cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
title: Quasi-Experiments in Schools: The Case for Historical Cohort Control Groups
Creators: name: Walser, Tamara M.
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: There is increased emphasis on using experimental and quasi-experimental methods to evaluate educational programs; however, educational evaluators and school leaders are often faced with challenges when implementing such designs in educational settings. Use of a historical cohort control group design provides a viable option for conducting quasi-experiments in school-based outcome evaluation. A cohort is a successive group that goes through some experience together, such as a grade level or a training program. A historical cohort comparison group is a cohort group selected from pre-treatment archival data and matched to a subsequent cohort currently receiving a treatment. Although prone to the same threats to study validity as any quasi-experiment, issues related to selection, history, and maturation can be particularly challenging. However, use of a historical cohort control group can reduce noncomparability of treatment and control conditions through local, focal matching. In addition, a historical cohort control group design can alleviate concerns about denying program access to students in order to form a control group, minimize resource requirements and disruption to school routines, and make use of archival data schools and school districts collect and find meaningful. Accessed 12,614 times on https://pareonline.net from June 23, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
Longitudinal Single-Bunch Instabilities
Creators: name: M. Migliorati
name: L. Palumbo
Publisher: name: INFN Open Access Repository
Year: 2001

description: After introducing the concepts of longitudinal wakefield and coupling impedance, we review the theory of longitudinal single-bunch collective effects in storage rings. From the Fokker-Planck equation we first derive the stationary solution describing the natural single-bunch regime, and then treat the problem of microwave instability, showing the different approaches used for estimating the threshold current.We end the lecture with the semi-empirical laws that allow us to obtain the single-bunch behavior above threshold, and with a description of the simulation codes that are now reliable tools for investigating all these effects.
Environment and Nuclear Physics: The GEDI Experiment
Creators: name: E. Bernieri
name: A. Balerna
name: A. Esposito
name: U. Denni
name: M. Chiti
name: M.A. Frani
name: V. Tullio
Publisher: name: INFN Open Access Repository
Year: 2002

description: The aim of GEDI (Gamma Emission in Deep Ice) experiment  was the realisation of a portable g-ray spectrometer for in situ radioactivity measurements on glaciers and snowfields. This kind of measurements is very useful in a wide set of environmental studies, in particular during glacial drillings for ice core studies and in pollution monitoring in high altitude or in remote areas, were sampling is difficult or impossible. In this paper the instrument realised and its performances on the field are described in detail.The results of the first measurements performed on the Appennini and Himalaya range, showing the presence in the snow of small amounts of the artificial radioisotope 137Cs, are also reported and discussed.
Orchard Park: a tenant survey of the second installment of public housing in Vancouver (December 1958-May 1960)
Creators: name: Reid, Ella Mary
Publisher: name: University of British Columbia
Year: 2011

description: The Orchard Park Housing Project, first tenanted in December 1958 is the second instalment of subsidized housing in Vancouver. Also managed by the Vancouver Housing Authority under the sanction of federal, provincial and municipal governments, it is the sister project to "Little Mountain", the public housing project situated at Main Street and 33rd Avenue, Vancouver. This project has been the subject of a previous survey (Elaine Fromson, Joy Hansen, and Roger Smith: The Little Mountain Low-Rental Housing Project: A Survey of its Welfare Aspects.) An important similarity to the Little Mountain project is that Orchard Park, too, was constructed without direct involvement with slum-clearance; in other words, the people here re-housed were drawn from many different locations to a new site. This study attempts to analyse, from the tenants’ point of view, the efficacy with which their various "welfare" needs are being met by the provision of publicly-owned housing; the ramifications of project-community relations; and the administrative implications of the entire undertaking. This information was obtained by means of interviews (a one-in-three sampling of the tenant population), averaging approximately one hour in length. Proportional samples of the tenant "categories" were obtained, with regard to (a) types of family ("complete" families, "broken" families, "single" occupants) and (b) income groups. An overall statistical picture, for comparison, was derived from the registration files of the Vancouver Housing Authority. Tenant reactions varied greatly depending partially upon previous housing experience; but the provision of new, bright, and clean surroundings, with adequate heat and hot water, was hailed with virtual unanimity. However, several areas of concern are outstanding (1) No appropriately planned facilities for children exist; (2) initial laundry arrangements were unsatisfactory; (3) the layout of Orchard Park includes three "through" streets, a hazard to both young and old; and, (4) so far as space and facilities are concerned, absolutely no provision has been made for tenant gatherings. The growing proportion of lower-income families, and also of multi-problem families in local public housing is vital in the implications of this study, which are discussed fully in Chapter IV. It is clear that not only further research, but more attention to "welfare practicalities" is essential, if present deficiencies are to be avoided in the future.
