# Use of Kemeny median in the algorithm of forming recommendation

## DOI:

https://doi.org/10.20535/SRIT.2308-8893.2020.4.05## Keywords:

recommender system, consensus ranking, Kemeny median## Abstract

The relevant nowadays question of development of the algorithmic support of recommender systems is considered. The article is devoted to the solution of the problem of forming recommendations to new users, which is based on the ideas of transition from the matrix "user-object" to the ranking of objects and the formation of recommendations to the user of the active cluster based on the construction of the resulting ranking, which is a Kemeny median on a set of rankings. The choice of Kemeny median as the resulting ranking and the choice of algorithm for its construction are justified. To reduce the complexity of calculations, it is suggested to perform aggregation of information and to use it in forming of ranking recommendations, which are based on a set of "generalized experts" for this cluster. The efficiency of the developed algorithmic support was studied and the results and recommendations were given.

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