1 code implementation • 21 Dec 2023 • Zixuan Chen, Subhodeep Mitra, R Ravi, Wolfgang Gatterbauer
We call this problem "ability discovery" to emphasize the connection to and duality with the more well-studied problem of "truth discovery".
no code implementations • 2 Jul 2023 • Zsolt Zombori, Agapi Rissaki, Kristóf Szabó, Wolfgang Gatterbauer, Michael Benedikt
We consider learning a probabilistic classifier from partially-labelled supervision (inputs denoted with multiple possibilities) using standard neural architectures with a softmax as the final layer.
1 code implementation • 28 Jan 2021 • Nikolaos Tziavelis, Wolfgang Gatterbauer, Mirek Riedewald
Our approach achieves strong time and space complexity properties: with $n$ denoting the number of tuples in the database, we guarantee for acyclic full join queries with inequality conditions that for every value of $k$, the $k$ top-ranked answers are returned in $\mathcal{O}(n \operatorname{polylog} n + k \log k)$ time.
Databases Data Structures and Algorithms
no code implementations • 22 Dec 2020 • Nofar Carmeli, Nikolaos Tziavelis, Wolfgang Gatterbauer, Benny Kimelfeld, Mirek Riedewald
For each of the two problems, we give a decidable characterization (under conventional complexity assumptions) of the class of tractable lexicographic orders for every CQ without self-joins.
Databases Data Structures and Algorithms
1 code implementation • 5 Mar 2020 • Krishna Kumar P., Paul Langton, Wolfgang Gatterbauer
We answer this question affirmatively and suggest a method called distant compatibility estimation that works even on extremely sparsely labeled graphs (e. g., 1 in 10, 000 nodes is labeled) in a fraction of the time it later takes to label the remaining nodes.
1 code implementation • 16 Feb 2018 • Xiaofeng Yang, Deepak Ajwani, Wolfgang Gatterbauer, Patrick K. Nicholson, Mirek Riedewald, Alessandra Sala
We therefore propose the novel notion of an any-k ranking algorithm: for a given time budget, re- turn as many of the top-ranked results as possible.
Social and Information Networks Databases Data Structures and Algorithms
no code implementations • 17 Feb 2015 • Wolfgang Gatterbauer
Belief Propagation (BP) is a widely used approximation for exact probabilistic inference in graphical models, such as Markov Random Fields (MRFs).
2 code implementations • 9 Dec 2014 • Wolfgang Gatterbauer
We derive a family of linear inference algorithms that generalize existing graph-based label propagation algorithms by allowing them to propagate generalized assumptions about "attraction" or "compatibility" between classes of neighboring nodes (in particular those that involve heterophily between nodes where "opposites attract").
no code implementations • 2 Dec 2014 • Wolfgang Gatterbauer, Dan Suciu
This paper proposes a new approach for approximate evaluation of #P-hard queries with probabilistic databases.
no code implementations • 21 Sep 2014 • Wolfgang Gatterbauer, Dan Suciu
By performing several dissociations, one can transform a Boolean formula whose probability is difficult to compute, into one whose probability is easy to compute, and which is guaranteed to provide an upper or lower bound on the probability of the original formula by choosing appropriate probabilities for the dissociated variables.
1 code implementation • 27 Jun 2014 • Wolfgang Gatterbauer, Stephan Günnemann, Danai Koutra, Christos Faloutsos
Often, we can answer such questions and label nodes in a network based on the labels of their neighbors and appropriate assumptions of homophily ("birds of a feather flock together") or heterophily ("opposites attract").
no code implementations • 23 Oct 2013 • Wolfgang Gatterbauer, Dan Suciu
We give a detailed experimental evaluation of our approach and, in the process, provide a new way of thinking about the value of probabilistic methods over non-probabilistic methods for ranking query answers.