Volume 37 - Issue 2 - December 2012

The Cauchy-Frullani integral formula extended to double integrals
   Brita Jung
   pp. 8388
In this note we study the development of the integral formula commonly known as the Cauchy-Frullani integral. It is then shown how a similar formula can be obtained for a double integral, subject to some conditions.

How Euler found the eccentricity of planetary orbits
   Thomas J. Osler, Jasen Andrew Scaramazza
   pp. 8996
Euler discovered an interesting method for astronomers to calculate the eccentricity of a celestial body in an elliptical orbit. We describe the mathematics behind Euler's method and show how it can be used by astronomical observers.

On the statistical independence of primes
   Kais Hamza, Fima Klebaner
   pp. 97105
We characterise probability measures on the set of integers under which the events of being divisible by different prime numbers are independent. Classical identities, such as the Euler product representation, can then easily be obtained by probabilistic means.

Binomial prediction using the frequent outcome approach
   B. O'Neill
   pp. 106121
Within the context of the binomial model, we analyse sequences of values that are almost-uniform and we discuss a prediction method called the frequent outcome approach, in which the outcome that has occurred the most in the observed trials is the most likely to occur again. Using this prediction method we derive probability statements for the prior probability of correct prediction, conditional on the underlying parameter value in the binomial model. We show that this prediction method converges to a level of accuracy that is equivalent to ideal prediction based on knowledge of the model parameter.

The duplication formula derived from the normal distribution
   Rasul A. Khan
   pp. 122124
The Legendre duplication formula for the gamma function is derived from the normal distribution. Its connection with the binomial distribution is also discussed. A classical integral formula in terms of gamma functions is obtained as a byproduct of the normal derivation.

The smallest upper bound for the pth absolute central moment of a
   class of random variables
   M. Egozcue, L. F. García, W.-K. Wong, R. Zitikis
   pp. 125131
We establish the smallest upper bound for the pth absolute central moment over the class of all random variables with values in a compact interval. Numerical values of the bound are calculated for the first ten integer values of p, and its asymptotic behaviour derived when p tends to infinity. In addition, we establish an analogous bound in the case of all symmetric random variables with values in a compact interval. Such results play a role in a number of areas including actuarial science, economics, finance, operations research, and reliability.

Kelly gambling with the stock market and banks
   Ravi Phatarfod
   pp. 132140
In this paper we consider the relative merits of putting money in a bank with a fixed compound interest as against investing it in an investment fund with exposure to the stock market. We show that if the fund manager adopts the Kelly gambling criterion, then there is an upper bound to the volatility of this fund beyond which investing in it is not as profitable as putting money in a bank. We assume a variety of distributions for the random change in the yearly capital value of the investment.

On individual neutrality and collective decision making
   Mu Zhu, Shangsi Wang, Lu Xin
   pp. 141146
We derive a simple mathematical `theory' to show that two decision-making entities can work better together only if at least one of them is occasionally willing to stay neutral. This provides a mathematical `justification' for an age-old cliché among marriage counselors.

Letter to the Editor: New exposition of Gauss' final justification of least
   Oscar Sheynin
   pp. 147148
Letter to the Editor: Poisson and statistics
   Oscar Sheynin
   pp. 149150
Letter to the Editor: Three tangent circles' incircle
   Nelson M. Blachman
   pp. 151153
Index to Volume 37
   p. 154