On Allocating Limited Sampling Resources Using a Learning Automata-based Solution to the Fractional Knapsack Problem

In this paper, we consider the problem of allocating limited sampling resources in a “real-time” manner with the purpose of estimating multiple binomial proportions. This is the scenario encountered when evaluating multiple web sites by accessing a limited number of web pages, and the proportions of interest are the fraction of each web site that is successfully validated by an HTML validator [11]. Our novel solution is based on mapping the problem onto the so-called nonlinear fractional knapsack problem with separable and concave criterion functions [3], which, in turn, is solved using a Team of deterministic Learning Automata (LA). To render the problem even more meaningful, since the binomial proportions are unknown and must be sampled, we particularly consider the scenario when the target criterion functions are stochastic with unknown distributions. Using the general LA paradigm, our scheme improves a current solution in an online manner, through a series of informed guesses which move towards the optimal solution. At the heart of our scheme, a team of deterministic LA performs a controlled random walk on a discretized solution space. Comprehensive experimental results demonstrate that the discretization resolution determines the precision of our scheme, and that for a given precision, the current resource allocation solution is consistently improved, until a near-optimal solution is found – even for periodically switching environments. Thus, our scheme, while being novel to the entire field of LA, also efficiently handles a class of resource allocation problems previously not addressed

[1]  E. Steinberg,et al.  A Preference Order Dynamic Program for a Knapsack Problem with Stochastic Rewards , 1979 .

[2]  Jan Vondrák,et al.  Approximating the stochastic knapsack problem: the benefit of adaptivity , 2004, 45th Annual IEEE Symposium on Foundations of Computer Science.

[3]  M. A. L. Thathachar,et al.  Networks of Learning Automata , 2004 .

[4]  Xiaoming Zeng EVALUATION AND ENHANCEMENT OF WEB CONTENT ACCESSIBILITY FOR PERSONS WITH DISABILITIES , 2004 .

[5]  M. Thathachar,et al.  Networks of Learning Automata: Techniques for Online Stochastic Optimization , 2003 .

[6]  B. John Oommen,et al.  Stochastic learning-based weak estimation of multinomial random variables and its applications to pattern recognition in non-stationary environments , 2006, Pattern Recognit..

[7]  Toshihide Ibaraki,et al.  Fractional knapsack problems , 1977, Math. Program..

[8]  M. L. Tsetlin,et al.  Automaton theory and modeling of biological systems , 1973 .

[9]  Kumpati S. Narendra,et al.  Learning automata - an introduction , 1989 .

[10]  B. John Oommen,et al.  Stochastic searching on the line and its applications to parameter learning in nonlinear optimization , 1997, IEEE Trans. Syst. Man Cybern. Part B.

[11]  Bennett Fox,et al.  Discrete Optimization Via Marginal Analysis , 1966 .

[12]  G. K. Bhattacharyya,et al.  Statistical Concepts And Methods , 1978 .

[13]  Bala Shetty,et al.  The nonlinear knapsack problem - algorithms and applications , 2002, Eur. J. Oper. Res..

[14]  Keith W. Ross,et al.  The stochastic knapsack problem , 1989, IEEE Trans. Commun..