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Data Structures. Universal Hash Functions: Definition and Example. Design and Analysis of Algorithms I. Overview of Universal Hashing. Universal Hash Functions.
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Data Structures Universal Hash Functions: Definition and Example Design and Analysis of Algorithms I
Consider a hash function family , where each hash function of maps elements from a universe to one of buckets. Suppose has the following property: for every bucket and key , a fraction of the hash functions in map to . Is universal? Yes, always. No, never. Maybe yes, maybe no (depends on the ). Only if the hash table is implemented using chaining.