A Linear Programming Algorithm for Computing the Stationary Distribution of Semimartingale Reflected Brownian Motion Denis Saure¤ Peter W. Glynny Assaf Zeeviz Columbia University Stanford University Columbia University March 2008 Abstract This paper proposes a linear programming algorithm for computing the stationary distribu- tion of semimartingale reflected Brownian motion (SRBM), which arises as an approximation of certain queueing networks operating in heavy-tra±c. Our algorithm is based on a Basic Adjoint Relationship (BAR) which characterizes the stationary distribution. Approximating the state space with a ¯nite grid of points and using a ¯nite set of \test" functions, the BAR reduces to a set of linear equations that can be solved using standard linear programming techniques. As the set of test functions increases in complexity and the grid becomes ¯ner, the sequence of sta- tionary distribution estimates which arise as solutions to the algorithm converges, in a suitable sense, to the stationary distribution of the SRBM. The algorithm is seen to produce good esti- mates of the stationary moments as well as the entire distribution. Extension to settings with parameter uncertainty, and to Ornstein-Uhlenbeck-type di®usions arising in the many-servers heavy tra±c regime, are discussed as well. Preliminary Draft Copy { Not for Distribution Short Title: Computing the stationary distribution of SRBM Keywords: queueing, di®usion approximations, reflected Brownian motion, Hal¯n-Whitt regime, numerical methods, linear programming. 2008 AMS Subject Classi¯cation (Primary): XXXX - XXXX - XXXX ¤Columbia Graduate School of Business, e-mail:
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