On Normalising Disjunctive Intermediate Logics

Prof. Jonathan Seldin, University of Lethbridge, Canada

In this talk it is shown that every intermediate logic obtained from intuitionistic logic by adding a disjunction can be normalized. However, the normalisation procedure is not as complete as that for intuitionistic and minimal logic because some results which usually follow from normalisation fail, including the separation property and the subformula property.

Jonathan P. Seldin, now Professor Emeritus, is a well-established senior scientist at the University of Lethbridge, Alberta, Canada, with an Amsterdam PhD in combinatory logic supervised by Haskell Curry. This logic, together with lambda-calculus (to which it is equivalent) is a prototype for functional languages, such as Haskell, and typed lambda-calculus is a prototype for the typing discipline in programming languages. His work on lambda-calculus, both pure and typed, has applications in formal verification, the use of formal logics to prove properties of programs (e.g., that they satisfy their specifications). He has co-authored works with Curry and Hindley on combinatory logic and lambda calculus. He is also interested in the history and philosophy of mathematics and in proof normalisation and cut-elimination for various systems of formal logic. His visit to Scotland is as a SICSA Distinguished Visiting Fellow, to work with Prof. Kamareddine at Heriot-Watt University and with Dr Dyckhoff at St Andrews. For details and publications see http://directory.uleth.ca/users/jonathan.seldin

Event details

  • When: 3rd September 2013 11:30 - 12:30
  • Where: Cole 1.33a
  • Format: Seminar

Jacob Eisenstein: Interactive Topic Visualization for Exploratory Text Analysis

Large text document collections are increasingly important in a variety of domains; examples of such collections include news articles, streaming social media, scientific research papers, and digitized literary documents. Existing methods for searching and exploring these collections focus on surface-level matches to user queries, ignoring higher-level thematic structure. Probabilistic topic models are a machine learning technique for finding themes that recur across a corpus, but there has been little work on how they can support end users in exploratory analysis. In this talk I will survey the topic modeling literature and describe our ongoing work on using topic models to support digital humanities research. In the second half of the talk, I will describe TopicViz, an interactive environment that combines traditional search and citation-graph exploration with a dust-and-magnet layout that links documents to the latent themes discovered by the topic model.
This work is in collaboration with:
Polo Chau, Jaegul Choo, Niki Kittur, Chang-Hyun Lee, Lauren Klein, Jarek Rossignac, Haesun Park, Eric P. Xing, and Tina Zhou

Jacob Eisenstein is an Assistant Professor in the School of Interactive Computing at Georgia Tech. He works on statistical natural language processing, focusing on social media analysis, discourse, and latent variable models. Jacob was a Postdoctoral researcher at Carnegie Mellon and the University of Illinois. He completed his Ph.D. at MIT in 2008, winning the George M. Sprowls dissertation award.

Event details

  • When: 23rd July 2013 13:00 - 14:00
  • Where: Cole 1.33
  • Format: Seminar

PhD Studentships – Sponsored by Time Warner Cable and Adobe

The School of Computer Science has secured support from two major companies, Time Warner Cable and Adobe, and is able to offer two fully funded PhD studentships in exciting areas of research with important applications. Both studentships are fully funded for EU applicants (covering fees, and a stipend of at least £13.5K p/a) for up to 42 months, the expected duration of the PhD. Non EU applicants may apply but may be liable for an additional approximately £11K p/a in fees.

Applicants should normally have (or expect to obtain this academic year) a 2:1 or (preferably) first class Honours Bachelors degree or equivalent in Computer Science, Computer Engineering, Software Engineering, Electrical Engineering, or a closely related topic, or a MSc (distinction preferred) in one of these subjects.

The two research topics available are:

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