Optimal Monte Carlo integration with fixed relative precision

We consider Monte Carlo algorithms for computing an integral @[email protected][email protected] which is positive but can be arbitrarily close to 0. It is assumed that we can generate a sequence X"n of uniformly bounded random variables with expectation @q. Estimator @[email protected][email protected]@?(X"1,X"2,...,X"N) is called an (@e,@a)-approximation if it has fixed relative precision @e at a given level of confidence [email protected], that is it satisfies P(|@[email protected][email protected]|@[email protected]@q)>[email protected] for all problem instances. Such an estimator exists only if we allow the sample size N to be random and adaptively chosen. We propose an (@e,@a)-approximation for which the cost, that is the expected number of samples, satisfies [email protected]^-^1/(@[email protected]^2) for @e->0 and @a->0. The main tool in the analysis is a new exponential inequality for randomly stopped sums. We also derive a lower bound on the worst case complexity of the (@e,@a)-approximation. This bound behaves as [email protected]^-^1/(@[email protected]^2). Thus the worst case efficiency of our algorithm, understood as the ratio of the lower bound to the expected sample size EN, approaches 1 if @e->0 and @a->0. An L^2 analogue is to find @[email protected]? such that E(@[email protected][email protected])^[email protected][email protected]^[email protected]^2. We derive an algorithm with the expected cost EN~1/(@[email protected]^2) for @e->0. To this end, we prove an inequality for the mean square error of randomly stopped sums. A corresponding lower bound also behaves as 1/(@[email protected]^2). The worst case efficiency of our algorithm, in the L^2 sense, approaches 1 if @e->0.

[1]  Søren Asmussen,et al.  Ruin probabilities , 2001, Advanced series on statistical science and applied probability.

[2]  P. Pokarowski,et al.  Fixed Precision MCMC Estimation by Median of Products of Averages , 2009, Journal of Applied Probability.

[3]  G. Lorden On Excess Over the Boundary , 1970 .

[4]  Wojciech Niemiro,et al.  Rigorous confidence bounds for MCMC under a geometric drift condition , 2009, J. Complex..

[5]  B. Epstein Estimates of Bounded Relative Error for the Mean Life of an Exponential Distribution , 1961 .

[6]  Joseph T. Chang Inequalities for the Overshoot , 1994 .

[7]  H. Teicher,et al.  Probability theory: Independence, interchangeability, martingales , 1978 .

[8]  V. Bentkus On Hoeffding’s inequalities , 2004, math/0410159.

[9]  Michael Luby,et al.  An Optimal Approximation Algorithm for Bayesian Inference , 1997, Artif. Intell..

[10]  P. Pokarowski,et al.  Tail events of some nonhomogeneous Markov chains , 1995 .

[11]  P ? ? ? ? ? ? ? % ? ? ? ? , 1991 .

[12]  Daniel Egloff,et al.  QUANTILE ESTIMATION WITH ADAPTIVE IMPORTANCE SAMPLING , 2010, 1002.4946.

[13]  Ronald L. Wasserstein,et al.  Monte Carlo: Concepts, Algorithms, and Applications , 1997 .

[14]  Peter W. Glynn,et al.  Efficient suboptimal rare-event simulation , 2007, 2007 Winter Simulation Conference.

[15]  Peter Mathé Numerical integration using V -uniformly ergodic Markov chains , 2004 .

[16]  W. Hoeffding Probability Inequalities for sums of Bounded Random Variables , 1963 .

[17]  Leslie G. Valiant,et al.  Random Generation of Combinatorial Structures from a Uniform Distribution , 1986, Theor. Comput. Sci..

[18]  Man-Suk Oh,et al.  Adaptive importance sampling in monte carlo integration , 1992 .

[19]  Peter W. Glynn,et al.  Stochastic Simulation: Algorithms and Analysis , 2007 .

[20]  Jian Cheng,et al.  Sampling algorithms for estimating the mean of bounded random variables , 2001, Comput. Stat..

[21]  H. Robbins,et al.  ON THE ASYMPTOTIC THEORY OF FIXED-WIDTH SEQUENTIAL CONFIDENCE INTERVALS FOR THE MEAN. , 1965 .

[22]  Yaacob Ibrahim An Adaptive Importance Sampling Strategy , 1991 .

[23]  Lawrence D. Brown,et al.  Information Inequalities for the Bayes Risk , 1990 .

[24]  R. Serfling,et al.  Asymptotic Theory of Sequential Fixed-Width Confidence Interval Procedures , 1976 .

[25]  C. Cornell,et al.  Adaptive Importance Sampling , 1990 .

[26]  L. Gajek On the Minimax Value in the Scale Model with Truncated Data , 1988 .

[27]  Jian Cheng,et al.  AIS-BN: An Adaptive Importance Sampling Algorithm for Evidential Reasoning in Large Bayesian Networks , 2000, J. Artif. Intell. Res..

[28]  Daniel Rudolf,et al.  Explicit error bounds for lazy reversible Markov chain Monte Carlo , 2008, J. Complex..

[29]  Richard M. Karp,et al.  Monte-Carlo algorithms for the planar multiterminal network reliability problem , 1985, J. Complex..

[30]  M. A. Girshick,et al.  Estimates of Bounded Relative Error in Particle Counting , 1955 .

[31]  A. Nádas An Extension of a Theorem of Chow and Robbins on Sequential Confidence Intervals for the Mean , 1969 .

[32]  Wojciech Niemiro,et al.  Nonasymptotic Bounds on the Mean Square Error for MCMC Estimates via Renewal Techniques , 2011, 1101.5837.

[33]  Peter W. Glynn,et al.  Asymptotic robustness of estimators in rare-event simulation , 2007, TOMC.

[34]  Wojciech Niemiro,et al.  (ε - α ) - MCMC - approximation under drift condition , 2006 .

[35]  Jian Cheng,et al.  Confidence Inference in Bayesian Networks , 2001, UAI.

[36]  K. Latuszy'nski,et al.  Nonasymptotic bounds on the estimation error of MCMC algorithms , 2011, 1106.4739.

[37]  Sumit Roy,et al.  Adaptive Importance Sampling , 1993, IEEE J. Sel. Areas Commun..

[38]  Gerardo Rubino,et al.  Rare Event Simulation using Monte Carlo Methods , 2009 .

[39]  G. Simons Great Expectations: Theory of Optimal Stopping , 1973 .

[40]  Michel Loève,et al.  Probability Theory I , 1977 .

[41]  Erich Novak,et al.  Simple Monte Carlo and the Metropolis algorithm , 2007, J. Complex..

[42]  C. Bucher Adaptive sampling — an iterative fast Monte Carlo procedure , 1988 .

[43]  Yun Bae Kim,et al.  Nonparametric adaptive importance sampling for rare event simulation , 2000, 2000 Winter Simulation Conference Proceedings (Cat. No.00CH37165).

[44]  Reuven Y. Rubinstein,et al.  Steady State Rare Events Simulation in Queueing Models and its Complexity Properties , 1994 .

[45]  D. Siegmund Sequential Analysis: Tests and Confidence Intervals , 1985 .

[46]  Richard M. Karp,et al.  An Optimal Algorithm for Monte Carlo Estimation , 2000, SIAM J. Comput..

[47]  Dirk P. Kroese,et al.  Improved algorithms for rare event simulation with heavy tails , 2006, Advances in Applied Probability.