Abstract
The problem of finding a maximal subsample in a training sample consisting of the pairs “object-answer” that does not violate monotonicity constraints is considered. It is proved that this problem is NP-hard and that it is equivalent to the problem of finding a maximum independent set in special directed graphs. Practically important cases in which a partial order specified on the set of answers is a complete order or has dimension two are considered in detail. It is shown that the second case is reduced to the maximization of a quadratic convex function on a convex set. For this case, an approximate polynomial algorithm based on linear programming theory is proposed.
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Original Russian Text © R.S. Takhanov, 2010, published in Zhurnal Vychislitel’noi Matematiki i Matematicheskoi Fiziki, 2010, Vol. 50, No. 7, pp. 1327–1333.
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Takhanov, R.S. On the sample monotonization problem. Comput. Math. and Math. Phys. 50, 1260–1266 (2010). https://doi.org/10.1134/S0965542510070146
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DOI: https://doi.org/10.1134/S0965542510070146