The Effect of Positive Faculty Support on Mathematical Self-Concept for Male and Female Students in STEM Majors

Using hierarchical linear modeling, this study examined how positive faculty support is associated with mathematical self-concept development among students in STEM fields and how the association differs for male and female students. The study utilized data from the 2003 Freshman Survey and the 2007 College Senior Survey (CSS) and a sample of 2184 students across 27 baccalaureate institutions nationwide. This study found that positive faculty support was significantly and positively related to STEM students’ mathematical self-concept development in general; however, this positive connection held for male STEM students only. Findings also suggested that female STEM students’ mathematical self-concept remained significantly below males’ throughout college and positive faculty support did not narrow the persistent gender gap in this area. The study discusses the theoretical and practical implications of the findings.     

Reflexivity,positionality and power in cross-cultural participatory action research with research assistants in rural Cambodia

This paper draws on the experiences of a doctoral student undertaking a cross-cultural, cross-language participatory action research (PAR) project in rural Cambodia. Cambodia is a largely Buddhist country with a complex history of religion, invasion, colonisation, war and oppression. Despite a democratic constitution, political control and fear of challenging authority are ever present; and all had an impact on the participation and development of this project. I recruited eight volunteer community health workers (CHWs) and two research assistants (RAs) with an aim to explore methods and challenges faced when trying to improve health with and for community members. Over eight participatory workshops and a two-day training session CHWs identified, implemented and reflected on solutions to community health problems. Simultaneously, the RAs and I reflected on the processes and challenges we faced. Creating opportunity for reflexivity allowed for discussion to emerge around culture, position and power and how these were impacting on the research process and outcomes. Established social hierarchical power structures in Cambodia presented challenges to undertaking a PAR project with emancipatory and social change aims. Such structures also impacted on the ability and readiness of participants to be critical and analytical. The importance of the RAs as cultural navigators and the necessity of embracing their situated knowledge as both an insider and outsider is a key finding.     

Is there a startup wage premium? Evidence from MIT graduates

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.     

大学文凭价值几何？

A new report estimates--to the dollar---how much a degree boosts your income and other benefits.     

Li-ion battery material under high pressure: amorphization and enhanced conductivity of Li4Ti5O12

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.     

Integrating special-needs children into a preschool setting

For further information, write to Kim Stoddard, College of Education, University of South Florida—St. Petersburg, 140 7th Ave. South, St. Petersburg, FL 33701.     

An analysis of the development and use of theory in library and information science research articles

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.     

Where do alliances come from?: The effects of upper echelons on alliance formation

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.