Ground-state properties of tubelike flexible polymers
Creators: name: Vogel, Thomas
name: Neuhaus, Thomas
name: Bachmann, Michael
name: Janke, Wolfhard
Publisher: name: arXiv
Year: 2010
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: In this work we investigate structural properties of native states of a simple model for short flexible homopolymers, where the steric influence of monomeric side chains is effectively introduced by a thickness constraint. This geometric constraint is implemented through the concept of the global radius of curvature and affects the conformational topology of ground-state structures. A systematic analysis allows for a thickness-dependent classification of the dominant ground-state topologies. It turns out that helical structures, strands, rings, and coils are natural, intrinsic geometries of such tubelike objects.
A honvédelmi jog és igazgatás kutatásának lehetséges hosszú távú irányai az eddigi kutatási eredmények tükrében
Creators: name: Farkas, Ádám
name: Hornyacsek, Júlia
Publisher: name: Magyar Hadtudományi Társaság
Year: 2018

description: Hadtudomány, vol. 28. Electronic issue., ISSN 1215-4121, eISSN 1588-0605
Star Formation in the Central 400 pc of the Milky Way: Evidence for a Population of Massive YSOs
Creators: name: Yusef-Zadeh, F.
name: Hewitt, J. W.
name: Arendt, R. G.
name: Whitney, B.
name: Rieke, G.
name: Wardle, M.
name: Hinz, J. L.
name: Stolovy, S.
name: Lang, C. C.
name: Burton, M. G.
name: Ramirez, S.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The central kpc of the Milky Way might be expected to differ significantly from the rest of the Galaxy with regard to gas dynamics and the formation of YSOs. We probe this possibility with mid-infrared observations obtained with IRAC and MIPS on Spitzer and with MSX. We use color-color diagrams and SED fits to explore the nature of YSO candidates (including objects with 4.5 micron excesses possibly due to molecular emission). There is an asymmetry in the distribution of the candidate YSOs, which tend to be found at negative Galactic longitudes; this behavior contrasts with that of the molecular gas, approximately 2/3 of which is at positive longitudes. The small scale height of these objects suggests that they are within the Galactic center region and are dynamically young. They lie between two layers of infrared dark clouds and may have originated from these clouds. We identify new sites for this recent star formation. The methanol masers appear to be associated with young, embedded YSOs characterized by 4.5 micron excesses. We use the SEDs of these sources to estimate their physical characteristics. Within the central 400x50 pc (|l|<1.3\degr and |b|<10') the star formation rate based on the identification of Stage I evolutionary phase of YSO candidates is about 0.14 solar mass/yr. We suggest that a recent burst of star formation took place within the last 10^5 years. This suggestion is also consistent with estimates of star formation rates within the last ~10^7 years showing a peak around 10^5 years ago. Lastly, we find that the Schmidt-Kennicutt Law applies well in the central 400 pc of the Galaxy. This implies that star formation does not appear to be dramatically affected by the extreme physical conditions in the Galactic center region.
description: 96 pages, ten tables, 35 figures, ApJ (in press), replaced by a revised version
Kinematical Constraints, Factorization and Kinematical Zeros, I
Creators: name: P. Di-Vecchia
name: F. Drago
name: M. L. Paciello
Publisher: name: INFN Open Access Repository
Year: 1968

description: The kinematical constraints at t = 0 are derived for an important class of reactions. The factorization requirements for the Regge pole residue functions are studied. The 'minimal' behaviour at t = 0 of the Regge residue functions, consistent with the kinematical constraints and the factorization, is given. The results are compared with those obtained in the group theoretical approach.
On Baryon Number Non-Conservation in Two-Dimensional O(2N+1) QCD
Creators: name: Friedmann, Tamar
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We construct a classical dynamical system whose phase space is a certain infinite-dimensional Grassmannian manifold, and propose that it is equivalent to the large N limit of two-dimensional QCD with an O(2N+1) gauge group. In this theory, we find that baryon number is a topological quantity that is conserved only modulo 2. We also relate this theory to the master field approach to matrix models.
description: 22 pages. Accepted for publication in Int. J. Mod. Phys. A
title: Estimating unbiased treatment effects in education using a regression discontinuity design
Creators: name: Smith, William C.
