10.00 am, Tuesday April 12th, 2005
M345 (Building 28)
ON HORSE RACING, STOCK MARKETS, AND BANKRUPTCY
Ravi Phatarfod
School of Mathematical Sciences, Monash University
The talk DOES NOT purport to show how gambling on horse races
and playing the stock market can lead to bankruptcy. Rather, it is
concerned with common elements in the three activities--horse races
( gambling in general ), stock market , and operation of a commercial
company. The common element is : What is the fraction f of the
capital available at any time should one reinvest.? In the talk we
derive the optimal and critical fractions. We show that if the fraction
invested is greater than the critical one, ruin or bankruptcy is
certain. On the other hand, if the fraction of capital invested is less
than
the critical value, there is a mathematical guarantee that the investor
will
not be ruined. The optimal fraction is called the Kelly fraction.
It is the one which maximizes the expected exponential rate of increase
of the capital.
The talk uses very elementary mathematics--there is just one integral
and two derivatives. So, most of the staff and students should not have
too much difficulty in understanding the major part of the talk.
Convenor:Kais Hamza