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991.
Amanda L. Griffith 《Economics of Education Review》2011,30(5):1022-1033
The increasing use by private colleges and universities of financial aid based on “merit”, as opposed to based solely on financial need has caused many to raise concerns that this type of aid will go mainly to higher income students crowding out aid to lower income students. However, some analysts suggest that by attracting more “almost full-paying” students through the use of merit aid, institutions will have more financial resources that they can use to increase their financial aid to low-income students and thus their enrollment. Results using data from the College Board's Annual Survey of Colleges and other secondary data sources suggest that the increased use of merit aid is associated with a decrease in enrollment of low-income and minority students, particularly at more selective institutions. Middle and bottom tier colleges may be offsetting costs with tuition increases, as the introduction of merit aid is accompanied by an increase in net costs. 相似文献
992.
Jordan L. Neus 《Assessment & Evaluation in Higher Education》2011,36(3):301-314
Peer assessment has been gaining significant ground as a means of fostering an environment of accountability and responsibility for group projects in higher education. A popular peer assessment method assigns individual grades via a linear relationship to peer assessment scores. Using this method, a group member who receives his or her group’s average peer assessment score is assigned the instructor‐given group grade; the group member who receives a total peer assessment score of zero is assigned an individual grade of zero. Unfortunately, applying this method often requires time‐consuming exploratory data analysis because of the potential for the method to yield a high spread of grades, including grades over 100%. The present study proposes a modification, which accounts for the degree of student agreement. When the modified procedure results in a change from the group grade, the direction of change is always the same, but with smaller magnitude, requiring less subsequent data analysis and instructor time demands. Easy‐to‐modify SAS code for applying the method is presented in the Appendix. 相似文献
993.
Larry L. Howard 《Economics of Education Review》2011,30(1):157-176
This paper estimates models of the transitional effects of food insecurity experiences on children's non-cognitive performance in school classrooms using a panel of 4710 elementary students enrolled in 1st, 3rd, and 5th grade (1999-2003). In addition to an extensive set of child and household-level characteristics, we use information on U.S. counties to control for potential confounding effects of the local economic and noneconomic environment on children's household transitions between states of food insecurity and food security. The time horizon of our analysis affords insight into factors underlying children's formation of non-cognitive skills and the efficiency of classroom-based educational production in elementary school. Overall, we find significant negative developmental effects for children with food insecurity at home; and that children experiencing an early transition from food insecurity in 1st grade to food security in 3rd grade have even larger impairments that persist through 5th grade. 相似文献
994.
Lisa M. PytlikZillig Christy A. Horn Roger Bruning Stephanie Bell Xiongyi Liu Kamau O. Siwatu Mary C. Bodvarsson Doyoung Kim Deborah Carlson 《Contemporary educational psychology》2011,36(4):302-312
Two frequently-used discussion protocols were investigated as part of a program to implement teaching cases in undergraduate educational psychology classes designed for preservice teachers. One protocol involved synchronous face-to-face (FTF) discussion of teaching cases, which occurred in class after students had individually completed written case analyses as homework outside of class. The other was asynchronous computer-mediated (CM) discussion taking place outside of class, simultaneous to students’ completion of their written case analyses. Six class offerings of an undergraduate child development course taught by two instructors (three classes by each instructor) were randomly assigned within instructor in a quasi-experimental design to one of the three discussion conditions: FTF, CM, or no discussion of the cases across the semester. Findings indicated that both CM and FTF discussion conditions were associated with positive outcomes relative to the control condition. Both CM and FTF discussion related to higher cognitive–affective engagement with the cases than the control condition; and the CM discussion condition was associated with higher cognitive–affective engagement than FTF discussion. In contrast, FTF discussion, but not CM discussion, was associated with higher-than-control-condition case analysis ability at the end of the semester. Potential explanations for these findings and directions for future research are discussed. 相似文献
995.
The purpose of this study was to assess the sources of award-wining research professors’ (six women; six men) teaching self-efficacy through the framework of Bandura’s (1986) social cognitive theory. Semi-structured interviews revealed that mastery experiences and social persuasions were particularly influential sources of self-efficacy and that these sources tended to be closely related. Professors reported that their self-efficacy had generally stabilized within their first few years of assuming a tenure-track position. Participants framed negative events in adaptive ways that had little cost to their teaching self-efficacy. 相似文献
996.
The purpose of this study was to explore the nature of requisite teacher knowledge for teaching lower-track science students.
Using video accounts, student focus groups, and teacher reflections researchers documented missteps, dead-ends, and unfruitful
trajectories informed by the teacher’s incoming knowledge and compared these instances to necessary modifications informed
by students’ voices and cultural artifacts. Our study revealed the shifting nature of sociocultural and pedagogical content
knowledge of the teacher immersed in a context unlike that he experienced as a student. Results showed that teachers of majority
backgrounds could learn to teach diverse students with at least moderate success from the perspective of their students. Implications
for research and teacher education in diverse settings are discussed. 相似文献
997.
Grisham W Schottler NA McCauley LM Pham AP Ruiz ML Fong MC Cui X 《CBE life sciences education》2011,10(2):222-230
Zebra finch song behavior is sexually dimorphic: males sing and females do not. The neural system underlying this behavior is sexually dimorphic, and this sex difference is easy to quantify. During development, the zebra finch song system can be altered by steroid hormones, specifically estradiol, which actually masculinizes it. Because of the ease of quantification and experimental manipulation, the zebra finch song system has great potential for use in undergraduate labs. Unfortunately, the underlying costs prohibit use of this system in undergraduate labs. Further, the time required to perform a developmental study renders such undertakings unrealistic within a single academic term. We have overcome these barriers by creating digital tools, including an image library of song nuclei from zebra finch brains. Students using this library replicate and extend a published experiment examining the dose of estradiol required to masculinize the female zebra finch brain. We have used this library for several terms, and students not only obtain significant experimental results but also make gains in understanding content, experimental controls, and inferential statistics (analysis of variance and post hoc tests). We have provided free access to these digital tools at the following website: http://mdcune.psych.ucla.edu/modules/birdsong. 相似文献
998.
999.
1000.
Dacai Liu Zhi Liu C.L. Philip Chen Yun Zhang 《Journal of The Franklin Institute》2021,358(3):1782-1811
The existing studies on prescribed-time control cannot directly deal with nonlinear functions which don’t satisfy Lipschitz growth conditions. No results are available for prescribed-time containment control of pure-feedback UNMASs with prescribed performance. Therefore, completely unknown nonlinear function, prescribed-time tracking of system states and prescribed performance of containment errors are simultaneously considered in this paper. Fuzzy logic systems are utilized to approximate completely unknown nonlinear function. Prescribed-performance function is introduced and further incorporated into a novel speed function. Combining the proposed speed function and barrier Lyapunov function, this article presents a novel adaptive fuzzy prescribed-time containment control method which can guarantee, under prescribed performance, all followers converge to a convex formed by dynamic leaders in a prescribed time. Moreover, all tracking errors converge to predefined regions in a prescribed time. The effectiveness of the proposed prescribed-time containment control method are confirmed by strict proof and simulation. 相似文献