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Pardalos and Rodgers ([1]) have proposed a test problem generator for
Unconstrained Quadratic Binary Programming (UQBP). Their routine generates symmetric integer matrices and has several parameters to control the characteristics of the problem,
namely:
 | n - The number of variables ; |
 | d - The density, i.e. the probability that a nonzero will occur for any
off-diagonal coefficient (qij); |
 | c- - The lower bound of the
diagonal coefficients (qii); |
 | c+ - The upper bound of the
diagonal coefficients (qii); |
 | q- - The lower bound of the
off-diagonal coefficients (qij); |
 | q+ - The upper bound of the
off-diagonal coefficients (qij); |
 | s - A seed to initialize the random number
generator; |
 | qii~discrete uniform(c-,c+),i=1,...,n; |
 | qij=qji~discrete uniform(q-,q+),1£i<j£n. |
The expected degree of each UBQP instance is the
expected number of quadratic nonzeros per variable. Therefore, the set of
Pardalos problems have a fixed expected degree, i.e. (n-1)d.
[1] - P. Pardalos and G. P. Rodgers, (1990), ''Computational aspects of a branch and bound algorithm for quadratic 0-1 programming'',
Computing 45 131-144. |