Improved approximation algorithms for low-density instances of the Minimum Entropy Set Cover Problem
نویسندگان
چکیده
We study the approximability of instances of the minimum entropy set cover problem, parameterized by the average frequency of a random element in the covering sets. We analyze an algorithm combining a greedy approach with another one biased towards large sets. The algorithm is controled by the percentage of elements to which we apply the biased approach. The optimal parameter choice has a phase transition around average density e and leads to improved approximation guarantees when average element frequency is less than e.
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ورودعنوان ژورنال:
- Inf. Process. Lett.
دوره 114 شماره
صفحات -
تاریخ انتشار 2014