Best Practices for English Language Learners in Massachusetts: Five Years After The Question 2 Mandate

Educating English language learners (ELLs) presents a challenge for teachers and policy makers; the population of ELLs increases, yet their achievement trails that of their native English-speaking peers. In November 2002, Massachusetts voters supported a law that mandated Sheltered English Immersion (SEI) as the primary means of instruction for ELLs, effectively ending transitional bilingual education. This report examines key considerations in educating ELLs, and in implementing SEI in Massachusetts schools. It also presents case studies of three schools making significant strides with ELLs through innovative programming built around SEI methods yet maintaining important bilingual education practices that promote educational equity. Cross-case analysis identified themes about strategic data use, staff recruitment, and supports for students and families.     

Instrumental Variables Two-Stage Least Squares (2SLS) vs. Maximum Likelihood Structural Equation Modeling of Causal Effects in Linear Regression Models

In the presence of omitted variables or similar validity threats, regression estimates are biased. Unbiased estimates (the causal effects) can be obtained in large samples by fitting instead the Instrumental Variables Regression (IVR) model. The IVR model can be estimated using structural equation modeling (SEM) software or using Econometric estimators such as two-stage least squares (2SLS). We describe 2SLS using SEM terminology, and report a simulation study in which we generated data according to a regression model in the presence of omitted variables and fitted (a) a regression model using ordinary least squares, (b) an IVR model using maximum likelihood (ML) as implemented in SEM software, and (c) an IVR model using 2SLS. Coverage rates of the causal effect using regression methods are always unacceptably low (often 0). When using the IVR model, accurate coverage is obtained across all conditions when N = 500. Even when the IVR model is misspecified, better coverage than regression is generally obtained. Differences between 2SLS and ML are small and favor 2SLS in small samples (N ≤ 100).     

Factor Analysis with Ordinal Indicators: A Monte Carlo Study Comparing DWLS and ULS Estimation

Factor analysis models with ordinal indicators are often estimated using a 3-stage procedure where the last stage involves obtaining parameter estimates by least squares from the sample polychoric correlations. A simulation study involving 324 conditions (1,000 replications per condition) was performed to compare the performance of diagonally weighted least squares (DWLS) and unweighted least squares (ULS) in the procedure's third stage. Overall, both methods provided accurate and similar results. However, ULS was found to provide more accurate and less variable parameter estimates, as well as more precise standard errors and better coverage rates. Nevertheless, convergence rates for DWLS are higher. Our recommendation is therefore to use ULS, and, in the case of nonconvergence, to use DWLS, as this method might converge when ULS does not.     

Exploring the Underlying Factor Structure of the Parent Reading Belief Inventory (PRBI): Some Caveats

Although mainstream preschool programs have been in existence since the 1970s, little is known about the ways in which typical children attempt to understand what it means for a peer to have a disability. In this study, 4-year-old children without disabilities who were enrolled in a mainstream preschool class explained their peers' disabilities by referring to concepts of immaturity, accident, or adaptive equipment to account for the behavioral differences that they observed. The implications of these cognitions for children's developing attitudes and behaviors toward peers with disabilities are discussed.     

Granite desalination using electromigration. Influence of type of granite and saline contaminant

We describe the results of electromigration desalination of two soluble salt-contaminated Galician granites. The efficacy of electromigration, which had not been previously applied to granite, was assessed for two types of granite contaminated with a 20% NaCl solution and seawater. Desalination effectiveness was evaluated as follows: (1) analysis of anode and cathode ion content during testing; (2) analysis of ions at different distances from the electrodes after testing; (3) pH assessment of the stone surfaces; and (4) evaluation of colour changes. Results were very satisfactory; by the end of testing, chloride was reduced by almost 100% in both the NaCl and seawater contaminated samples. Sulfate reduction was also significant, despite this ion's lower mobility. The granite pH values remained close to neutral and colour changes were minimal. The difference in effectiveness of the process for the two types of stone was associated with their dissimilar pore structure.     

