bluuebunny/crossref_metadata_2025 huggingface dataset:
Mobile telephone use effects on perception of verticality
Authors: Bamiou Doris‐Eva , Ceranic Borka , Vickers Deborah , Zamyslowska‐Szmytke Ewa , Cox Robin , Chadwick Philip , Luxon Linda M
Published: September 2014

Low‐level radiofrequency (RF) signals may produce disorientation and nausea. In experiment I, we assessed mobile phone effects on graviception in nine symptomatic subjects after mobile telephone use and 21 controls. The mobile handset was strapped to each ear for 30 min in pulsed emission, continuous RF emission, or no emission test mode, respectively. The subjective visual vertical and horizontal (SVV/SVH) were tested from min 25 of exposure. There was no exposure effect; however, there was an ear effect, with the SVV/SVH being shifted to the opposite direction of the ear exposed. This could be due to thermal or RF effects or handset weight. In experiment II, we assessed the handset weight effect on 18 normal controls. After baseline SVV/SVH, the switched off handset was strapped to either ear; the SVV/SVH was repeated 25 min later. A significant ear effect was found. We compared the observed ear effect SVV/SVH change in the experiment II group to the continuous exposure ear effect change in the experiment I group, and the difference was not significant. The ear effect was attributed to a minor head tilt due to the handset weight, or proprioceptive stimulation of neck muscle affecting the perception of verticality. Bioelectromagnetics. 35:27–34, 2015. © 2014 Wiley Periodicals, Inc.
Acid–Base Cooperative Catalysis over Mesoporous Nitrogen‐Rich Carbon
Authors: Goyal Reena , Sarkar Bipul , Lucus Nishita , Bordoloi Ankur
Published: September 2014

WOx nanoclusters (2–3 nm) embedded on a mesoporous nitrogen‐rich carbon material were synthesized by using novel methodology. This material was very effectively capitalized as a new carbon‐based acid–base cooperative catalyst for sequential acetal hydrolysis and Knoevenagel condensation reactions. The protocol was also explored for the nitroaldol condensation reaction.
Three‐Dimensional Porous Carbon–Silicon Frameworks as High‐Performance Anodes for Lithium‐Ion Batteries
Authors: Wang Ming‐Shan , Song Yu , Song Wei‐Li , Fan Li‐Zhen
Published: September 2014

As a promising anode material for lithium‐ion batteries, Si is still facing great challenges owing to the rapid capacity fade, which is mainly caused by the large volume changes during cycling. We have rationally designed novel 3D porous carbon–silicon frameworks by self‐assembly of the phenol formaldehyde resin and triblock copolymer. The triblock copolymer acts as both structure‐directing agent and template for the formation of a uniform carbon shell and the generation of bimodal porous structures. The as‐fabricated porous carbon–silicon (PC–Si) hybrid exhibits an initial capacity of 1868 mA h g−1 with a columbic efficiency of 41 %. The columbic efficiency rapidly increases to 99 % and the capacity remains at ≈1000 mAh g−1 after 100 cycles suggesting a much more stable cycling and enhanced capacitance compared to Si with direct carbon coating. Such an excellent electrochemical performance is attributed to the formation of continuous mesoporous structures in the exclusive 3D conductive frameworks.
First Principles (DFT) Characterization of RhI/dppp‐Catalyzed CH Activation by Tandem 1,2‐Addition/1,4‐Rh Shift Reactions of Norbornene to Phenylboronic Acid
Authors: Kantchev Eric Assen B. , Pangestu Surya R. , Zhou Feng , Sullivan Michael B. , Su Hai‐Bin
Published: September 2014