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: The ability of regression discontinuity (RD) designs to provide an unbiased treatment effect while overcoming the ethical concerns plagued by Random Control Trials (RCTs) make it a valuable and useful approach in education evaluation. RD is the only explicitly recognized quasi-experimental approach identified by the Institute of Education Statistics to meet the prerequisites of a causal relationship. Unfortunately, the statistical complexity of the RD design has limited its application in education research. This article provides a less technical introduction to RD for education researchers and practitioners. Using visual analysis to aide conceptual understanding, the article walks readers through the essential steps of a Sharp RD design using hypothetical, but realistic, district intervention data and provides additional resources for further exploration. Accessed 7,566 times on https://pareonline.net from August 03, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
Nucleosynthesis in Two-Dimensional Delayed Detonation Models of Type Ia Supernova Explosions
Creators: name: Maeda, K.
name: Roepke, F. K.
name: Fink, M.
name: Hillebrandt, W.
name: Travaglio, C.
name: Thielemann, F. -K.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The nucleosynthetic characteristics of various explosion mechanisms of Type Ia supernovae (SNe Ia) is explored based on three two-dimensional explosion simulations representing extreme cases: a pure turbulent deflagration, a delayed detonation following an approximately spherical ignition of the initial deflagration, and a delayed detonation arising from a highly asymmetric deflagration ignition. Apart from this initial condition, the deflagration stage is treated in a parameter-free approach. The detonation is initiated when the turbulent burning enters the distributed burning regime. This occurs at densities around $10^{7}$ g cm$^{-3}$ -- relatively low as compared to existing nucleosynthesis studies for one-dimensional spherically symmetric models. The burning in these multidimensional models is different from that in one-dimensional simulations as the detonation wave propagates both into unburned material in the high density region near the center of a white dwarf and into the low density region near the surface. Thus, the resulting yield is a mixture of different explosive burning products, from carbon-burning products at low densities to complete silicon-burning products at the highest densities, as well as electron-capture products synthesized at the deflagration stage. In contrast to the deflagration model, the delayed detonations produce a characteristic layered structure and the yields largely satisfy constraints from Galactic chemical evolution. In the asymmetric delayed detonation model, the region filled with electron capture species (e.g., $^{58}$Ni, $^{54}$Fe) is within a shell, showing a large off-set, above the bulk of $^{56}$Ni distribution, while species produced by the detonation are distributed more spherically (abridged).
description: Accepted by the Astrophysical Journal. 15 pages, 14 figures, 4 tables
title: Sample Size Determination for Regression Models Using Monte Carlo Methods in R
Creators: name: Beaujean, A. Alexander
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: A common question asked by researchers using regression models is, What sample size is needed for my study? While there are formulae to estimate sample sizes, their assumptions are often not met in the collected data. A more realistic approach to sample size determination requires more information such as the model of interest, strength of the relations among the variables, and any data quirks (e.g., missing data, variable distributions, variable reliability). Such information can only be incorporated into sample size determination methods that use Monte Carlo (MC) methods. The purpose of this article is to demonstrate how to use a MC study to decide on sample size for a regression analysis using both power and parameter accuracy perspectives. Using multiple regression examples with and without data quirks, I demonstrate the MC analyses with the R statistical programming language. Accessed 22,856 times on https://pareonline.net from August 23, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
title: Impact of Violation of the Missing-at-Random Assumption on Full-Information Maximum Likelihood Method in Multidimensional Adaptive Testing
Creators: name: Han, Kyung T.
name: Guo, Fanmin
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: The full-information maximum likelihood (FIML) method makes it possible to estimate and analyze structural equation models (SEM) even when data are partially missing, enabling incomplete data to contribute to model estimation. The cornerstone of FIML is the missing-at-random (MAR) assumption. In (unidimensional) computerized adaptive testing (CAT), unselected items (i.e., responses that are not observed) remain at random even though selected items (i.e., responses that are observed) have been associated with a test takerâ€™s latent trait that is being measured. In multidimensional adaptive testing (MAT), however, the missingness in the response data partially depends on the unobserved data because items are selected based on various types of information including the covariance among latent traits. This eventually may lead to violations of MAR. This study aimed to evaluate the potential impact such a violation of MAR in MAT could have on FIML estimation performance. The results showed an increase in estimation errors in item parameter estimation when the MAT response data were used, and differences in the level of the impact depending on how items loaded on multiple latent traits. Accessed 4,728 times on https://pareonline.net from May 19, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
title: Altered proteolytic and amydolytic activity in insecticide-susceptible and -resistant strains of the maize weevil, Sitophilus zeamais
Creators: name: Silva, L. B.
name: Lopes, K. V. G.
name: Oliveira, M. G. A.
name: Guedes, R. N. C.
