Educational Research with Real-World Data: Reducing Selection Bias with Propensity Score Analysis

Often it is infeasible or unethical to use random assignment in educational settings to study important constructs and questions. Hence, educational research often uses observational data, such as large-scale secondary data sets and state and school district data, and quasi-experimental designs. One method of reducing selection bias in estimations of treatment effects is propensity score analysis. This method reduces a large number of pretreatment covariates to a single scalar function and allows researchers to compare subjects with similar probability to receive the treatment. This article provides an introduction to propensity score analysis and stratification, an example illustrating its use, and suggestions for using propensity score analysis in educational research. Accessed 6,397 times on https://pareonline.net from December 18, 2013 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right

USDA Stakeholder Workshop on Animal Bioinformatics: Summary and Recommendations

An electronic workshop was conducted on 4 November–13 December 2002 to discuss current issues and needs in animal bioinformatics. The electronic (e-mail listserver) format was chosen to provide a relatively speedy process that is broad in scope, cost-efficient and easily accessible to all participants. Approximately 40 panelists with diverse species and discipline expertise communicated through the panel e-mail listserver. The panel included scientists from academia, industry and government, in the USA, Australia and the UK. A second ‘stakeholder’ e-mail listserver was used to obtain input from a broad audience with general interests in animal genomics. The objectives of the electronic workshop were: (a) to define priorities for animal genome database development; and (b) to recommend ways in which the USDA could provide leadership in the area of animal genome database development. E-mail messages from panelists and stakeholders are archived at http://genome.cvm.umn.edu/bioinfo/. Priorities defined for animal genome database development included: (a) data repository; (b) tools for genome analysis; (c) annotation; (d) practical application of genomic data; and (e) a biological framework for DNA sequence. A stable source of funding, such as the USDA Agricultural Research Service (ARS), was recommended to support maintenance of data repositories and data curation. Continued support for competitive grants programs within the USDA Cooperative State Research, Education and Extension Service (CSREES) was recommended for tool development and hypothesis-driven research projects in genome analysis. Additional stakeholder input will be required to continuously refine priorities and maximize the use of limited resources for animal bioinformatics within the USDA

QTL global meta-analysis: are trait determining genes clustered?

Background: A key open question in biology is if genes are physically clustered with respect to their known functions or phenotypic effects. This is of particular interest for Quantitative Trait Loci (QTL) where a QTL region could contain a number of genes that contribute to the trait being measured. Results: We observed a significant increase in gene density within QTL regions compared to non-QTL regions and/or the entire bovine genome. By grouping QTL from the Bovine QTL Viewer database into 8 categories of non-redundant regions, we have been able to analyze gene density and gene function distribution, based on Gene Ontology (GO) with relation to their location within QTL regions, outside of QTL regions and across the entire bovine genome. We identified a number of GO terms that were significantly over represented within particular QTL categories. Furthermore, select GO terms expected to be associated with the QTL category based on common biological knowledge have also proved to be significantly over represented in QTL regions. Conclusion: Our analysis provides evidence of over represented GO terms in QTL regions. This increased GO term density indicates possible clustering of gene functions within QTL regions of the bovine genome. Genes with similar functions may be grouped in specific locales and could be contributing to QTL traits. Moreover, we have identified over-represented GO terminology that from a biological standpoint, makes sense with respect to QTL category type.Hanni Salih and David L Adelso

Exploring the Limitations of Measures of Students` Socioeconomic Status (SES)

This study uses a nationally representative student dataset to explore the limitations of commonly used measures of socioeconomic status (SES). Among the identified limitations are patterns of missing data that conflate the traditional conceptualization of SES with differences in family structure that have emerged in recent years and a lack of theoretically-based guidance for how the components of SES should be combined. Using kindergarten achievement data, the study illustrates how both the observed relation between SES and achievement and the observed interaction between SES and kindergarten program would be impacted by the use of different measures of SES. This study also explores the measurement of SES within a structural equation modeling (SEM) framework, highlighting both the relevant conceptual and measurement issues. Accessed 9,241 times on https://pareonline.net from May 15, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right

A randomized trial to evaluate the course of effects of a program to prevent adolescent depressive symptoms over 12 months.

Although few prevention studies have been designed to investigate the course of prevention effects over time, it seems that the effects on depressive symptoms increase from post-intervention to 6-month follow-up but then decrease with longer lags to follow-up. Furthermore, previous prevention studies have found differential intervention effects for boys and girls without testing possible explanations for this effect. The present randomized control group study with 301 8th-grade students examined the effects of a depression prevention program from baseline until 12-month follow-up. As expected, while positive intervention effects were found on girls’ depressive symptoms, no such effects were found on boys’ depressive symptoms. Further, the positive intervention effects on girls’ depressive symptoms increased to the 6-month follow-up and remained stable through the 12-month follow-up, while depression symptoms in control-group girls increased from 6-month to 12-month follow-up. Further exploratory analyses revealed that neither baseline conduct problems nor cognitive or social knowledge of the prevention program at 12-month follow-up alone explained the sex effect. However, some limited evidence was found indicating that total knowledge (cognitive and social) might partially explain the effect but there was significant variability remaining to be explained

Associations between perceived teaching behaviors and affect in upper elementary school students.