Adaptation and evaluation of a learning analytics dashboard to improve academic support at three Latin American universities

Despite the success of academic advising dashboards in several higher educational institutions (HEI), these dashboards are still under-explored in Latin American HEI's. To close this gap, three different Latin American universities adapted an existing advising dashboard, originally deployed at the KU Leuven to their own context. In all three cases, the context was the main ruling factor to these adaptations. In this paper, we describe these adaptions using a framework that focuses on four different elements of the context: Objectives, Stakeholders, Key moment and Interactions. Evaluation of the adapted dashboards in the three different Latin American universities is conducted through pilots. This evaluation shows the value of the dashboard approach in different contexts in terms of satisfaction, usefulness and impact in academic decision-making and advising tasks. The main contribution of this paper is the systematic reporting of the adaptations to an academic advising dashboard and showing the value of an academic advising dashboard on academic decision-making and advising tasks.     

New curve sprint test for soccer players: Reliability and relationship with linear sprint

ABSTRACT

The speed performance is involved not only in linear sprints, but also in a wide spectrum of multi-directional movements, such as curve sprinting. Curved sprint can be defined as sprint with gradual and continuous change of direction (COD). Although ~85% of the actions performed at maximum velocity in a professional soccer league are curvilinear sprints, there is not any specific test to assess this ability. This study aimed to analyse the reliability of a new curve sprint test, and compare its results with those obtained by soccer players in linear sprint. Forty experienced soccer players performed 3 attempts of curve sprint (using the penalty arc) to right and left side (17 m), and 3 linear sprints (17 m) in two different days. The ICCs (inter-session reliability) were 0.93 for sprint curve right side (CSRS) and 0.89 for sprint curve left side (CSLS), considered “acceptable”. The CVs (intra-session reliability) were 0.87% in CSRS and 1.15% in CSLS. The coefficient of determination (R²) between linear and curve sprinting was ~35%. The association between curve sides was “very large” (r = 0.878; p < 0.01). In summary, we showed that “curve sprint test” is highly reliable, and that curvilinear and linear sprints are different and independent actions.     

Twenty-four-hour movement behaviours and fundamental movement skills in preschool children: A compositional and isotemporal substitution analysis

ABSTRACT

Studies that have analysed the association between the different movement behaviours and fundamental movement skills (FMS) have considered it in an independent manner, disregarding the compositional nature of 24-h movement behaviours (24-h MB). The aim of this study was to investigate the relationship between the 24-h MB and FMS in preschoolers using a compositional data analysis . Two hundred and four preschoolers (4.5 ± 0.8 years old; 101 boys) provided objectively assessed physical activity (PA) and sedentary behaviour (SB) data (Actigraph wGT3X), and FMS (TGMD-2). Sleep duration (SD) was reported by parents. Association of daily composition of movement behaviours with FMS was explored using compositional analysis and isotemporal substitution (R Core Team, 3.6.1). When considered as a 24-h MB composition (PA, SB and SD), adjusted for age, BMI and sex, the composition predicted locomotor (r² = 0.31), object control (r² = 0.19), and total motor score (r² = 0.35), respectively (all P < 0.001). Reallocation of time from light to moderate-to-vigorous PA was associated with greatest positive changes in total motor score. Achieving adequate balance between movement behaviours over the 24-h period, and its relationship with locomotor and object control skills should be considered and further investigated in early childhood.     

Computing the topology of an arrangement of implicitly defined real algebraic plane curves

We introduce a new algebraic approach dealing with the problem of computing the topology of an arrangement of a finite set of real algebraic plane curves presented implicitly. The main achievement of the presented method is a complete avoidance of irrational numbers that appear when using the sweeping method in the classical way for solving the problem at hand. Therefore, it is worth mentioning that the efficiency of the proposed method is only assured for low-degree curves.     

Evolution and Creationism: Views of Students in a Colombian University—Findings from 7 Years of Data Using a Three-Question Survey

Research in Science Education - The theory of evolution is the backbone of the biological sciences. Arguably, this is the reason why evolution education is an extensively investigated issue in...