Externalities, technological complementarities and sustained economic growth

Externalities as conventionally defined miss many of the spillovers that are both causes and consequences of the technological changes that underlie economic growth. We introduce a much wider concept called technological complementarities. New general purpose technologies (GPTs) rejuvenate the growth process by creating technological complementarities, which are adequately measured neither by total factor productivity (TFP) nor by externalities. There would be major gains from technological change even if the returns on capital invested in innovation never exceeded the returns on investing in existing technologies so that there were neither externalities nor positive changes in TFP.     

The role of social embeddedness in professorial entrepreneurship: a comparison of electrical engineering and computer science at UC Berkeley and Stanford

Professorial entrepreneurship has recently attracted much attention. This paper draws upon historical research, a survey of faculty, and an Internet-based methodology for identifying professorial affiliations with entrepreneurial firms at two of the premier electrical engineering and computer science departments in the US, The University of California, Berkeley and Stanford. We employ the concept of “nested embeddedness” to explain why the faculty members in these two institutions have different levels of entrepreneurship and corporate involvement. EE&CS faculty at both universities were found to be socially embedded in departments and disciplines that supported and placed value on entrepreneurial activities. However, while being embedded in a university environment with a history of success and high level of support for entrepreneurship, EE&CS faculty at Stanford had a significantly greater level of corporate involvement, including the founding of start-ups. Although significantly less than Stanford, the level of corporate involvement among EE&CS faculty at Berkeley was also substantial. This suggests that being embedded in an academic department and disciplines with cultures that are supportive of entrepreneurial activity can help counteract the disincentives created by a university environment that is not strongly supportive of these activities.     

Identifying future scientists: predicting persistence into research training

This study used semistructured interviews and grounded theory to look for characteristics among college undergraduates that predicted persistence into Ph.D. and M.D./Ph.D. training. Participants in the summer undergraduate and postbaccalaureate research programs at the Mayo Clinic College of Medicine were interviewed at the start, near the end, and 8–12 months after their research experience. Of more than 200 themes considered, five characteristics predicted those students who went on to Ph.D. and M.D./Ph.D. training or to M.D. training intending to do research: 1) Curiosity to discover the unknown, 2) Enjoyment of problem solving, 3) A high level of independence, 4) The desire to help others indirectly through research, and 5) A flexible, minimally structured approach to the future. Web-based surveys with different students confirmed the high frequency of curiosity and/or problem solving as the primary reason students planned research careers. No evidence was found for differences among men, women, and minority and nonminority students. Although these results seem logical compared with successful scientists, their constancy, predictive capabilities, and sharp contrast to students who chose clinical medicine were striking. These results provide important insights into selection and motivation of potential biomedical scientists and the early experiences that will motivate them toward research careers.     

Teachers' education, classroom quality, and young children's academic skills: results from seven studies of preschool programs

In an effort to provide high-quality preschool education, policymakers are increasingly requiring public preschool teachers to have at least a Bachelor's degree, preferably in early childhood education. Seven major studies of early care and education were used to predict classroom quality and children's academic outcomes from the educational attainment and major of teachers of 4-year-olds. The findings indicate largely null or contradictory associations, indicating that policies focused solely on increasing teachers' education will not suffice for improving classroom quality or maximizing children's academic gains. Instead, raising the effectiveness of early childhood education likely will require a broad range of professional development activities and supports targeted toward teachers' interactions with children.     

Developmental Precursors of Relational Aggression From Late Childhood Through Adolescence

Relational aggression—a psychological form of aggression—has numerous negative consequences for physical and emotional health. However, little is known about the risk factors that lead youth to engage in relational aggression. Using multimethod data from a longitudinal research of 674 Mexican-origin youth, this study examined the influence of parents, siblings, and peers on the development of relational aggression. Increases in relational aggression from age 10 to 16 were associated with: (a) low levels of parental monitoring and (b) increased association with deviant peers and siblings. These results held across gender and nativity status. The findings suggest that multiple socialization agents contribute to the development of relational aggression. We discuss the practical implications for reducing relational aggression during adolescence.     

Brief Report on PROSPER Academic Outcomes: Extended Model of Crossover Effects on Young Adult College Success

This study examines crossover effects of adolescent substance misuse preventive interventions on academic success in college. It evaluates pathways of influence on college grades, via effects on school engagement, problem-solving skills, and substance misuse in high school. Data were collected as part of an Randomized Controlled Trial (RCT) evaluating a multicomponent intervention conducted in 28 school districts with middle school students. At age 19, study participants (N = 1,488) enrolled in college reported on college grades. The model fit the data, supporting hypothesized pathways of intervention impacts. Inclusion of a significant direct effect on college grades further improved model fit. Results support the potential for universal substance misuse preventive interventions delivered by community partnerships during middle school to yield effects on long-term academic success.     

Elementary teachers’ science subject matter knowledge across the teacher career cycle

Although widely touted as important, there is little evidence regarding the influence of teaching experience on elementary teachers' science subject matter knowledge (SMK). To better understand this phenomenon, we administered an assessment of science topics taught in the fifth and sixth grades to 169 preservice teachers, 231 fifth-grade teachers, and 208 sixth-grade teachers. We then compared the mean scores of teachers at different stages in the career cycle using one-way and two-way ANOVA and explored the relationship between SMK scores and years of teaching experience using regression analysis. Findings indicate that (i) being assigned to a specific grade level had an impact on teachers' SMK for topics included in the grade level, (ii) teachers' SMK scores were lower later in their careers for both science topics they had never taught and for science topics they were responsible for teaching, and (iii) results differed for fifth and sixth grades. This study adds to the existing literature through the examination of a large sample of elementary teachers, with teachers of varying years of experience, while focusing on the science topics these teachers are responsible for teaching. The results of this study provide strong evidence that (i) years of experience teaching specific science topics is associated with the development of teachers' knowledge of these topics, and (ii) teaching experience, what teachers do in the context of their everyday practice, can be an effective means of self-directed learning for teachers. There is also evidence that this influence is not uniform across years of teaching experience or science topics taught. These findings raise important implications about future research into the mechanism of SMK development through teaching experience and teacher grade-level assignments.     

Enhancement of Anatomical Education Using Augmented Reality: An Empirical Study of Body Painting

Students in undergraduate premedical anatomy courses may experience suboptimal and superficial learning experiences due to large class sizes, passive lecture styles, and difficult-to-master concepts. This study introduces an innovative, hands-on activity for human musculoskeletal system education with the aim of improving students’ level of engagement and knowledge retention. In this study, a collaborative learning intervention using the REFLECT (augmented reality for learning clinical anatomy) system is presented. The system uses the augmented reality magic mirror paradigm to superimpose anatomical visualizations over the user’s body in a large display, creating the impression that she sees the relevant anatomic illustrations inside her own body. The efficacy of this proposed system was evaluated in a large-scale controlled study, using a team-based muscle painting activity among undergraduate premedical students (n = 288) at the Johns Hopkins University. The baseline knowledge and post-intervention knowledge of the students were measured before and after the painting activity according to their assigned groups in the study. The results from knowledge tests and additional collected data demonstrate that the proposed interactive system enhanced learning of the musculoskeletal system with improved knowledge retention (F_(10,133) = 3.14, P < 0.001), increased time on task (F_(1,275) = 5.70, P < 0.01), and a high level of engagement (F_(9,273) = 8.28, P < 0.0001). The proposed REFLECT system will be of benefit as a complementary anatomy learning tool for students.