The CH activation in the tandem, “merry‐go‐round”, [(dppp)Rh]‐catalyzed (dppp=1,3‐bis(diphenylphosphino)propane), four‐fold addition of norborene to PhB(OH)2 has been postulated to occur by a C(alkyl)H oxidative addition to square‐pyramidal RhIIIH species, which in turn undergoes a C(aryl)H reductive elimination. Our DFT calculations confirm the RhI/RhIII mechanism. At the IEFPCM(toluene, 373.15 K)/PBE0/DGDZVP level of theory, the oxidative addition barrier was calculated to be 12.9 kcal mol−1, and that of reductive elimination was 5.0 kcal mol−1. The observed selectivity of the reaction correlates well with the relative energy barriers of the cycle steps. The higher barrier (20.9 kcal mol−1) for norbornyl–Rh protonation ensures that the reaction is steered towards the 1,4‐shift (total barrier of 16.3 kcal mol−1), acting as an equilibration shuttle. The carborhodation (13.2 kcal mol−1) proceeds through a lower barrier than the protonation (16.7 kcal mol−1) of the rearranged aryl–Rh species in the absence of o‐ or m‐substituents, ensuring multiple carborhodations take place. However, for 2,5‐dimethylphenyl, which was used as a model substrate, the barrier for carborhodation is increased to 19.4 kcal mol−1, explaining the observed termination of the reaction at 1,2,3,4‐tetra(exo‐norborn‐2‐yl)benzene. Finally, calculations with (Z)‐2‐butene gave a carborhodation barrier of 20.2 kcal mol−1, suggesting that carborhodation of non‐strained, open‐chain substrates would be disfavored relative to protonation.
Naphthobipyrrole‐Derived Sapphyrins: Rational Synthesis, Characterization, Nonlinear Optical Properties, and Excited‐State Dynamics
Authors: Sarma Tridib , Anusha Puliparambil Thilakan , Pabbathi Ashok , Venugopal Rao Soma , Panda Pradeepta K.
Published: September 2014

Two new free‐base β‐octa and hexaalkyl naphthobipyrrole‐derived sapphyrins are reported along with various salts thereof. One of them has substituents at all of its β positions, whereas the pyrrole unit opposite to the bipyrrolic moiety is unsubstituted in the other. The effect of bipyrrole fusion on the structure of sapphyrins was explored. Interestingly, an unprecedented sandwiched supramolecular aqua‐bridged free‐base sapphyrin dimer was also characterized in the solid state. Further, the effect of anions on the third‐order nonlinear optical properties of these sapphyrins were explored in the salt form, along with their detailed excited‐state dynamics by both degenerate and nondegenerate pump–probe studies.
High Performance Photoinitiating Systems for Holography Recording: Need for a Full Control of Primary Processes
Authors: Ibrahim Ahmad , Allonas Xavier , Ley Christian , Kawamura Koichi , Berneth Horst , Bruder Friedrich‐Karl , Fäcke Thomas , Hagen Rainer , Hönel Dennis , Rölle Thomas , Walze Guenther , Weiser Marc Stephan
Published: September 2014

Optimization of holography recording in photopolymers was studied from the point of view of a quite general process, that is, the photogeneration of radicals. On the basis of a dye/coinitiator photoinitiating system, the effect of primary events and their relative efficiency was investigated with respect to the final overall properties, such as the diffraction efficiency. Quenching of the dye excited states by the borate salts coinitiators exhibits important differences depending on the dye used (Rose Bengal or Safranine O). Keeping in mind that both singlet and triplet states of the dyes can react, and taking into account the viscosity of the matrix, a method to evaluate the overall quantum yield of radicals released is proposed. It is found that this quantum yield well correlates with the maximum rate of photopolymerization. More interestingly, the dose required to obtain a given diffraction efficiency was found to be also governed by the radical quantum yield, showing that the final property is directly governed by primary events. This shed some light on the efficiency of photochemical pathway to generate radicals for use in organic or polymer areas.
Inherently Chiral Macrocyclic Oligothiophenes: Easily Accessible Electrosensitive Cavities with Outstanding Enantioselection Performances
Authors: Sannicolò Francesco , Mussini Patrizia R. , Benincori Tiziana , Cirilli Roberto , Abbate Sergio , Arnaboldi Serena , Casolo Simone , Castiglioni Ettore , Longhi Giovanna , Martinazzo Rocco , Panigati Monica , Pappini Marco , Quartapelle Procopio Elsa , Rizzo Simona
Published: September 2014