We explored the associations between student-perceived teaching behaviors and negative affect (NA) and positive affect (PA) in upper elementary age students, both before and after controlling for perceived parenting behaviors. The Teaching Behavior Questionnaire (TBQ), the Alabama Parenting Questionnaire (APQ), and the Positive and Negative Affect Schedule for Children (PANAS-C) were completed by 777 third to fifth graders in nine elementary schools. Using two-level hierarchical linear model analyses, we found that (a) perceived instructional teaching behavior was negatively associated with NA and positively associated with PA; (b) perceived organizational behavior was not associated with either; (c) perceived socio-emotional teaching behavior was positively associated with both; (d) perceived negative teaching behavior was positively associated with NA but not associated with PA. When parenting behaviors were controlled for, the associations with NA but not with PA held up. We discuss implications of the findings for education and mental health personnel

Self-Efficacy, Intrinsic Motivation, and Academic Outcomes Among Latino Middle School Students Participating in an After-School Program

This longitudinal study examined how academic self-efficacy, intrinsic motivation, and participation in an after-school program contributed to the academic achievement of Latino middle school students over the course of one school year. Participants were 47 Latino students in sixth through eighth grades who attended two public middle schools in which an after-school program was held that was specifically for Latino students. Results from ordinary least squares regression revealed that intrinsic motivation was positively associated with students GPAs, self-efficacy was a positive predictor of students’ school attendance and standardized math achievement scores, and attendance at the after-school program also contributed positively to students’ math achievement. Results from multilevel growth modeling showed that students’ self-efficacy and intrinsic motivation remained stable across the school year and were not related to students’ degree of participation in the after-school program. Several avenues for future research within the Latino student population are discussed

A Survey for Infall Motions toward Starless Cores. II. CS(2−1)CS (2-1) and N2H+(1−0)N_2H^+ (1-0) Mapping Observations

We present the results of an extensive mapping survey of 53 `starless' cores in the optically thick line of CS 2-1 and the optically thin lines of N2H+ 1-0 and C18O 1-0. The purpose of this survey was to search for signatures of extended inward motions. This study finds 10 `strong' and 9 `probable' infall candidates, based on $\delta V_{CS}$ analysis and on the spectral shapes of CS lines. From our analysis of the blue-skewed CS spectra and the $\delta V_{CS}$ parameter, we find typical infall radii of 0.06-0.14 pc. Also, using a simple two layer radiative transfer model to fit the profiles, we derive one-dimensional infall speeds, half of whose values lie in the range of 0.05-0.09 km s$^{-1}$. These values are similar to those found in L1544 by Tafalla et al., and this result confirms that infall speeds in starless cores are generally faster than expected from ambipolar diffusion in a strongly sub-critical core. In addition, the observed infall regions are too extended to be consistent with the `inside-out' collapse model applied to a very low-mass star. In the largest cores, the spatial extent of the CS spectra with infall asymmetry is larger than the extent of the $\rm N_2H^+$ core by a factor of 2-3. All these results suggest that extended inward motions are a common feature in starless cores, and that they could represent a necessary stage in the condensation of a star-forming dense core.Comment: Two tex files for manuscript and tables, and 38 figures. To appear in ApJ

Molecular Line Profile Fitting with Analytic Radiative Transfer Models

We present a study of analytic models of starless cores whose line profiles have ``infall asymmetry,'' or blue-skewed shapes indicative of contracting motions. We compare the ability of two types of analytical radiative transfer models to reproduce the line profiles and infall speeds of centrally condensed starless cores whose infall speeds are spatially constant and range between 0 and 0.2 km s-1. The model line profiles of HCO+ (J=1-0) and HCO+ (J=3-2) are produced by a self-consistent Monte Carlo radiative transfer code. The analytic models assume that the excitation temperature in the front of the cloud is either constant (``two-layer'' model) or increases inward as a linear function of optical depth (``hill'' model). Each analytic model is matched to the line profile by rapid least-squares fitting. The blue-asymmetric line profiles with two peaks, or with a blue shifted peak and a red shifted shoulder, can be well fit by the ``HILL5'' model (a five parameter version of the hill model), with an RMS error of 0.02 km s-1. A peak signal to noise ratio of at least 30 in the molecular line observations is required for performing these analytic radiative transfer fits to the line profiles.Comment: 48 pages, 20 figures, accepted for publication in Ap

Millimeter and Submillimeter Survey of the R Corona Australis Region

Using a combination of data from the Antarctic Submillimeter Telescope and Remote Observatory (AST/RO), the Arizona Radio Observatory Kitt Peak 12m telescope and the Arizona Radio Observatory 10m Heinrich Hertz Telescope, we have studied the most active part of the R CrA molecular cloud in multiple transitions of Carbon Monoxide, HCO$^+$ and 870\micron continuum emission. Since R CrA is nearby (130 pc), we are able to obtain physical spatial resolution as high as 0.01pc over an area of 0.16 pc$^2$, with velocity resolution finer than 1 km/s. Mass estimates of the protostar driving the mm-wave emission derived from HCO$^+$, dust continuum emission and kinematic techniques point to a young, deeply embedded protostar of $\sim$0.5-0.75 M$_\odot$, with a gaseous envelope of similar mass. A molecular outflow is driven by this source that also contains at least 0.8 M$_\odot$ of molecular gas with $\sim$0.5 L$_\odot$ of mechanical luminosity. HCO$^+$ lines show the kinematic signature of infall motions as well as bulk rotation. The source is most likely a Class 0 protostellar object not yet visible at near-IR wavelengths. With the combination of spatial and spectral resolution in our data set, we are able to disentangle the effects of infall, rotation and outflow towards this young object.Comment: 29 pages, 9 figures. Accepted for publication in the Astrophysical Journa