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Algorithms

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Think Bayes. Bayesian Statistics Made Simple by Allen B. Downey Download Think Bayes in PDF. Read Think Bayes in HTML. Order Think Bayes from Amazon.com. Read the related blog, Probably Overthinking It. Description Think Bayes is an introduction to Bayesian statistics using computational methods. The premise of this book, and the other books in the Think X series, is that if you know how to program, you can use that skill to learn other topics.

Most books on Bayesian statistics use mathematical notation and present ideas in terms of mathematical concepts like calculus. I think this presentation is easier to understand, at least for people with programming skills. Think Bayes is a Free Book. Other Free Books by Allen Downey are available from Green Tea Press. Download Precompiled copies of the book are available in PDF. Other Free Books by Allen Downey are available from Green Tea Press. Bloom filter. Bloom proposed the technique for applications where the amount of source data would require an impracticably large hash area in memory if "conventional" error-free hashing techniques were applied. He gave the example of a hyphenation algorithm for a dictionary of 500,000 words, out of which 90% follow simple hyphenation rules, but the remaining 10% require expensive disk accesses to retrieve specific hyphenation patterns.

With sufficient core memory, an error-free hash could be used to eliminate all unnecessary disk accesses; on the other hand, with limited core memory, Bloom's technique uses a smaller hash area but still eliminates most unnecessary accesses. For example, a hash area only 15% of the size needed by an ideal error-free hash still eliminates 85% of the disk accesses (Bloom (1970)). More generally, fewer than 10 bits per element are required for a 1% false positive probability, independent of the size or number of elements in the set (Bonomi et al. (2006)). . . . As before. How are bloom filters used in HBase.

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Hexagonal tiling. Text extraction. Natural language. Language. Selection algorithm. The simplest case of a selection algorithm is finding the minimum (or maximum) element by iterating through the list, keeping track of the running minimum – the minimum so far – (or maximum) and can be seen as related to the selection sort. Conversely, the hardest case of a selection algorithm is finding the median, and this necessarily takes n/2 storage. In fact, a specialized median-selection algorithm can be used to build a general selection algorithm, as in median of medians. The best-known selection algorithm is quickselect, which is related to quicksort; like quicksort, it has (asymptotically) optimal average performance, but poor worst-case performance, though it can be modified to give optimal worst-case performance as well.

Selection by sorting[edit] Rather than sorting the whole list or array, one can instead use partial sorting to select the k smallest or k largest elements. Unordered partial sorting[edit] , this still yields asymptotic complexity of O(n). Lower bounds[edit] Category:Algorithms.

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Page rank. Graphes.