The evolution of inventor networks in the Silicon Valley and Boston regions

While networks are widely thought to enhance regional innovative capability, there exist few longitudinal studies of their formation and evolution over time. Based on an analysis of all patenting inventors in the U.S. from 1975 to 2002, we observe dramatic aggregation of the regional inventor network in Silicon Valley around 1989. Based on network statistics, we argue that the sudden rise of giant networks in Silicon Valley can be understood as a phase transition during which small isolated networks form one giant component. By contrast, such a transition in Boston occurred much later and much less dramatically. We do not find convincing evidence that this marked difference between the two regions is due to regional differences in the propensity to collaborate or the involvement of universities in patenting. Interviews with key network players suggest that contingent labor mobility between established firms in Silicon Valley, in particular resulting from IBM’s policy as a central player in patenting activity, promoted inter-organizational networking, leading to larger inventor networks.evolutionary economic, inventor networks

Transferring Your Farm Business to the Next Generation

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Informational Complexity and the Flow of Knowledge across social boundaries

Scholars from a variety of backgrounds – economists, sociologists, strategists, and students of technology management – have sought a better understanding of why some knowledge disperses widely while other knowledge does not. In this quest, some researchers have focused on the characteristics of the knowledge itself (e.g., Polanyi, 1966; Reed and DeFillippi, 1990; Zander and Kogut, 1995) while others have emphasized the social networks that constrain and enable the flow of knowledge (e.g., Coleman et al., 1957; Davis and Greve, 1997). This chapter examines the interplay between these two factors. Specifically, we consider how the complexity of knowledge and the density of social relations jointly influence the movement of knowledge. Imagine a social network composed of patches of dense connections with sparse interstices between them. The dense patches might reflect firms, for instance, or geographic regions or technical communities. When does knowledge diffuse within these dense patches circumscribed by social boundaries but not beyond them? Synthesizing social network theory with a view of knowledge transfer as a search process, we argue that knowledge inequality across social boundaries should reach its peak when the underlying knowledge is of moderate complexity. To test this hypothesis, we analyze patent data and compare citation rates across three types of social boundaries: within versus outside the firm, geographically near to versus far from the inventor, and internal versus external to the technological class. In all three cases, the disparity in knowledge diffusion across these borders is greatest for knowledge of an intermediate level of complexity.evolutionary economics, informational complexity, knowledge flow, social boundaries

Student Persistence in Associate Degree Nursing Programs at Mississippi Community Colleges

The purpose of this study was to examine factors of student persistence and attrition in addition to strategies that may help students persist in associate degree nursing programs at community colleges. Data were collected from nursing students enrolled in first-year associate degree nursing programs at participating Mississippi community colleges and analyzed using multiple regression and repeated measures ANOVAs. Tinto’s Classic Model and Bean & Metzner’s Nontraditional Model of Student Attrition were utilized in this study. This mixed methods convenience sample yielded 564 participants, and the results were as follows: environmental factors and demographic factors of student persistence were found to be significant predictors with gender being significant, and there was a statistically significant difference between academic, social integration, and environmental factors with environmental factors having a greater difference. This should be examined with a degree of caution since the Cronbach alpha of environmental factors was lower than .70. Further research should be conducted at other institutions and care should be taken to not generalize

Calculating ϵ′/ϵ\epsilon'/\epsilon using HYP staggered fermions

We present preliminary results for $\epsilon'/\epsilon$ calculated using HYP staggered fermions in the quenched approximation. We compare different choices of quenched penguin operators.Comment: 3 pages, 4 figures, Contribution to Lattice 2004 International Symposiu

“WE SANG ALLELUIA, PRAISE THE LORD!”: AFRICAN-AMERICAN IDENTITY AND THE USE AND RECEPTION OF MUSIC WITHIN A SEVENTH-DAY ADVENTIST CHURCH IN NEW YORK CITY, 1970 – 2010

The Ephesus Seventh-day Church, one of the first Black SDA churches that were formed in the New York City area during the late 1920s and early 1930s, is one church that has been faced with the challenge of maintaining traditional repertoire and musical practices, while including more popular genres and styles that lay outside the SDA guidelines. Located in Central Harlem, Ephesus is surrounded by the cultural and historical influences within the Harlem community. The Ephesus Church, based on extant hymnals and the recollections of church members, continued in the Euro-centric musical traditions of early SDA churches until the 1960s, when it began to explore African-inspired musical practices. Around 1970, close in time to the SDA 1972 Music Guidelines were instituted, a struggle between Euro-centric versus Afro-centric musical cultures became apparent. Following introductory chapters on the history of African-American membership in the SDA Church from the 19th century to the early 20th century and early musical leaders of Ephesus Church, the musical practices of Ephesus from 1970 to 2010 serves as the focus of this study

Neutron-scattering study of spin correlations in La1.94-xSrxCe0.06CuO4

We performed a neutron-scattering experiment to investigate the effect of distortion of CuO2 planes on the low-energy spin correlation of La1.94-xSrxCe0.06CuO4 (LSCCO). Due to the carrier-compensation effect by co-doping of Sr and Ce, LSCCO has a smaller orthorhombic lattice distortion compared to La2-xSrxCuO4 (LSCO) with comparable hole concentration p. A clear gap with the edge-energy of 6~7 meV was observed in the energy spectrum of local dynamical susceptibility c"(w) for both x=0.18 (p~0.14) and x=0.24 (p~0.20) samples as observed for optimally-doped LSCO (x=0.15~0.18). For the x=0.14 (p~0.10) sample, in addition to the gap-like structure in c"(w) we observed a low-energy component within the gap which develops below 2~3meV with decreasing the energy. The low-energy component possibly coincides with the static magnetic correlation observed in this sample. These results are discussed from a view point of relationship between the stability of low-energy spin fluctuations and the distortion of CuO2 planes.Comment: 4 pages, 3 figures, proceeding for SNS2007 conferenc