Linear conjugated oligothiophenes of variable length and different substitution pattern are ubiquitous in technologically advanced optoelectronic devices, though limitations in application derive from insolubility, scarce processability and chain‐end effects. This study describes an easy access to chiral cyclic oligothiophenes constituted by 12 and 18 fully conjugated thiophene units. Chemical oxidation of an “inherently chiral” sexithiophene monomer, synthesized in two steps from commercially available materials, induces the formation of an elliptical dimer and a triangular trimer endowed with electrosensitive cavities of different tunable sizes. Combination of chirality with electroactivity makes these molecules unique in the current oligothiophenes literature. These macrocycles, which are stable and soluble in most organic solvents, show outstanding chiroptical properties, high circularly polarized luminescence effects and an exceptional enantiorecognition ability.
Coupled‐Cluster Interaction Energies for 200‐Atom Host–Guest Systems
Authors: Andrejić Milica , Ryde Ulf , Mata Ricardo A. , Söderhjelm Pär
Published: September 2014

We have developed a method to calculate interaction energies of large systems (such as host–guest or even protein–ligand systems) at the local coupled‐cluster with singles, doubles, and perturbative triples level, and with extrapolation to the limit of a complete basis set. The method is based on the polarizable multipole interactions with supermolecular pairs molecular fractionation approach, which combines a pairwise quantum‐mechanical evaluation of the short‐range interactions with a polarizable multipole treatment of many‐body effects. The method is tested for nine guest molecules binding to an octa‐acid host (in total 198–207 atoms), as part of the SAMPL4 blind challenge. From the test calculations, the accuracy of the approach is found to be 10 kJ mol−1 or better. Comparison with dispersion‐corrected density functional theory reveals that the latter underestimates the dispersion contribution for this type of system, which leads to a difference in the ranking of the ligands.
Red Blood Cells Polarize Green Laser Light Revealing Hemoglobin′s Enhanced Non‐Fundamental Raman Modes
Authors: Marzec Katarzyna M. , Perez‐Guaita David , de Veij Marleen , McNaughton Don , Baranska Malgorzata , Dixon Matthew W. A. , Tilley Leann , Wood Bayden R.
Published: September 2014

In general, the first overtone modes produce weak bands that appear at approximately twice the wavenumber value of the fundamental transitions in vibrational spectra. Here, we report the existence of a series of enhanced non‐fundamental bands in resonance Raman (RR) spectra recorded for hemoglobin (Hb) inside the highly concentrated heme environment of the red blood cell (RBC) by exciting with a 514.5 nm laser line. Such bands are most intense when detecting parallel‐polarized light. The enhancement is explained through excitonic theory invoking a type C scattering mechanism and bands have been assigned to overtone and combination bands based on symmetry arguments and polarization measurements. By using malaria diagnosis as an example, we demonstrate that combining the non‐fundamental and fundamental regions of the RR spectrum improves the sensitivity and diagnostic capability of the technique. The discovery will have considerable implications for the ongoing development of Raman spectroscopy for blood disease diagnoses and monitoring heme perturbation in response to environmental stimuli.
Cyclizations of Aryl Enynes Containing Propargyl Alcohol and Diallylamine Groups to Yield Indolecarbaldehydes Induced by Ruthenium Complexes
Authors: Feng Yi‐Jhen , Tsai Fu‐Yuan , Huang Shou‐Ling , Liu Yi‐Hong , Lin Ying‐Chih
Published: September 2014

The reactions of RuCl(PPh3)2Cp ([Ru]Cl, Cp = cyclopentadienyl) with aryl enynes 1a–1c containing propargyl alcohol and diallylamine groups on the aryl ring give the carbene complexes 2a–2c, each of which contains an indole group. With an additional methylene group, the aryl enyne 1d reacts with [Ru]Cl to afford the dihydroisoquinoline complex 3d. For 1a–1d, the C–N bond‐forming process occurs when the triple bond is π‐coordinated to the metal center. The reaction of [Ru]Cl with the aryl enyne 1e containing an isoxazole group affords the carbene complex 2e by a C–C bond formation between the isoxazole group and C‐β of the triple bond, accompanied by the opening of the isoxazole ring. The reactions of 2a–2c and 2e with O2/NEt3 are assisted by visible light to afford the corresponding aldehydes 4a–4c and 5e. From DFT calculations, visible light results in the partial population of the lowest unoccupied molecular orbital (LUMO), which has Ru=C antibonding character; therefore, the bond is weakened, and the oxygenation/demetallation reactions are slightly promoted.
Synthesis of Furans through Silver‐Catalyzed Propargyl–Claisen Rearrangement Followed by Cyclocondensation
Authors: Palisse Adeline , Kirsch Stefan F.
Published: September 2014

