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The effects of school reform under NCLB waivers: Evidence from focus schools in Kentucky.
Under waivers to the No Child Left Behind (NCLB) Act, the federal government required states to identify schools where targeted subgroups of students have the lowest achievement and to implement reforms in these âFocus Schools.â In this study, we examine the Focus School reforms in the state of Kentucky. The reforms in this state are uniquely interesting for several reasons. One is that the state developed unusually explicit guidance for Focus Schools centered on a comprehensive school-planning process. Second, the state identified Focus Schools using a âsuper subgroupâ measure that combined traditionally low-performing subgroups into an umbrella group. This design feature may have catalyzed broader whole-school reforms and attenuated the incentives to target reform efforts narrowly. Using regression discontinuity designs, we find that these reforms led to substantial improvements in school performance, raising math achievement by 17 percent and reading achievement by 9 percent
Air ion concentration under overhead high-voltage transmission lines
This paper reports air ion concentration monitored at 41 sites under overhead high voltage ac power lines in and around an urban environment. The net ionic polarity under power lines was of both signs but mostly positive, and concentrations varied widely from 0 to 3300 ions cm-3. Concomitant measurements of the vertical dc electric field at the ground confirmed the presence of a net positive charge above. Approximately 19% of the sites exhibited relatively high ion concentrations exceeding 1000 cm-3. The mean value of all the sites was 776 cm-3. Statistically, the mean for the transmission voltage (220-330 kV) line sites was significantly higher than that for the sub-transmission voltage (110-132 kV) line sites with means of 905 and 501 cm-3 respectively. These values were compared with the mean urban outdoor concentration well away from the lines which was about 400 cm-3 and of negative polarity. Overall, ion concentrations at approximately 76% of the power line sites exceeded the absolute mean urban outdoor value. The dc electric fields under the power lines showed a statistically significant relationship to the measured ion concentrations, although there was considerable scatter to indicate that electric field measurements do not necessarily reflect air ion concentrations at ground level
Technology education teacher development in solomon islands: Enhancing teachersâ perceptions and classroom practices
Technology education in the Solomon Islands is in the process of change with the curriculum being developed into a more broad technological literacy approach, comprising of technological knowledge, technological practices, and the nature of technology. This paper is based on a two-year study (2005 and 2006) with secondary technology education teachers in the Solomon Islands. The first year of the research revealed that technology teachers in the Solomon Islands held narrow perspectives of technology and technology education, with views centering on narrow technical aspects. Classroom practices were teacher-dominated and authoritarian. Most teaching approaches included rote learning. A professional development programme based on the principles of teacher reflection, teacher support, and on-going professional development was undertaken. Workshop days were interspersed with classroom practice. The programme focussed on developing teachersâ views of the nature of technology and learning in technology education, assisting teachers in planning for effective technology teaching and introducing the concept of assessment for effective technology learning. It impacted on teachersâ perceptions and classroom practices. Changes included the teachersâ perceptions of technology and technology education, the teachersâ teaching documents, the teaching pedagogy, the teachersâ assessment practices and the studentsâ learning styles
Competition and Cooperation in Divisible Good Auctions: An Experimental Examination
An experimental approach is used to examine the performance of three different multi-unit auction designs: discriminatory, uniform-price with fixed supply, and uniform-price with endogenous supply. We find that the strategies of the individual bidders and the aggregate demand curves are inconsistent with theoretically identified equilibrium strategies. The discriminatory auction is found to be more susceptible to collusion than are the uniform-price auctions, and so contrary to theoretical predictions and previous experimental results the discriminatory auction provides the lowest average revenue. Consistent with theoretical predictions, bidder demands are more elastic with reducible supply or discriminatory pricing than in the uniform-price auction with fixed supply. Despite a lack of a priori differences across bidders, the discriminatory auction results in significantly more symmetric allocations.
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