Publisher: name: Julius Kühn-Institut
Year: 2010
Subjects: subject: fitness cost mitigation
subject: insecticide resistance
subject: digestive enzymes
subject: amylases
subject: proteinases

description: Julius-Kühn-Archiv; 425; 845-850
title: A Comparison of Three Conditional Growth Percentile Methods: Student Growth Percentiles, Percentile Rank Residuals, and a Matching Method
Creators: name: Wyse, Adam E.
name: Seo, Dong Gi
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: This article provides a brief overview and comparison of three conditional growth percentile methods; student growth percentiles, percentile rank residuals, and a nonparametric matching method. These approaches seek to describe student growth in terms of the relative percentile ranking of a student in relationship to students that had the same profile of prior achievement. It is shown that even though the methods come from a similar conceptual foundation, the methods make different assumptions and use different models to estimate growth percentiles. Reading and Mathematics data from a large-scale assessment program are used to compare the growth percentile estimates in a practical setting. Results suggested that the methods often give somewhat similar results. However, the matching method tended to provide somewhat different estimates compared to the other approaches for students that had extreme scores on the prior year test. The implications of these results for large-scale state accountability programs are discussed. Accessed 5,254 times on https://pareonline.net from November 12, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
Churches and welfare services in Richmond, British Columbia : a survey of reciprocal awareness and utilization
Creators: name: Stalwick, Harvey Noel
Publisher: name: University of British Columbia
Year: 2011

description: In the complexity of contemporary society, the welfare of individuals is dependent upon the co-operation of the helping professions and co-ordination of services provided by the many social institutions. This study considered the degree of cooperation between the two helping professions, social work and the ministry, in the suburban community of Richmond, British Columbia. The research method in this qualitative study included interviews with fifteen clergymen and ten social workers in order to apply the concepts of reciprocal awareness and utilization. This method facilitated evaluation of the knowledge one profession had of the other's role and function, and the extent to which this knowledge was used for the benefit of the population they served. Supplementing this main method was a brief historical consideration of the impact of industrialization on the development and contemporary role of the church and social welfare. The findings of the study showed the awareness one profession had of the other was based more on general knowledge than direct interprofessional contact. The utilization of each other's resources, as indicated by referral patterns, was minimal and typically the result of coincidence rather than planning. Reciprocity, the main concept evaluated, was virtually non-existent. This can primarily be accounted for by absence of communication, despite an acknowledgement by both professions, particularly social work, that there were several gains to be realized from more co-operation.
title: Revising an Engineering Design Rubric: A Case Study Illustrating Principles and Practices to Ensure Technical Quality of Rubrics
Creators: name: Goldberg, Gail Lynn
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: This article provides a detailed account of a rubric revision process to address seven common problems to which rubrics are prone: lack of consistency and parallelism; the presence of â€œorphanâ€ and â€œwidowâ€ words and phrases; redundancy in descriptors; inconsistency in the focus of qualifiers; limited routes to partial credit; unevenness in incremental levels of performance; and inconsistencies across suites or sets of related rubrics. The author uses examples from both the draft stage precursor and the first revised (pilot) version of the Engineering Design Process Portfolio Scoring Rubric (EDPPSR), to illustrate the application of broadly relevant guidelines that can inform the creation of a newâ€”or revision of an existingâ€”rubric to achieve technical quality while preserving content integrity Accessed 6,281 times on https://pareonline.net from August 02, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
title: Analyzing Group Level Effects with Clustered Data Using Taylor Series Linearization
Creators: name: Huang, Francis L.
