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We build a new concordance between the NBER Patent Data and U.S. Census microdata and use it to examine what happens when firms patent. We find strong evidence that increases in patent stock are associated with increases in firm size, scope, and skill and capital intensity. We find somewhat weaker evidence that changes in patenting are positively correlated with changes in total factor productivity. We also analyze first-time patentees and find similar effects following initial patent application. Together, these results suggest that patenting is indeed associated with real changes within firms, in particular with growth through increases in scope. © 2011 The President and Fellows of Harvard College and the Massachusetts Institute of Technology.

Long queries form a difficult, but increasingly important segment for web search engines. Query reduction, a technique for dropping unnecessary query terms from long queries, improves performance of ad-hoc retrieval on TREC collections. Also, it has great potential for improving long web queries (upto 25% improvement in NDCG@5). However, query reduction on the web is hampered by the lack of accurate query performance predictors and the constraints imposed by search engine architectures and ranking algorithms.In this paper, we present query reduction techniques for long web queries that leverage effective and efficient query performance predictors. We propose three learning formulations that combine these predictors to perform automatic query reduction. These formulations enable trading off average improvements for the number of queries impacted, and enable easy integration into the search engine's architecture for rank-time query reduction. Experiments on a large collection of long queries issued to a commercial search engine show that the proposed techniques significantly outperform baselines, with more than 12% improvement in NDCG@5 in the impacted set of queries. Extension to the formulations such as result interleaving further improves results. We find that the proposed techniques deliver consistent retrieval gains where it matters most: poorly performing long web queries.

This paper examines how the enforceability of noncompete covenants affects the creation, growth, and survival of spinouts and other new entrants. The impact of noncompete enforceability on new firms is ambiguous, since noncompetes reduce knowledge leakage but impose hiring costs. However, we posit that enforceability screens formation of within-industry spinouts (WSOs) relative to non-WSOs by dissuading founders with lower human capital. Using data on 5.5 million new firms, we find greater enforceability is associated with fewer WSOs, but relative to non-WSOs, WSOs that are created tend to start and stay larger, are founded by higher-earners, and are more likely to survive their initial years. In contrast, we find no impact on non-WSO entry and a negative effect on size and short-term survival. The online appendix is available at https://doi.org/10.1287/mnsc.2016.2614 . This paper was accepted by David Hsu, entrepreneurship and innovation.