13000609
Disambiguating Geographic Names in a Historical Digital Library
Geographic interfaces provide natural, scalable visualizationss for many digital library collections, but the wide range of data in digital libraries presents some particular problems for identifying and disambiguating place names. We describe the toponym-disambiguation system in the Perseus digital library and evaluate its performance. Name categorization varies significantly among different types of documents, but toponym disambiguation performs at a high level of precision and recall with a gazetteer an order of magnitude larger than most other applications.
11578326
Drudgery and deep thought
2813562
Context-Based Morphological Disambiguation with Random Fields
Finite-state approaches have been highly successful at describing the morphological processes of many languages. Such approaches have largely focused on modeling the phone- or character-level processes that generate candidate lexical types, rather than tokens in context. For the full analysis of words in context, disambiguation is also required (Hakkani-Tur et al., 2000; Hajic et al., 2001). In this paper, we apply a novel source-channel model to the problem of morphological disambiguation (segmentation into morphemes, lemmatization, and POS tagging) for concatenative, templatic, and inflectional languages. The channel model exploits an existing morphological dictionary, constraining each word's analysis to be linguistically valid. The source model is a factored, conditionally-estimated random field (Lafferty et al., 2001) that learns to disambiguate the full sentence by modeling local contexts. Compared with baseline state-of-the-art methods, our method achieves statistically significant error rate reductions on Korean, Arabic, and Czech, for various training set sizes and accuracy measures.
15706733
Integrating harvesting into digital library content
The Open Archives Initiative has gained success by aiming between complex federation schemes and low functionality web crawling. Much information still remains hidden inside documents catalogued by OAI metadata. We discuss how subdocument information can be exposed by data providers and exploited by service providers. We discuss services for citation reversal and name and term linking with harvested data in the Perseus Project's document management system and a proxy service for automatically adding these links to OAI documents outside Perseus.
1432381
Detecting and Browsing Events in Unstructured text
Previews and overviews of large, heterogeneous information resources help users comprehend the scope of collections and focus on particular subsets of interest. For narrative documents, questions of "what happened? where? and when?" are natural points of entry. Building on our earlier work at the Perseus Project with detecting terms, place names, and dates, we have exploited co-occurrences of dates and place names to detect and describe likely events in document collections. We compare statistical measures for determining the relative significance of various events. We have built interfaces that help users preview likely regions of interest for a given range of space and time by plotting the distribution and relevance of various collocations. Users can also control the amount of collocation information in each view. Once particular collocations are selected, the system can identify key phrases associated with each possible event to organize browsing of the documents themselves.
11953962
Detecting events with date and place information in unstructured text
Digital libraries of historical documents provide a wealth of information about past events, often in unstructured form. Once dates and place names are identified and disambiguated, using methods that can differ by genre, we examine collocations to detect events. Collocations can be ranked by several measures, which vary in effectiveness according to type of events, but the log-likelihood measure (-2 log λ) offers a reasonable balance between frequently and infrequently mentioned events and between larger and smaller spatial and temporal ranges. Significant date-place collocations can be displayed on timelines and maps as an interface to digital libraries. More detailed displays can highlight key names and phrases associated with a given event.
12947717
The evolving mSpace platform: leveraging the semantic web on the trail of the memex
Vannevar Bush proposed the memex as a means to support building knowledge in the way he says the human brain works: by association. Achieving this vision has been a core motivation for hypertext research. In this paper, we suggest first that Bush's memex reflects an interaction paradigm rather than system design. Second, we propose that Semantic Web promises to provide the mechanisms to enable these interaction requirements. Third, we propose the mSpace framework and architecture as a platform to deploy lightweight Semantic Web applications which foreground associative interaction. We propose this lightweight approach as a means to evaluate both interaction needs and the cost/benefits of using Semantic Web technologies to support them.
2964234
Random Trees and the Analysis of Branch and Bound Procedures
Branch and bound procedures are the most efficient known means for solving many NP-hard problems A special class of branch and bound procedures called relaxation-gutded procedures ig presented. While for some branch and bound procedures a worst-case complexity bound is known, the average case complexity is usually unknown, despite the fact that it may g~ve more useful information about the performance of the algorithm. A random process which generates labeled trees is introduced as a model of the kind of trees that a relaxatlon-gutded procedure generates over random instances of a problem Results concerning the expected time and space complexity of searching these random trees are derived with respect to several search strategies. The best-bound search strategy is shown to be optimal in both time and space. These results are illustrated by data from random traveling salesman instances Evidence ~s presented that the asymmetric traveling salesman problem can be solved exactly in time O(n31n(n)) on the average. Categories and Subject Descnptors: F.2.2 [Analysis of Algorithms and Problem Complexity]: Nonnumencal Algorithms and Problems, G.2.1 [Discrete Mathematics]: Combinatorics; G.I.6 [Numerical Analysis]. OpUmlzatlon General Terms: Algorithms, Theory Addlttonal
16933924
Using architecture evaluation to prepare a large Web based system for evolution
This paper describes an ongoing effort to develop architecture documentation and to evaluate the architecture using the Architecture Tradeoff Analysis Method/sup SM/ (ATAM/sup SM/). The system is a large Web based application using J2EE, portal and Web services technology that is replacing a large number of legacy applications. It has very detailed documentation at the design level, but is lacking overall architecture documentation. We describe how the architecture is being documented in an iterative manner, and how sample scenarios are being developed as input for an ATAM. The package of the documentation, scenarios and ATAM will fill in important gaps in existing knowledge, and it will provide an important baseline for the system's evolution.
8267445
Explaining design plans
The paper describes a methodology for generating quality explanations from design plans. In selecting items of information for inclusion in an explanation, the methodology considers the rationales behind the strategic knowledge and object-level knowledge specified in a design plan. Rhetorical structure theory and discourse focus tracking are utilised to determine textual structure, and to maintain discourse coherence and cohesion. Using a simple system of user modelling, it is shown how the methodology flexibly includes consideration of a user's knowledge, thus resulting in more focused and convincing explanations. The methodology is used to investigate follow-up explanations, and the generation of explanations from plans which contain a misconception on the part of the designer.
45395534
A Study of Permutation Crossover Operators on the Traveling Salesman Problem