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: Clustered data (e.g., students within schools) are often analyzed in educational research where data are naturally nested. As a consequence, multilevel modeling (MLM) has commonly been used to study the contextual or group-level (e.g., school) effects on individual outcomes. The current study investigates the use of an alternative procedure to MLM: regression using Taylor series linearization (TSL) variance estimation. Despite the name, regressions using TSL are straightforward to conduct, can yield consistent and unbiased estimates and standard errors (given the appropriate conditions), and can be performed using a variety of commercially- and freely-available statistical software. I analyze a subsample of the High School and Beyond (HSB) dataset using MLM, regression using TSL, and ordinary least squares regression and compare results. In addition, 12,000 random samples are drawn from the HSB dataset of varying level-one and level-two sample sizes in order to compute biases in standard errors based on the different conditions. Sample R and SAS syntax showing how to run regressions using TSL are provided Accessed 5,000 times on https://pareonline.net from November 11, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
Additional file 3 of Identification of ferroptosis related biomarkers and immune infiltration in Parkinson’s disease by integrated bioinformatic analysis
Creators: name: Xing, Na
name: Dong, Ziye
name: Wu, Qiaoli
name: Zhang, Yufeng
name: Kan, Pengcheng
name: Han, Yuan
name: Cheng, Xiuli
name: Wang, Yaru
name: Zhang, Biao
Publisher: name: figshare
Year: 2023
Subjects: subject: Space Science
subject: Medicine
subject: Immunology
subject: FOS: Clinical medicine
subject: Biological Sciences not elsewhere classified

description: Supplementary Material 3
Stationary waves in a supersonic flow of a two-component Bose gas
Creators: name: Kravchenko, L. Yu.
name: Fil, D. V.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: A stationary wave pattern occurring in a flow of a two-component Bose-Einstein condensate past an obstacle is studied. We consider the general case of unequal velocities of two superfluid components. The Landau criterium applied to the two-component system determines a certain region in the velocity space in which superfluidity may take place. Stationary waves arise out of this region, but under the additional condition that the relative velocity of the components does not exceed some critical value. Under increase of the relative velocity the spectrum of the excitations becomes complex valued and the stationary wave pattern is broken. In case of equal velocities two sets of stationary waves that correspond to the lower and the upper Bogolyubov mode can arise. If one component flows and the other is at rest only one set of waves may emerge. Two or even three interfere sets of waves may arise if the velocities approximately of equal value and the angle between the velocities is close to pi/2. In two latter cases the stationary waves correspond to the lower mode and the densities of the components oscillate out-of-phase. The ratio of amplitudes of the components in the stationary waves is computed. This quantity depends on the relative velocity, is different for different sets of waves, and varies along the crests of the waves. For the cases where two or three waves interfere the density images are obtained.
description: 12 pages, 8 figures
Origin of magnetic moments in defective TiO2 single crystals
Creators: name: Zhou, Shengqiang
name: Cizmar, E.
name: Potzger, K.
name: Krause, M.
name: Talut, G.
name: Helm, M.
name: Fassbender, J.
name: Zvyagin, S. A.
name: Wosnitza, J.
name: Schmidt, H.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: In this paper we show that ferromagnetism can be induced in pure TiO2 single crystals by oxygen ion irradiation. By combining x-ray diffraction, Raman-scattering, and electron spin resonance spectroscopy, a defect complex, \emph{i.e.} Ti$^{3+}$ ions on the substitutional sites accompanied by oxygen vacancies, has been identified in irradiated TiO2. This kind of defect complex results in a local (TiO$_{6-x}$) stretching Raman mode. We elucidate that Ti$^{3+}$ ions with one unpaired 3d electron provide the local magnetic moments.
description: 4 pages, 4 figures, to be published at Phys. Rev. B
POSSIBILITIES OF PHYSICAL EDUCATION MEANS IN THE FORMATION OF VOLITIONAL QUALITIES IN SCHOOLCHILDREN
Creators: name: Rakhimkulov Karimzhan Datkaevich  professor of the Department of Physical Culture and Sports,  Uzbekistan State University of World Languages
Publisher: name: Zenodo
Year: 2024

description: The article examines the essence and structure of physical education means used in the author's dissertation research, the possibilities of these means, their manifestation in adolescence and the peculiarities of their formation. The methods of using a complex program in the formation of volitional qualities, the importance of exercises in the formation of volitional qualities, as well as the methods used in the formation of such qualities in schoolchildren as overcoming various difficulties in the learning process are analyzed.

Key words: volitional qualities, possibilities of physical education, formation of volitional qualities, means of physical education
title: Exploring the Limitations of Measures of Students` Socioeconomic Status (SES)
Creators: name: Dickinson, Emily R.
name: Adelson, Jill L.
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: 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.
