This paper discusses the modelling and control of pension funds. A continuous-time stochastic pension fund model is proposed in which there are n risky assets plus the risk-free asset as well as randomness in the level of benefit outgo. We consider Markov control strategies which optimise over the contribution rate and over the range of possible asset-allocation strategies. For a general (not n...

the first step to quantify crop phenology is precise estimation of the parameters, which affect it. these parameters are mainly temperature and photoperiod. this study was conducted with eight sowing dates to quantify response of stem elongation rate (ser) to temperature and photoperiod in wheat (tajan cultivar). the regression models fitted to ser against temperature were flat, logistic, quadr...

Summary We investigate estimation of a normal mean matrix under the quadratic loss. Improved loss implies improved any linear combination columns First, an unbiased estimate risk is derived and Efron–Morris estimator shown to be minimax. Next, notion superharmonicity for matrix-variate functions introduced have properties analogous those usual superharmonic functions, which may independent inte...

A lower bound for the linear complexity of sequences generated by the quadratic function x2 mod p is given.  1999 Published by Elsevier Science B.V. All rights reserved.

We prove by symmetry properties that the Lagrangian of a free pointmass is a quadratic function of the speed in the non-relativistic case, and that the action of the free point-mass between two spacetime points is the proper time passed in the relativistic case. These well known facts are proved in a mathematically rigorous way with a frame independent treatment based on spacetime models introd...

Let A be a hermitian matrix of order n, and b a known vector n H in C . The problem is to determine which vectors make ^(x) = (x-b) A(x-b) H a maximum or minimum on the unit sphere U = fx : x x = 1} . The problem is reduced to the determination of a finite point set, the spectrum of (A,b). The theory reduces to the usual theory of hermitian forms when b = 0. *J Reproduction in Whole or in Part ...

We construct a finitely presented group G with non-quadratic Dehn function f majorizable by a quadratic function on arbitrary long intervals.

The optimal policy response to a low-probability extreme event is examined. A simple policy problem is solved for a sequence of different loss functions: quadratic, combined quadratic/absolute-deviation, absolute-deviation, combined quadratic/constant, and perfectionist. The paper shows that, under some simplifying assumptions, each of these loss functions puts less weight on a low-probability ...