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971.
J. Daniel Kim 《Research Policy》2018,47(3):637-649
While startups are the center of extensive policy discussion given their outsized role in job creation, it is not clear whether they create high quality jobs relative to incumbent firms. This paper investigates the wage differential between venture capital-backed startups and established firms, given that the two firm types compete for talent. Using data on MIT graduates, I find that non-founder employees at VC-backed startups earn roughly 10% higher wages than their counterparts at established firms. To account for unobserved heterogeneity across workers, I exploit the fact that many MIT graduates receive multiple job offers. I find that wage differentials are statistically insignificant from zero when individual fixed effects are included. This implies that much of the startup wage premium in the cross-section can be attributed to selection, and that VC-backed startups pay competitive wages for talent. To unpack the selection mechanism, I show that individual preferences for risk as well as challenging work strongly predict entry into VC-backed startups. 相似文献
972.
973.
Yanwei Huang Yu He Howard Sheng Xia Lu Haini Dong Sudeshna Samanta Hongliang Dong Xifeng Li Duck Young Kim Ho-kwang Mao Yuzi Liu Heping Li Hong Li Lin Wang 《国家科学评论(英文版)》2019,6(2):239
Lithium titanium oxide (Li4Ti5O12, LTO), a ‘zero-strain’ anode material for lithium-ion batteries, exhibits excellent cycling performance. However, its poor conductivity highly limits its applications. Here, the structural stability and conductivity of LTO were studied using in situ high-pressure measurements and first-principles calculations. LTO underwent a pressure-induced amorphization (PIA) at 26.9 GPa. The impedance spectroscopy revealed that the conductivity of LTO improved significantly after amorphization and that the conductivity of decompressed amorphous LTO increased by an order of magnitude compared with its starting phase. Furthermore, our calculations demonstrated that the different compressibility of the LiO6 and TiO6 octahedra in the structure was crucial for the PIA. The amorphous phase promotes Li+ diffusion and enhances its ionic conductivity by providing defects for ion migration. Our results not only provide an insight into the pressure depended structural properties of a spinel-like material, but also facilitate exploration of the interplay between PIA and conductivity. 相似文献
974.
For further information, write to Kim Stoddard, College of Education, University of South Florida—St. Petersburg, 140 7th
Ave. South, St. Petersburg, FL 33701. 相似文献
975.
976.
Young Mi Kim 《Prospects》1987,17(1):107-114
977.
This study identifies the state and characteristics of theoretical research in library and information science journals by examining the number and the quality of theory incidents. Theory incident is characterized as an event in which the author contributes to the development or the use of theory in his/her own paper. This study assumes that both theory building and theory use are intertwined to construct a cohesive body of knowledge in the filed. Theory incidents were identified by a content analysis of 1661 articles in four LIS journals from 1984 to 2003. The findings suggest that 41.4% of the articles contributed to the development or use of theory. The overall proportion of theoretical articles has increased. They showed a tendency to converge into a few subfields, such as information seeking and use or information retrieval. However, the declining share of theory development articles in recent journal issues and the overall low level of theory incidents are urging LIS researchers to the importance of continuous and creative research in LIS. 相似文献
978.
Alliances with established organizations provide young firms with resources necessary for survival. We build on recent organizational research examining the effect of upper echelons on attracting powerful intermediaries to understand how young biotechnology firms establish alliances with established organizations. Drawing upon the concept of homophily, we test hypotheses regarding the extent to which young firms and partners match along specific homophily dimensions. Our findings from an event-history analysis of 3,200 career histories of managers who took biotechnology firms public between 1979 and 1996 show that alliance formation is related to status homophily and role-based homophily between young and established organizations. 相似文献
979.
The Danish e-commerce strategy is a highly ambitious effort to become the world's leading IT nation. Instead of a production-led approach aimed at stimulating domestic hardware and software production, Denmark has pursued a demand-oriented approach focused on promoting the widespread adoption of e-commerce in the Danish society. The Danish government has developed a number of e-commerce initiatives via public-private sector partnerships--an approach we refer to as "governance." So far, it appears that Denmark has been successful in promoting business-to-business (B2B) e-commerce, with a number of Danish companies being global leaders in the use of B2B applications. On the other hand, Denmark has had less success in achieving widespread use of business-to-consumer (B2C) e-commerce. This article analyzes the Danish national environment for e-commerce, discusses four sets of governance initiatives aimed at the development of e-commerce, and analyzes the reasons for its success in B2B and relative failure in B2C adoption. 相似文献
980.
Catherine A. Dobris Kim White-Mills Rachel D. Davidson Toula V. Wellbrook 《Communication quarterly》2017,65(1):39-59
Dr. Spock’s, The Common Sense Book of Baby and Child Care, one of the best-selling self-help texts of all-time, “second only to the Bible in popularity” (Meakin & Tattersall, 2004) was one of the most influential childcare books in American culture. The author has been both heralded and disparaged as instrumental in the shaping of untold generations. In the present study, we address the rhetorical construction of the Spockian Mother as she is developed during Spock’s tenure from 1946–1992. We employ a feminist rhetorical perspective to examine the progression of Spock’s texts in order to understand how patriarchal images of motherhood are constructed and maintained through Spock’s lifetime and the first 46 years of its publication. We argue that Spock both reinforced and challenged the institution of motherhood; he challenged institutionalized motherhood by encouraging mothers to “trust themselves” while simultaneously conforming to a patriarchal model of motherhood which is at odds with empowered mothering. 相似文献