PHOTO: Richard Drew/AP Photo
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30 April 2008—Taiwanese computer scientists have
developed a genetic algorithm—one that evolves to
improve its performance—that can predict the impending
demise or distress of publicly traded companies. Its
creator say it outdoes commonly used financial
algorithms at picking the probability of troubles from
bankruptcy, check bouncing, takeovers, bank runs,
negative net book value, and other financial woes. In
tests on publicly traded Taiwanese companies, it spotted
flailing firms with 90 percent accuracy two years before
they flamed out.
Carlos A. Coello Coello, an expert on such algorithms
with the Research and Advanced Studies Centre of the
National Polytechnic Institute, in Mexico City, who was
not involved in the research, says that for prediction
accuracy, 90 percent is “to say the least, remarkable.”
According to the software's coinventor Ping-Chen Lin,
an associate professor at the Department of Finance and
Institute of Finance and Information at the National
Kaohsiung University of Applied Sciences, in Taiwan, the
secret to the predictive system's success is the
combination of the genetic algorithm's ability to evolve
to weigh the value of a set of variables, and the mixing
of three types of prediction procedures.
For the period from 1993 to 2004, Lin and her research
partner, the late Jiah-Shing Chen, who was a professor
in the Department of Information Management at Taiwan's
National Central University, in Jhongli City, retrieved
the pertinent statistics of 537 domestic companies
listed either in the Taiwan Stock Exchange (TSE) or
GreTai Securities Market. They then used three-fourths
of the companies to train the program and applied the
results to the other fourth.
The company statistics used in the algorithm consisted
of 39 variables—including net sales, total assets,
market value of equity, sales-growth rate, return on
total assets, current ratio, and leverage—indicating
the financial situation of companies. Lin and Chen then
used a genetic algorithm to obtain different weights for
each according to how well they correlated with the
companies' final financial situations.
“Imagine [how] a chromosome having 39 genes evolves,”
says Lin. “Natural evolution has a tendency to optimize
the situation. Its application in financial analysis can
reduce irrelevant variables.”
Once the genetic algorithm has selected and weighed
the variables, they are fed into a second stage of the
program, a hybrid prediction program. It integrates the
advantages of three different prediction methods:
discriminate analysis, logistic regression, and neural
networks. The first two are traditional statistics
methods, explains Lin. The last is based on an
artificial neural network—an interconnected collection
of software constructs that mimic some of the properties
of brain cells.
“The results show that the combination of three models
leads to the highest accuracy rate,” says Lin. Indeed,
the mean forecasting accuracy of Lin's predicting system
for eight financial quarters prior to a company's
failure is roughly 90 percent.
Lin says this hybrid approach could help fund
managers, stock investors, banks, and others avoid risk.
Taking the loan departments of banks in Taiwan as an
example, Lin says that a final decision to lend money to
a company is sometimes made based on past experience and
the results of existing programming software tools.
Those tools are designed using traditional statistical
methods and cover certain indicators, which might be
less suitable than those selected by the genetic
algorithm, she says.
The algorithm was developed and tested using only
Taiwanese companies, but a similar predicting system can
be easily constructed for companies in other countries
“as long as researchers select variables appropriately
and have enough target companies to conduct
experiments,” Lin says.
Lin reported the results of the system in the March
2008 issue of the International Journal of
Electronic Finance. The same month, she
published a Chinese-language book (in Taiwan) further
detailing the research. Now Lin's team is working on
improving the prediction system in a bid to forecast
whether a company will default on a loan. She says banks
can adjust the terms and conditions based on the
forecast to minimize the risk induced by nonperforming loans.