS LORD - YESTERDAY, TODAY AND FOREVER!
John Sterman
Senior Member
Posts: 117
Joined: Fri Mar 29, 2002 3:39 am

Article of interest

Post by John Sterman »

I highly recommend that people read the article by Erling Moxnes entitled
"Not Only the Tragedy of the Commons: Misperceptions of Bioeconomics"
which appeared in Management Science, 44(9), Sept. 98 (1234-1248).

Erling conducted a lab experiment with a simulated fishery in which the
decision makers (mostly professionals in the Norwegian fishing industry)
managed a stock of fish and decided how many boats to buy and how intensely
to fish.

As you might expect, people tended to buy too many boats and harvest too
many fish. This is not surprising since we all know that a common resource
like fish is subject to destruction through the .tragedy of the commons.

What is surprising is that Erling eliminated the common resource problem in
his experiment by giving each subject in the experiment complete and
perfect property rights. They owned the fish completely, and there was no
migration of fish away from their private fjord.

Therefore, the overfishing behavior observed cannot be explained by the
commons problem. Erling shows that overfishing arises from
mispercepctions of feedback - specifically, the dynamic complexity of the
fishery management system was not captured in the mental models of the
subjects (remember, most were experts in the real fishing industry). That
is, as shown in prior experiments, people are unable to manage well in
dynamically complex systems.

I believe this study is highly significant. Most discussions of commons,
from fisheries to highways to water to the ozone layer to the global
climate, are dominated by the commons problem. Indeed, the commons problem
is serious, and must be addressed if these resources are to avoid
overexploitation and collapse. However, most analysis also assumes that
if the commons problem were solved, then resources usage would rapidly
approach the socially optimal rate and lead to sustainable exploitation.
Erlings results show this optimistic view is unlikely to be correct.
Solving the commons problem, though crucial, is far from sufficient to
ensure critical resources will be used appropriately. Erling suggests some
remedies for the misperceptions of feedback that may lead individuals and
society to destroy resources even when there is every incentive to harvest
them sustainably.


John Sterman
J. Spencer Standish Professor of Management
Director, MIT System Dynamics Group
MIT Sloan School of Management
E53-351
30 Wadsworth Street
Cambridge, MA 02142
617/253-1951 (voice); 617/258-7579 (fax), jsterman@mit.edu
http://web.mit.edu/jsterman/www
Moxnes Erling
Junior Member
Posts: 9
Joined: Fri Mar 29, 2002 3:39 am

Article of interest

Post by Moxnes Erling »

Guenther Ossimitz wrote the following concerning my article in Managment
Science:

"The findings of Erling Moxnes are no surprise for me. Experiments of the
German cognitive psychologist Dietrich Doerner lead to similar results.
Doerner e.g. let probands try to keep the temperature of a simulated cooling
house (the "K|hlhaus-Experiment") constant. The model hardly could be
simpler: it had just one stock variable and only one wheel for the
probands to steer: more cooling or less cooling. The mere presence of a
considerable delay in the reaction of the temperature to steering inputs
led by a considerable number of probands to a total overshoot behavior.
I suspect that the simple existence of considerable time-delays make it
very difficult for many people to behave appropriately. This would also
apply to the fishing model..."

In light of the emerging literature on misperception of feedback by
Doerner, Sterman and others referred to in the article, mismanagement is
no big surprise anymore. What might be surprising, however, is how
simple the structures that lead to mismanagement can be. This leads me
to believe that it is worth while to focus on the crux of the matter,
i.e. very simplified models. If the relationship between structure and
behaviour and the nature of "optimal" policies for these simple
structures are not comprehended, it is difficult to imagine that
decision makers can get it right in more complex settings, transfer
insights from one setting to another (diffusion) etc.

The simple structures involved also bring forth another interesting
point. One does not need "a paradigm shift" in terms of methodology to
solve dynamic problems. The simple basic model is adequately described
by conventional methods and insights. The study calls for better
teaching and more efficient diffusion of information.

Erling Moxnes
From: Moxnes Erling <
Erling.Moxnes@snf.no>
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