The generation of highly substituted furans from propargyl vinyl ethers bearing a free hydroxy group was investigated. In the presence of catalytic amounts of AgBF4, a formal [3,3] sigmatropic rearrangement takes place in the first stage of the sequence. The resulting allenyl carbonyl intermediates then undergo cyclocondensation, which upon double‐bond isomerization leads directly to the five‐membered heterocyclic products. This domino reaction allows the synthesis of various tri‐ and tetrasubstituted furan products; an example leading to pyrroles in an analogous way is also described.
Relationship between ambient ultraviolet radiation and non‐Hodgkin lymphoma subtypes: A U.S. population‐based study of racial and ethnic groups
Authors: Cahoon Elizabeth K. , Pfeiffer Ruth M. , Wheeler David C. , Arhancet Juan , Lin Shih‐Wen , Alexander Bruce H. , Linet Martha S. , Freedman D. Michal
Published: September 2014

Associations between ultraviolet radiation (UVR) exposure and non‐Hodgkin lymphoma (NHL) have been inconsistent, but few studies have examined these associations for specific subtypes or across race/ethnicities. We evaluated the relationship between ambient UVR exposure and subtype‐specific NHL incidence for whites, Hispanics and blacks in the United States for years 2001–2010 (n = 187,778 cases). Incidence rate ratios (IRRs) and 95% confidence intervals (CIs) were calculated for UVR quintiles using Poisson regression. Incidence was lower for the highest UVR quintile for chronic/small lymphocytic/leukemia (CLL/SLL) (IRR = 0.87, 95% CI: 0.77–0.97), mantle cell (IRR = 0.82, 95% CI: 0.69–0.97), lymphoplasmacytic (IRR = 0.58, 95% CI: 0.42–0.80), mucosa‐associated lymphoid tissue (MZLMALT) (IRR = 0.74, 95% CI: 0.60–0.90), follicular (FL) (IRR = 0.76, 95% CI: 0.68–0.86), diffuse large B‐cell (IRR = 0.84, 95% CI: 0.76–0.94;), peripheral T‐cell other (PTCL) (IRR = 0.76, 95% CI: 0.61–0.95) and PTCL not otherwise specified (PNOS) (IRR = 0.77, 95% CI: 0.61–0.98). Trends were significant for MZLMALT, FL, DLBCL, BNOS and PTCL, with FL and DLBCL still significant after Bonferroni correction. We found interaction by race/ethnicity for CLL/SLL, FL, Burkitt, PNOS and MF/SS, with CLL/SLL and FL still significant after Bonferroni correction. Some B‐cell lymphomas (CLL/SLL, FL and Burkitt) suggested significant inverse relationships in whites and Hispanics, but not in blacks. Some T‐cell lymphomas suggested the most reduced risk for the highest quintile of UVR among blacks (PNOS and MF/SS), though trends were not significant. These findings strengthen the case for an inverse association of UVR exposure, support modest heterogeneity between NHL subtypes and suggest some differences by race/ethnicity.
Fundamentals and Modeling of Electrokinetic Transport in Nanochannels
Authors: Yeh Hung‐Chun , Wang Moran , Chang Chih‐Chang , Yang Ruey‐Jen
Published: September 2014

When the channel size approaches the thickness of the charged layer (typically, ∼10–100 nm), the resulting molecular and non‐equilibrium effects are markedly different from those observed in larger channels and have a significant effect on the transport behavior of solutes and solvents. As a result, the problem of modeling fluidic behavior at the nanoscale has attracted increasing interest in recent years. This review introduces the fundamental theories and principles associated with electrokinetic transport and molecular dynamics modeling, and discusses various applications of nanofluidic devices in the physics, mechanics, and chemistry fields.
Directed Evolution of Artificial Metalloenzymes
Authors: Ilie Adriana , Reetz Manfred T.
Published: September 2014

Transition metal catalysis in asymmetric transformations plays a pivotal role in modern synthetic organic chemistry, with these catalysts being tuned by systematic variation of the chiral ligand. More than three decades ago it was recognized that an alternative approach is possible, namely the anchoring of an achiral ligand/metal entity in an appropriate protein host, with formation of an artificial metalloenzyme (hybrid catalyst). However, this procedure delivers a single transition metal catalyst, with high enantioselectivity being a matter of chance. In view of this restriction, we proposed in 2001/2002 the concept of directed evolution of such hybrid catalysts. The most intensively studied system involves biotinylated phosphine/metal entities which are non‐covalently anchored to streptavidin. The present review summarizes progress in this intriguing area of research. It includes the assessment of the requirements of a given Darwinian system to be successful, and offers hints on how to achieve success in future studies.
DEVELOPING ABILITIES AND KNOWLEDGE: STYLE IN THE INTERPLAY OF STRUCTURE AND PROCESS
Authors: Messick Samuel
Published: September 2014