Soliton Spheres
Creators: name: Bohle, Christoph
name: Peters, G. Paul
Publisher: name: arXiv
Year: 2009
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 53C42 (Primary) 53A30, 37K25 (Secondary)

description: Soliton spheres are immersed 2-spheres in the conformal 4-sphere S^4=HP^1 that allow rational, conformal parametrizations f:CP^1->HP^1 obtained via twistor projection and dualization from rational curves in CP^{2n+1}. Soliton spheres can be characterized as the case of equality in the quaternionic Pluecker estimate. A special class of soliton spheres introduced by Taimanov are immersions into R^3 with rotationally symmetric Weierstrass potentials that are related to solitons of the mKdV-equation via the ZS-AKNS linear problem. We show that Willmore spheres and Bryant spheres with smooth ends are further examples of soliton spheres. The possible values of the Willmore energy for soliton spheres in the 3-sphere are proven to be W=4pi*d with d a positive integer but not 2,3,5, or 7. The same quantization was previously known individually for each of the three special classes of soliton spheres mentioned above.
description: 49 pages, 43 figures
Stratigraphy of the Lower Rocky Mountain Supergroup in the Southern Canadian Rocky Mountains
Creators: name: Scott, Darcy Lon
Publisher: name: University of British Columbia
Year: 2011

description: The lower Rocky Mountain Supergroup of Pennsylvanian age contains five formations which in ascending order are: Todhunter, Tyrwhitt, Storelk, Tobermory and Kananaskis. All except the Kananaskis are new formations that are equivalent to the Tunnel Mountain Formation. The Todhunter, Tyrwhitt and Tobermory consist mainly of brown weathering, dolomitic and quartzitic, very fine- to fine-grained, pure, quartz-chert sandstones with some interbedded, locally f ossiliferous, sandy dolomite. The Storelk is quartzitic, very fine- to medium-grained, very massive, cross-bedded, white wheathering quartzi-chert sandstone. All these formations contain varying amounts of scattered medium and coarse sand. The Kananaskis consists of sandy and cherty, dense, microcrystalline, grey dolomite. The Todhunter, Tyrwhitt and Storelk Formations are interpreted as being Early Pennsylvanian (Morrowan) in age, and the Tobermory and Kananaskis Formation, which regionally may be facies equivalents, as early Middle Pennsylvanian (Atokan) in age. The contact between the lower Rocky Mountain and the underlying Etherington Formation (Late Mississippian Chesterian) is conformable and locally gradational. Contacts between the Todhunter and Tyrwhitt, and between the Storelk and Tobernory are unconformable, whereas that between the Tyrwhitt and Storelk may be conformable or unconformable. The lower Rocky Mountain is unconformably overlain by Permian, Triassic or Jurassic strata. The lower Rocky Mountain sediments were deposited in a structural basin which may have been partially isolated from adjacent basins to the north, west and south by low barrier arches. Individual formations in the succession thin in a northwesterly and southwesterly direction towards the basin flanks, where as little as 160 feet of the five formations was deposited and remains, whereas at least 1,175 feet of equivalent strata is preserved in the central part. The quartz sand was probably transported by rivers and longshore marine currents from a source lying to the east within the continental interior. Chert and phosphorite fragments ranging up to pebble size were probably locally derived. The strata of Chesterian and Morrowan age represent a regressive sequence. After Morrowan time, gentle warping, emergence, and erosion caused truncation of Lower PennsyIvanian and Upper Mississippian strata towards the east. Angular truncation, and local conglomerates composed of chert, phosphorite, sandstone and dolmite granules and pebbles mark this unconformity. Strata of Atokan age thicken westward and represent a transgressive, sequence which onlaps and truncates the underlying strata. The Pennsylvanian sandstones are a potential source of pure silica sand.
title: Editorial Changes and Item Performance: Implications for Calibration and Pretesting
Creators: name: Stoffel, Heather
name: Raymond, Mark R.
name: Bucak, S. Deniz
name: Haist, Steven A.
