On the intersection of independence systems
نویسنده
چکیده
We study the properties of the intersection of independence systems. An independence system (V, I) is a k-system if for all S ⊆ V the ratio of the cardinality of the largest to the smallest maximal independent subset of S is at most k. We show that the intersection of a k1-system and a k2-system is a (k1 + k2)-system. As an application of our results, we show an improved approximation algorithm for stochastic probing with deadlines over k-systems.
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عنوان ژورنال:
- Oper. Res. Lett.
دوره 43 شماره
صفحات -
تاریخ انتشار 2015