Grade Retention and School Performance: An Extended Investigation

This study extends Reynolds’ (1992) investigation of the social- psychological influences on grade retention and school adjustment in early childhood by tracing the predictors and consequences of grade retention for school achievement, perceived competence, and delinquency in early adolescence (age 14). The study sample included 1,164 (93 percent of the sample from the original study) low-income, mostly black children in the Chicago Longitudinal Study. Twenty-eight percent of the study sample were retained-in-grade by age 14 (first grade to eighth grade). The strongest predictors of retention were early school performance (test scores and grades), sex (boys were more likely to be retained), parent participation in school, and school mobility. Overall, grade retention was significantly associated with lower reading and math achievement at age 14 above and beyond a comprehensive set of explanatory variables. Results based on same-age comparison groups yielded larger effects of retention on school achievement than those based on same-grade comparisons, but both approaches indicated that grade retention was associated with significantly lower reading achievement. In the full model, grade retention was unrelated to perceived school competence at age 12 and to delinquency infractions at age 14. With the exception of reading achievement, retention during the primary grades and retention during grades 4 to 7 yielded a similar pattern of effects. Findings were largely consistent with the earlier study and suggest that intervention approaches other than grade retention are needed to better promote school achievement and adjustment.

Exact Partition Function and Boundary State of 2-D Massive Ising Field Theory with Boundary Magnetic Field

We compute the exact partition function, the universal ground state degeneracy and boundary state of the 2-D Ising model with boundary magnetic field at off-critical temperatures. The model has a domain that exhibits states localized near the boundaries. We study this domain of boundary bound state and derive exact expressions for the ``$g$ function'' and boundary state for all temperatures and boundary magnetic fields. In the massless limit we recover the boundary renormalization group flow between the conformally invariant free and fixed boundary conditions.Comment: plain latex, 17 pages plus 11 figures in 3 .ps files, uuencoded in isfig.u

RNNs Implicitly Implement Tensor Product Representations

Recurrent neural networks (RNNs) can learn continuous vector representations of symbolic structures such as sequences and sentences; these representations often exhibit linear regularities (analogies). Such regularities motivate our hypothesis that RNNs that show such regularities implicitly compile symbolic structures into tensor product representations (TPRs; Smolensky, 1990), which additively combine tensor products of vectors representing roles (e.g., sequence positions) and vectors representing fillers (e.g., particular words). To test this hypothesis, we introduce Tensor Product Decomposition Networks (TPDNs), which use TPRs to approximate existing vector representations. We demonstrate using synthetic data that TPDNs can successfully approximate linear and tree-based RNN autoencoder representations, suggesting that these representations exhibit interpretable compositional structure; we explore the settings that lead RNNs to induce such structure-sensitive representations. By contrast, further TPDN experiments show that the representations of four models trained to encode naturally-occurring sentences can be largely approximated with a bag of words, with only marginal improvements from more sophisticated structures. We conclude that TPDNs provide a powerful method for interpreting vector representations, and that standard RNNs can induce compositional sequence representations that are remarkably well approximated by TPRs; at the same time, existing training tasks for sentence representation learning may not be sufficient for inducing robust structural representations.Comment: Accepted to ICLR 201

Non-scale-invariant inverse curvature flows in Euclidean space

We consider the inverse curvature flows $\dot x=F^{-p}\nu$ of closed star-shaped hypersurfaces in Euclidean space in case $0<p\not=1$ and prove that the flow exists for all time and converges to infinity, if $0<p<1$, while in case $p>1$, the flow blows up in finite time, and where we assume the initial hypersurface to be strictly convex. In both cases the properly rescaled flows converge to the unit sphere.Comment: 21 pages, this is the published versio

Gen Z and Digital Distractions in the Classroom: Student Classroom Use of Digital Devices for Non-Class Related Purposes

A 2019 survey of college students examined classroom-learning distractions caused by their use of digital devices for non-class purposes. The purpose of the survey, part of an on-going study, was to learn more about students’ behaviors and perceptions regarding their classroom uses of digital devices for non-class purposes. The survey included 986 respondents in 37 U.S. states and 47 respondents in Alberta, Canada. A significant feature of the study was its measurement of frequency and duration of students’ classroom digital distractions as well as respondents’ motivations for engaging in the distracting behavior. Respondents averaged 19.4% of class time using a digital device for non-class purposes. The average respondent used a digital device 9.06 times during a typical school day in the 2019 survey for non-class purposes. On a weighted average, survey respondents indicated they would turn-off all non-class digital distractions if their instructor gave them 7.8% extra credit on their final class grade

Touch down in Pittsburghese

In standard American English, down may take a DP object only if the DP indicates a path, as in I walked down the street. However, for some speakers of Pittsburgh English, it is also grammatical for down to take a DP object indicating a location or goal, as in She works down Baltimore (meaning ‘She works down in Baltimore’). In this work, I describe the distributional properties of this usage, which I name “touch down.” Based on these properties, I propose the syntactic analysis that touch down licenses a silent preposition where standard American English has an overt preposition, and that this silent preposition incorporates into down