Queueing Systems

, Volume 4, Issue 2, pp 115–135 | Cite as

Approximating probability densities on the positive half-line

  • Michael L. Wenocur
Contributed Papers


A variety of methods for approximating probability density functions on the positive half-line are presented and discussed. In particular, the method of moments and orthogonal expansion methods are studied. We give a new, computational proof that continuous probability densities vanishing at ∞ can be uniformly approximated by generalized hyper-exponential densities. The same denseness property is also shown to hold for families of densities expressible as sums of Erlang densitieswith common fixed rate parameter.


adaptive approximation denseness generalized hyperexponential hypo-exponential Laguerre transforms Laplace transforms linear combinations of Erlang distributions method of moments orthogonal expansions rational approximation 


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Copyright information

© J.C. Baltzer A.G. Scientific Publishing Company 1989

Authors and Affiliations

  • Michael L. Wenocur
    • 1
  1. 1.Ford Aerospace CorporationMail Stop X-38, San JoseUSA

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