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: Previous research on the impact of text and formatting changes on test-item performance has produced mixed results. This matter is important because it is generally acknowledged that any change to an item requires that it be recalibrated. The present study investigated the effects of seven classes of stylistic changes on item difficulty, discrimination, and response time for a subset of 65 items that make up a standardized test for physician licensure completed by 31,918 examinees in 2012. One of two versions of each item (original or revised) was randomly assigned to examinees such that each examinee saw only two experimental items, with each item being administered to approximately 480 examinees. The stylistic changes had little or no effect on item difficulty or discrimination; however, one class of edits â€“ changing an item from an open lead-in (incomplete statement) to a closed lead-in (direct question) â€“ did result in slightly longer response times. Data for nonnative speakers of English were analyzed separately with nearly identical results. These findings have implications for the conventional practice of repretesting (or recalibrating) items that have been subjected to minor editorial changes. Accessed 3,791 times on https://pareonline.net from November 11, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
title: Using meta-regression to explore moderating effects in surveys of international achievement
Creators: name: Benton, Tom
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: This article demonstrates how meta-analytic techniques, that have typically been used to synthesize findings across numerous studies, can also be applied to examine the reasons why relationships between background characteristics and outcomes may vary across different locations in a single multi-site survey. This application is particularly relevant to the analysis of data from international surveys of student achievement. A brief introduction to the method of meta-regression is provided and the technique is demonstrated in an analysis of the extent to which the relationship between school autonomy and achievement varies depending upon the level of accountability in a country. The results show that the meta-regression approach to analysis is more accurate than combining data across all countries into a single simple model. Accessed 6,555 times on https://pareonline.net from May 19, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
Spectral shifts in the properties of a periodic multilayered stack due to isotropic chiral layers
Creators: name: Ramakrishna, S. Anantha
name: Lakhtakia, Akhlesh
Publisher: name: arXiv
Year: 2009
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Investigating the canonical problem of a periodic multilayered stack containing isotropic chiral layers, we homogenized it as a uniaxial bianisotropic medium and derived its effective constitutive parameters. The stack shows a resonant behavior, when its unit cell consists of a metallic layer and an isotropic chiral layer. The presence of isotropic chirality can result in small shifts of the resonance frequency for reasonably large values of the chirality parameter, implying that the sign of an effective permittivity can be switched. Such spectral shifts in the dielectric properties can be potentially useful for spectroscopic purposes.
description: accepted for publication in J Opt A
title: A Step-by-Step Guide to Propensity Score Matching in R
Creators: name: Randolph, Justus J.
name: Falbe, Kristina
name: Manuel, Austin Kureethara
name: Balloun, Joseph L.
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: Propensity score matching is a statistical technique in which a treatment case is matched with one or more control cases based on each caseâ€™s propensity score. This matching can help strengthen causal arguments in quasi-experimental and observational studies by reducing selection bias. In this article we concentrate on how to conduct propensity score matching using an example from the field of education. Our goal is to provide information that will bring propensity score matching within the reach of research and evaluation practitioners. Accessed 57,198 times on https://pareonline.net from November 19, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
'EUV Waves' are Waves: First Quadrature Observations of an EUV Wave from STEREO
Creators: name: Patsourakos, S.
name: Vourlidas, A.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The nature of CME-associated low corona propagating disturbances, 'EUV waves', has been controversial since their discovery by EIT on \textit{SOHO}. The low cadence, single viewpoint EUV images and the lack of simultaneous inner corona white light observations has hindered the resolution of the debate on whether they are true waves or just projections of the expanding CME. The operation of the twin EUV imagers and inner corona coronagraphs aboard \textsl{STEREO} has improved the situation dramatically. During early 2009, the \textsl{STEREO} Ahead (STA) and Behind (STB) spacecraft observed the Sun in quadrature having an $\approx 90^\circ$ angular separation. An EUV wave and CME erupted from active region 11012, on February 13, when the region was exactly at the limb for STA and hence at disk center for STB. The \textit{STEREO} observations capture the development of a CME and its accompanying EUV wave not only with high cadence but also in quadrature. The resulting unprecentented dataset allowed us to separate the CME structures from the EUV wave signatures and to determine without doubt the true nature of the wave. It is a fast-mode MHD wave after all!
description: ApJL, 2009, submitted
title: Improving Your Exploratory Factor Analysis for Ordinal Data: A Demonstration Using FACTOR
Creators: name: Baglin, James
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: Exploratory factor analysis (EFA) methods are used extensively in the field of assessment and evaluation. Due to EFAâ€™s widespread use, common methods and practices have come under close scrutiny. A substantial body of literature has been compiled highlighting problems with many of the methods and practices used in EFA, and, in response, many guidelines have been proposed with the aim to improve application. Unfortunately, implementing recommended EFA practices has been restricted by the range of options available in commercial statistical packages and, perhaps, due to an absence of clear, practical â€˜how-toâ€™ demonstrations. Consequently, this article describes the application of methods recommended to get the most out of your EFA. The article focuses on dealing with the common situation of analysing ordinal data as derived from Likert-type scales. These methods are demonstrated using the free, stand-alone, easy-to-use and powerful EFA package FACTOR (http://psico.fcep.urv.es/utilitats/factor/, Lorenzo-Seva & Ferrando, 2006). The demonstration applies the recommended techniques using an accompanying dataset, based on the Big 5 personality test. The outcomes obtained by the EFA using the recommended procedures through FACTOR are compared to the default techniques currently available in SPSS. Accessed 23,681 times on https://pareonline.net from June 14, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
Reaction under vacancy-assisted diffusion at high quencher concentration
Creators: name: Seki, Kazuhiko
name: Tachiya, M.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Theory of diffusion-mediated reactions is already established for the target problem in the dilute limit, where the immobile target is surrounded by many quenchers. For lattice random walks in the crowded situation, each quencher is surrounded by other quenchers differently. As a result, each quencher migrates differently in the presence of site blocking effects. However, in the conventional theory, such difference is ignored and quenchers are assumed to move independently of each other. In this paper, theory of diffusion-mediated reactions of target problem is developed by taking into account the site blocking effects for quencher migration and the difference in the configuration of quenchers around each quencher. Our result interpolates between those in high and low limits of quencher concentrations and is a lower bound of the survival probability. In the static limit, the exact result is reproduced for a localized sink. In the presence of diffusion, the approximation is better when intrinsic reaction rates are low.
