The Effect of Private School Vouchers on Political Participation: Experimental Evidence From New York City

In 1997, the New York School Choice Scholarships Foundation Program (SCSF) randomly offered three-year scholarships to attend private schools to approximately 1,000 low-income families in New York City. In this paper we leverage exogenous variation generated by the SCSF to estimate the causal effect of the private school voucher offer—and the private school attendance it induced—on later-life voter registration and turnout outcomes. Our results demonstrate that the voucher intervention had no effect on registering to vote or voting in any of several elections for either the full sample or any of several demographic subgroups. Although unique aspects of the SCSF context impose limits on the scope of our results, they have clear implications for assessing the relative effectiveness of public and private schools in preparing democratic citizens. We close the paper by discussing the implications of the results for research and policy.     

Associations among Adult Attachment Representations, Maternal Sensitivity, and Infant-Mother Attachment in a Sample of Adolescent Mothers

Associations among adolescent attachment organization, maternal sensitivity, and infant attachment organization were examined prospectively in 74 teenaged mother-infant dyads. Pregnant teenagers' attachment organizations predicted both sensitivity and infant-mother attachments. Mothers classified autonomous (F) in the prenatal period showed higher levels of sensitivity at both 3 and 9 months than mothers classified dismissing (Ds), preoccupied (E), or unresolved (U). Correspondence between maternal attachment (F vs. Ds/E/U) and infant attachment (secure [B] vs. avoidant [A]/resistant [C]/ disorganized [D]) was observed in 58 of 74 (78%) dyads. Exact 4-group (Ds/E/F/U and A/B/C/D) agreement was observed in 50 of 74 (68%) families. In contrast, associations between maternal sensitivity and infant attachment were not significant, leading to questions about the processes that link attachment representations, maternal behavior, and infant attachment in adolescent mothers.     

车轮扭矩传感器的结构分析

用ANSYS软件描述了有限元建模及扭矩传感器的分析 ,通常采用力传感器的应变片布片方案 .本文主要工作是建立传感器结构的弹性体的有限元模型 ,分析滚动力矩My 作用于弹性体时的应力和应变分布情况 ,并展示结果     

A study of the validity of four types of student ratings of college teaching assessed on a criterion of student achievement gains

The purpose of the study was to investigate relationships between student ratings of college teaching using four types of student rating instruments and pre- vs. post-student achievement gains in 36 sections of an undergraduate analytic geometry and calculus course. Student rating instruments used varied according to type of items (high vs. low inference) and focus (students rating their own perceived growth vs. rating the instructor). Data were collected on 799 students (66% freshmen; 16% sophomore; and 15% juniors) at the University of Florida, and relationships were analyzed using the Pearson product-moment correlation technique. Significant relationships were not found between student ratings and student achievement.     

Individual differences in inhibitory control and children's theory of mind

This research examined the relation between individual differences in inhibitory control (IC; a central component of executive functioning) and theory-of-mind (ToM) performance in preschool-age children. Across two sessions, 3- and 4-year-old children (N = 107) were given multitask batteries measuring IC and ToM. Inhibitory control was strongly related to ToM, r = .66, p < .001. This relation remained significant controlling for age, gender, verbal ability, motor sequencing, family size, and performance on pretend-action and mental state control tasks. Inhibitory tasks requiring a novel response in the face of a conflicting prepotent response (Conflict scale) and those requiring the delay of a prepotent response (Delay scale) were significantly related to ToM. The Conflict scale, however, significantly predicted ToM performance over and above the Delay scale and control measures, whereas the Delay scale was not significant in a corresponding analysis. These findings suggest that IC may be a crucial enabling factor for ToM development, possibly affecting both the emergence and expression of mental state knowledge. The implications of the findings for a variety of executive accounts of ToM are discussed.     

Writing evaluation: rater and task effects on the reliability of writing scores for children in Grades 3 and 4

We examined how raters and tasks influence measurement error in writing evaluation and how many raters and tasks are needed to reach a desirable level of .90 and .80 reliabilities for children in Grades 3 and 4. A total of 211 children (102 boys) were administered three tasks in narrative and expository genres, respectively, and their written compositions were evaluated in widely used evaluation methods for developing writers: holistic scoring, productivity, and curriculum-based writing scores. Results showed that 54 and 52% of variance in narrative and expository compositions were attributable to true individual differences in writing. Students’ scores varied largely by tasks (30.44 and 28.61% of variance), but not by raters. To reach the reliability of .90, multiple tasks and raters were needed, and for the reliability of .80, a single rater and multiple tasks were needed. These findings offer important implications about reliably evaluating children’s writing skills, given that writing is typically evaluated by a single task and a single rater in classrooms and even in some state accountability systems.