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REAL ZEROS OF ALGEBRAIC POLYNOMIALS WITH STABLE RANDOM COEFFICIENTS

Published online by Cambridge University Press:  01 August 2008

K. FARAHMAND*
Affiliation:
Department of Mathematics, University of Ulster at Jordanstown, Country Antrim, BT37 0QB, United Kingdom (email: [email protected])
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Abstract

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Weconsider a random algebraic polynomial of the form Pn,θ,α(t)=θ0ξ0+θ1ξ1t+⋯+θnξntn, where ξk, k=0,1,2,…,n have identical symmetric stable distribution with index α, 0<α≤2. First, for a general form of θk,αθk we derive the expected number of real zeros of Pn,θ,α(t). We then show that our results can be used for special choices of θk. In particular, we obtain the above expected number of zeros when . The latter generate a polynomial with binomial elements which has recently been of significant interest and has previously been studied only for Gaussian distributed coefficients. We see the effect of α on increasing the expected number of zeros compared with the special case of Gaussian coefficients.

Type
Research Article
Copyright
Copyright © 2008 Australian Mathematical Society

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