Jonathan Wittenberg - Academia.edu (original) (raw)
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Papers by Jonathan Wittenberg
Psychodynamic Practice, 2015
European Judaism, 2006
When the great, righteous man of his generation leaves his place, its beauty and radiance are gone.
Conservative Judaism, 2009
Jewish Quarterly, 2016
The largest common embeddable subtree problem asks for the largest possible tree embeddable into ... more The largest common embeddable subtree problem asks for the largest possible tree embeddable into two input trees and generalizes the classical maximum common subtree problem. Several variants of the problem in labeled and unlabeled rooted trees have been studied, e.g., for the comparison of evolutionary trees. We consider a generalization, where the sought embedding is maximal with regard to a weight function on pairs of labels. We support rooted and unrooted trees with vertex and edge labels as well as distance penalties for skipping vertices. This variant is important for many applications such as the comparison of chemical structures and evolutionary trees. Our algorithm computes the solution from a series of bipartite matching instances, which are solved efficiently by exploiting their structural relation and imbalance. Our analysis shows that our approach improves or matches the running time of the formally best algorithms for several problem variants. Specifically, we obtain a running time of O(|T | |T |∆) for two rooted or unrooted trees T and T , where ∆ = min{∆(T), ∆(T)} with ∆(X) the maximum degree of X. If the weights are integral and at most C, we obtain a running time of O(|T | |T | √ ∆ log(C min{|T |, |T |})) for rooted trees.
For some time now scholars of medieval Hebrew poetry have regarded as untrue a commonplace held b... more For some time now scholars of medieval Hebrew poetry have regarded as untrue a commonplace held by many of the medievals themselves: namely, that whereas the Palestinian piyyut is based on rabbinic midrash, Spanish poetry relies only on the Bible." ...
Psychodynamic Practice, 2015
European Judaism, 2006
When the great, righteous man of his generation leaves his place, its beauty and radiance are gone.
Conservative Judaism, 2009
Jewish Quarterly, 2016
The largest common embeddable subtree problem asks for the largest possible tree embeddable into ... more The largest common embeddable subtree problem asks for the largest possible tree embeddable into two input trees and generalizes the classical maximum common subtree problem. Several variants of the problem in labeled and unlabeled rooted trees have been studied, e.g., for the comparison of evolutionary trees. We consider a generalization, where the sought embedding is maximal with regard to a weight function on pairs of labels. We support rooted and unrooted trees with vertex and edge labels as well as distance penalties for skipping vertices. This variant is important for many applications such as the comparison of chemical structures and evolutionary trees. Our algorithm computes the solution from a series of bipartite matching instances, which are solved efficiently by exploiting their structural relation and imbalance. Our analysis shows that our approach improves or matches the running time of the formally best algorithms for several problem variants. Specifically, we obtain a running time of O(|T | |T |∆) for two rooted or unrooted trees T and T , where ∆ = min{∆(T), ∆(T)} with ∆(X) the maximum degree of X. If the weights are integral and at most C, we obtain a running time of O(|T | |T | √ ∆ log(C min{|T |, |T |})) for rooted trees.
For some time now scholars of medieval Hebrew poetry have regarded as untrue a commonplace held b... more For some time now scholars of medieval Hebrew poetry have regarded as untrue a commonplace held by many of the medievals themselves: namely, that whereas the Palestinian piyyut is based on rabbinic midrash, Spanish poetry relies only on the Bible." ...