title: Influences of mood on academic course evaluations
Creators: name: Zumbach, Joerg
name: Funke, Joachim
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: In two subsequent experiments, the influence of mood on academic course evaluation is examined. By means of facial feedback, either a positive or a negative mood was induced while students were completing a course evaluation questionnaire during lectures. Results from both studies reveal that a positive mood leads to better ratings of different dimensions of lecture quality. While in Study 1 (N=109) mood was not directly controlled, Study 2 (N=64) replicates the findings of the prior study and reveals direct influences of positive and negative mood on academic course evaluation. Accessed 5,961 times on https://pareonline.net from May 21, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
title: A Simulation Study of Missing Data with Multiple Missing X’s
Creators: name: Rubright, Jonathan D.
name: Nandakumar, Ratna
name: Gluttin, Joseph J.
Publisher: name: University of Massachusetts Amherst
Year: 2014

description: When exploring missing data techniques in a realistic scenario, the current literature is limited: most studies only consider consequences with data missing on a single variable. This simulation study compares the relative bias of two commonly used missing data techniques when data are missing on more than one variable. Factors varied include type of missingness (MCAR, MAR), degree of missingness (10%, 25%, and 50%), and where missingness occurs (one predictor, two predictors, or two predictors with overlap). Using a real dataset, cells are systematically deleted to create various scenarios of missingness so that parameter estimates from listwise deletion and multiple imputation may be compared to the "true" estimates from the full dataset. Results suggest the multiple imputation works well, even when the imputation model itself is missing data. Accessed 7,222 times on https://pareonline.net from August 12, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.
QUANTITATIVE ANALYSIS OF THE IMPACTS OF CARBON PRICING ON ENERGY INFLATION IN THE EUROPEAN UNION
Creators: name: Safonov, Mikhail
Publisher: name: University of Chicago
Year: 2023
Subjects: subject: carbon pricing
subject: electricity prices
subject: EU ETS
subject: European Union
subject: energy inflation
subject: carbon emissions

description: The aim of this paper is to quantitatively analyze the relationships between carbon prices and energy inflation. We look at the history of carbon prices in the European Union Emissions Trading Scheme (EU ETS) and different measures of energy inflation throughout the history of the EU ETS in order to analyze the transformation of their relationship through time. Our hypothesis is that the inflationary effects of carbon pricing have increased in magnitude and significance with time, with most of the pressure being put on the producers. We expect the relationship between carbon prices and producer prices to be direct. First, we look at industrial and electricity prices collected semiannually and the corresponding carbon price data. After controlling for GDP and Gas Prices we find no statistically significant relationship between carbon prices and industrial electricity prices, but an inverse relationship between carbon prices and household electricity prices. Then we looked at the bigger sample of energy inflation measures. Specifically, monthly collected Energy PPI and ICP (Producer Price Index and Index of Consumer Prices) were regressed on the carbon prices data. Now we conducted separate analyses for each of the four stages of the EU ETS’s development. Results show a strongly significant inverse relationship between ICP and carbon prices in the earliest phase and a direct relationship between PPI and carbon prices in the latest phase of development. These results support our hypothesis but bring more context to the discussion table. While the first step could not reveal any relationship between carbon prices and the producer prices as we predicted, this result is understandable after taking into account the next analysis which shows that only the latest period was significant. The inverse relationship between carbon prices is however a consistent result that is rather unintuitive. The explanation for it is likely in the fact that consumer electricity prices in the EU are under stricter regulations, and early after EU ETS’s introduction the following policy changes could be associated with a negative movement in consumer electricity prices despite the carbon prices’ growth.