A competitive environment for exploratory query expansion

Most information workers query digital libraries many times a day. Yet people have little opportunity to hone their skills in a controlled environment, or compare their performance with others in an objective way. Conversely, although search engine logs record how users evolve queries, they lack crucial information about the user's intent. This paper describes an environment for exploratory query expansion that pits users against each other and lets them compete, and practice, in their own time and on their own workstation. The system captures query evolution behavior on predetermined information-seeking tasks. It is publicly available, and the code is open source so that others can set up their own competitive environments

Integration: An Empirical Assessment of Russia

In the process of implementing market reforms, many post-socialist countries have struggled to preserve economic and political integration. Using a statistical model of commodity trade, we quantify the evolution of economic integration observed among regions within Russia during 1995-1999, and then explore potential determinants of the patterns of integration we observe. Our measure of integration exhibits rich regional variation that, when aggregated to the national level, fluctuates substantially over time. In seeking to account for this behavior, we draw in part on theoretical models that emphasize the potential role of openness to international trade, regional disparities in income, and inflation volatility in threatening economic and political integration. Controlling for a host of additional regional- and national-level variables, we find a strong negative correspondence between openness to international trade and internal economic integration within Russia. We also find negative links but weaker links between integration and regional-income disparities and inflation volatility.http://deepblue.lib.umich.edu/bitstream/2027.42/39873/3/wp488.pd

Extracting corpus specific knowledge bases from Wikipedia

Thesauri are useful knowledge structures for assisting information retrieval. Yet their production is labor-intensive, and few domains have comprehensive thesauri that cover domain-specific concepts and contemporary usage. One approach, which has been attempted without much success for decades, is to seek statistical natural language processing algorithms that work on free text. Instead, we propose to replace costly professional indexers with thousands of dedicated amateur volunteers--namely, those that are producing Wikipedia. This vast, open encyclopedia represents a rich tapestry of topics and semantics and a huge investment of human effort and judgment. We show how this can be directly exploited to provide WikiSauri: manually-defined yet inexpensive thesaurus structures that are specifically tailored to expose the topics, terminology and semantics of individual document collections. We also offer concrete evidence of the effectiveness of WikiSauri for assisting information retrieval

Tidal Disruption Of Neutron Stars By Black-Holes In Close Binaries

NSF AST 74-21216Astronom

Entrepreneurship and Post-Socialist Growth

A growing body of national-level survey evidence indicates that small-scale entrepreneurial activity has been an important engine of growth in post-socialist economies. Here we use a rich regional data set to obtain a statistical characterization of the relationship between entrepreneurial activity and economic growth within post-Soviet Russia. Russia is a useful laboratory for evaluating links between entrepreneurial activity and growth because of the striking variation in initial conditions, the adoption of policy reforms, and entrepreneurial activity observed across its large number of regions in the early stages of transition. Russia has also experienced striking regional variation in subsequent growth. Conditional on variations in initial conditions and policy reform measures, we find that regional entrepreneurial activity exhibits a strong and enduring relationship with subsequent growth.http://deepblue.lib.umich.edu/bitstream/2027.42/39790/3/wp406.pd