As commentary for a special issue on Education and Human Ability of the British journal Educational Analysis, two recurrent themes in the volume are underscored as well as three critical educational issues that were addressed only peripherally there. The two recurrent themes deal with the roles of knowledge and of context in school learning. The three peripheral issues given central focus in the commentary are (1) the role of schooling in the development of cognitive abilities and of developed abilities in the processes of school learning; (2) the role of cognitive styles as characteristic modes of organization and regulation in information processing which afford unifying self‐consistency in learning; and, (3) the problem of the match between features of the instruction and functional characteristics of the learner. The commentary thus centers on some of the salient roles in education and learning of knowledge, abilities, context, and style – especially as they merge in the problem of the match.
EFFECTS ON SCORE DISTRIBUTIONS OF DELETING AN UNKEYABLE ITEM FROM A TEST
Authors: Dorans Neil J.
Published: September 2014

The purpose of this report is to present a formal analysis of the effects of item deletion on equating/scaling functions and reported score distributions. The phrase “item deletion” shall be used to refer to the process of changing the original key of a flawed item to either all options correct, including omits, or to no options correct, i.e., not scoring the flawed item. There are two aspects to the present analysis. The first aspect is analytical, focusing on the development of a formal model for the item deletion effect by decomposing it into its constituent elements. The second component of the analysis is empirical, involving the use of actual data to illustrate and supplement the analytical results. The analytical decomposition demonstrates how the effects of item properties, test properties, individual examinee responses and rounding rules combine to produce the item deletion effect on the equating/scaling function and candidate scores. In addition to demonstrating how the deleted item's psychometric properties can affect the equating function, the analytical component of the report examines the effects of not scoring vs. scoring all options correct and the effects of re‐equating vs. not re‐equating, as well as the interaction between the decision to re‐equate or to not re‐equate and the scoring option chosen for the flawed item. The empirical portion of the report uses data from the May 1982 administration of the SAT, which contained the circles item, to illustrate the effects of item deletion on reported score distributions and equating functions. The empirical data verify what the analytical decomposition predicts.
A REVIEW OF RESEARCH ON THE PREDICTION OF ACADEMIC PERFORMANCE AFTER THE FRESHMAN YEAR
Authors: Wilson Kenneth M.
Published: September 2014

The criterion most frequently used in studies designed to assess the predictive validity of measures used in college admission has been the freshman‐year GPA. It is not self‐evident that the first‐year GPA provides either a sufficient or a representative sample of a student's academic performance. Questions have been raised regarding the validity of admissions measures for predicting longer‐term performance in college. This is the report of a systematic review of research bearing on (a) the validity of admissions measures for predicting GPA that reflects performance beyond the freshman year—i.e., longer‐term cumulative or independently computed post‐freshman‐year GPA, such as senior‐year GPA; (b) the comparative relevance and utility of freshman‐year, cumulative, and independently computed post‐freshman‐year GPA as criteria for the validation of admissions measures. Among other things, the research reviewed lends support to the traditional practice of employing the freshman‐year GPA in admissions‐related predictive validity studies.
SURVEY OF ACADEMIC WRITING TASKS REQUIRED OF GRADUATE AND UNDERGRADUATE FOREIGN STUDENTS
Authors: Bridgeman Brent , Carlson Sybil
Published: September 2014

A survey of the academic writing skills needed by beginning undergraduate and graduate students was conducted. Faculty, in 190 academic departments at thirty‐four U.S. and Canadian universities with high foreign student enrollments completed the questionnaire. At the graduate level, six academic disciplines with relatively high numbers of nonnative students were surveyed: business management (MBA), civil engineering, electrical engineering, psychology, chemistry, and computer science. Undergraduate English departments were chosen to document the skills needed by undergraduate students.

The major findings are summarized below.

Although writing skill was rated as important to success in graduate training, it was consistently rated as even more important to success after graduation.

Even disciplines with relatively light writing requirements (e.g., electrical engineering) reported that some writing is required of first‐year students.

The writing skills perceived as most important varied across departments.

Faculty members reported that, in their evaluations of student writing, they rely more on discourse‐level characteristics than on word‐ or sentence‐level characteristics.

Discourse‐level writing skills of natives and nonnatives were perceived as fairly similar, but significant differences between natives and nonnatives were reported for sentence‐ and word‐level skills and for overall writing.

Among the ten writing sample topic types provided, preferred topic types differed across departments.

Although some important common elements among the different departments were reported, the survey data distinctly indicate that different disciplines do not uniformly agree on the writing task demands and on a single preferred mode of discourse for evaluating entering undergraduate and graduate students.
CONFIDENCE ENVELOPES FOR ITEM RESPONSE THEORY
Authors: Thissen David , Wainer Howard
Published: September 2014

A statistical method is described and illustrated which provides confidence envelopes around item response functions. Examples of 95% confidence envelopes for the one‐, two‐, and three‐parameter logistic response models are given.

In addition, we describe, N‐line plots, which show the genesis of the envelope as well as the density of lines in the confidence region. These too are illustrated for the one‐, two‐, and three‐parameter logistic models.
STYLES, READING STRATEGIES AND TEST PERFORMANCE: A FOLLOW‐UP STUDY OF BEGINNING READERS
Authors: Chittenden Edward A.
Published: September 2014

Follow‐up data consisting of teacher ratings and reading achievement scores (CAT) were collected for twenty children whose early reading progress had been extensively documented in previous observational research. The children in the Follow‐up sample represented two contrasting stylistic groups with distinctive strategies for reading. The data indicated no difference between the groups in general reading ability by the end of the primary grades. There was evidence, however, of stylistic influences on children's responses to measures (subtests) of reading comprehension. Children who broadly relied upon anticipation of meanings, as their entry into text, exhibited reading strategies that were not well suited to constraints of comprehension items, whereas the children whose styles of learning were more linear and more narrowly focused exhibited strategies that were better matched to the task.
ESTIMATING THE IMPUTED SOCIAL COST OF ERRORS OF MEASUREMENT*
Authors: Lord Frederic M.
Published: September 2014

If a loss function is available specifying the social cost of an error of measurement in the score on a unidimensional test, an asymptotic method, based on item response theory, is developed for optimal test design for a specified target population of examinees. Since in the real world such loss functions are not available, it is more useful to reverse this process; thus a method is developed for finding the loss function for which a given test is an optimally designed test for the target population. An illustrative application is presented for one operational test.
THE ROLE OF GRE GENERAL AND SUBJECT TEST SCORES IN GRADUATE PROGRAM ADMISSION
Authors: Oltman Philip K. , Hartnett Rodney T.
Published: September 2014

To learn more about graduate program selectivity, admission test requirements, and the role the Graduate Record Examinations play in the admission process, a two‐phase study was carried out. First, the GRE® General Test and/or Subject Test requirements of a broad range of graduate programs were summarized by examining data in two issues of the Graduate Programs and Admissions Manual. Analyses of these data indicated how many and what kinds of graduate programs do and do not require or recommend GRE test scores. Second, a mail survey of graduate programs was carried out in order to determine their perceptions of the role test scores play in the admission process and to obtain specific information about how they use test score information. The same questionnaire (with appropriate branching instructions) was used to learn why certain programs do not require or recommend GRE scores. The following conclusions were reached:

While variations exist across disciplines, approximately 64 percent of all graduate programs require or recommend submission of GRE scores.

GRE test score requirements have not changed appreciably over the last decade.

There is little relationship between program selectivity and use of GRE scores.

The primary use of GRE scores appears to be to compensate for otherwise weak applicant credentials.

The primary reason given for not using GRE scores is that the departments feel that other data provide an adequate basis for admission decisions.

Graduate departments assign the most importance to undergraduate grades in making admission decisions, followed by letters of recommendation and by GRE scores, with other criteria rated progressively less important.
ANALYSIS OF SCORE CHANGE PATTERNS OF EXAMINEES REPEATING THE GRADUATE RECORD EXAMINATIONS GENERAL TEST1
Authors: Kingston Neal , Turner Nancy
Published: September 2014

The stability of scores over time of the GRE® General Test verbal, quantitative, and analytical measures were studied using data from the self‐selected group of repeaters. Overall, in these analyses the new‐format GRE verbal measure demonstrated the greatest stability over time and the new‐format analytical measure the least.
ETHNIC, SOCIOECONOMIC, AND HOME LANGUAGE INFLUENCES UPON EARLY PERFORMANCE ON MEASURES OF ABILITIES
Authors: Laosa Luis M.
Published: September 2014

The study examined both the levels and the profiles of performance on measures of various abilities by children from Chicano and non‐Hispanic White families of diverse socioeconomic levels, home language backgrounds, and family sizes. Measures were obtained when the children (N = 171) were 2 years and 6 months of age. Five ability areas were studied: verbal, reasoning, quantitative, memory, and motor–measured by the McCarthy Scales of Children's Abilities. Results revealed ethnic group differences in both (a) the absolute levels of performance in some ability areas and (b) the shapes of the profiles formed by the configuration of performance across the various ability areas. These ethnic group differences in performance were explained (statistically) on the basis of a combination of effects associated with ethnic group differences in socioeconomic status and home language.
RESPONSE TO CHANGING ASSESSMENT NEEDS: REDESIGN OF THE NATIONAL ASSESSMENT OF EDUCATIONAL PROGRESS
Authors: Messick Samuel
Published: September 2014

To improve the interpretability, comparability, timeliness, and policy relevance of the results within fixed budgets, the new design for NAEP moves to a biennial schedule assessing four subject‐matter areas in each wave. Reading is assessed in every wave to provide timely reporting of trends in a basic area and to calibrate alternate cohorts; writing is assessed every other wave (4 years), as are math and science in alternate waves. In addition to the traditional assessment of 9‐, 13‐, and 17‐year olds, sampling is expanded to permit reporting of the associated modal grades (with redefined age definitions, the grades are 3, 7, and 11). There are thus four years intervening between subject assessments, age levels, and grade levels, thereby introducing a systematic cohort matching procedure. Balanced‐incomplete spiralling of exercises, as well as of background and program variables, permits the estimation of intercorrelations among all variables. This facilitates dimensional analyses within and across subject areas; item‐response scaling to improve comparability of scale meaning across ages, population groups, and time periods; and, the examination and structural analysis of various policy relevant correlates of educational performance.
A COMPUTER PROGRAM FOR SIMULATION EVALUATION OF IRT ABILITY ESTIMATORS
Authors: Thissen David , Wainer Howard , Rubin David
Published: September 2014

This report documents the computer program which implements the design of our evaluation by simulation of IRT ability estimators (Wainer and Thissen, 1984). The program is reproduced in Appendix A and a sample of its main output file is Appendix B. It is printed here to facilitate the use of any or all of its routines in future investigations.
THE RELATIONSHIP OF GRE GENERAL TEST ITEM‐TYPE PART SCORES TO UNDERGRADUATE GRADES
Authors: Wilson Kenneth M.
Published: September 2014

This study was undertaken (a) to assess the relative contribution of a vocabulary score made up of GRE General Test antonyms and analogies and a reading comprehension score made up of GRE sentence completions and reading comprehension sets to prediction of an academic criterion (self‐reported undergraduate grade point average) and (b) to assess patterns of criterion‐related validity for item‐type part scores on the GRE quantitative and analytical measures as well.

The study was based on data from GRE files for 9,375 examinees in 12 fields of study representing 437 undergraduate departments from 149 colleges and universities. All data were standardized within each undergraduate department and then pooled for analysis by field.

There were differences by major field in average performance on the various item‐type part scores within each test. The reading comprehension subtest was found to carry most of the predictive load in the GRE verbal measure (consistent with findings for the reading comprehension subscore on the SAT verbal measure). Item‐type part scores on the other measures also exhibited differential patterns of relationships with the self‐reported undergraduate grade point average.

The findings suggest that the different item types within the respective broad ability measures may be tapping somewhat unique skills and abilities and that further exploration of their potential contribution is in order.
FACTOR STRUCTURE OF THE GRE GENERAL TEST FOR OLDER EXAMINEES: IMPLICATIONS FOR CONSTRUCT VALIDITY
Authors: Stricker Lawrence J. , Rock Donald A.
Published: September 2014

The aim of this study was to appraise the extent to which the GRE General Test has the same construct validity for older test takers as it has for other examinees by comparing the interrelationships among the test items for subgroups of examinees defined by age. The items in the test were factor analyzed for three samples of examinees, 20‐29 years old, 30‐39 years old, and 40‐49 years old. The same verbal, quantitative, and analytical ability factors were found in each sample, but the intercorrelations of the factors increased slightly, though consistently, with the age of the sample. These results suggest that the convergent validity of the test is similar across these age groups, but the discriminant validity is somewhat different for the older examinees. It was also found, in each sample, that the items in the analytical measure had a substantial amount of specific variance and that the analytical ability factor was highly correlated with the other factors, implying that these items have relatively little in common with each other and overlap excessively with verbal and quantitative ability.
TEST SPEEDEDNESS UNDER NUMBER‐RIGHT SCORING: AN ANALYSIS OF THE TEST OF ENGLISH AS A FOREIGN LANGUAGE
Authors: Bejar Isaac I.
Published: September 2014

This investigation aimed to develop a new methodology for assessing the speededness of right‐scored tests such as the Test of English as a Foreign Language (TOEFL). A new methodology is needed because traditional procedures of assessing speededness assume that the test is scored under formula‐scoring instructions. The approach to the problem used in this study capitalizes on the fact that Item Response Theory is used in equating TOEFL. Two indices were investigated and validated against artificial data and real data in a way that was consistent with the ETS criteria for declaring forms speeded. Both indices were able to identify data that contained the speed component. The applications of these indices to several forms suggest that speed does not play a significant role in the TOEFL as a whole. However, Section 2 appeared to be affected by speed in administrations where pretest items are included. This may have been due to the slightly shorter time per item allowed when pretest items are included. It was recommended that one of the indices studied be used on an operational basis for a trial period and that the time limit for Section 2 be increased when pretest items are present or that the number of items be reduced to achieve the same effect.
FIELD TRIAL OF A USER‐ORIENTED ADAPTATION OF THE INVENTORY OF DOCUMENTED ACCOMPLISHMENTS AS A TOOL IN GRADUATE ADMISSIONS
Authors: Baird Leonard L.
Published: September 2014

A user‐oriented application survey was constructed, building on the work of the project to develop an inventory of documented accomplishments. The survey was sent to a small group of interested departments. The experiences and reactions of these departments to the structured admissions survey were reviewed, and the survey revised accordingly. Eighteen departments in three universities agreed to use this revised instrument as part of their regular admissions procedures. They were subsequently polled for their reactions to the form's utility, content, interpretability, advantages over current procedures, and comparability with the personal statement. In general, it appeared unlikely that a single form could be developed that would have appeal and applicability across fields.
XTREE: A MULTIVARIATE GRAPHICAL ICON WITH SPECIAL APPLICABILITY IN MONTE CARLO STUDIES1
Authors: Thissen David , Wainer Howard
Published: September 2014

Computer simulations are often used to compare statistical estimators. A common structure (e.g., Andrews, et. al., 1972) of these Monte Carlo studies is to compare a number of estimators for a number of distributions under a number of side conditions (i.e., various sample sizes). The investigator is faced with a substantial problem in trying to interpret voluminous output. The problem is exacerbated if there are multiple dependent variables (e.g., variance and bias). In this paper we propose a graphical icon, the XTREE, which aids perception and interpretation of such results. The method is illustrated with data from two recently published studies. A computer program that draws this display is provided.
LANGUAGE FACTORS AND HISPANIC FRESHMEN'S STUDENT PROFILE
Authors: Duran Richard P. , Enright Mary K. , Rock Donald A.
Published: September 2014

This study investigated the role of language factors as potential determinants of Hispanics' educational progress. Hispanic as well as non‐Hispanic educators have argued that if we knew more about Hispanics' language background and language skills, we might improve the assessment of their cognitive and academic skills. More specifically, the purpose of this study was to investigate the relationship of language background factors to measures of college aptitude as measured by the Scholastic Aptitude Test (SAT) and other College Board Admissions Testing Program achievement and placement tests. Language background factors that were studied included amount of exposure to both Spanish and English, frequency of use of the two languages, and proficiency in each language.

The students surveyed were freshmen in the fall of 1982 who were attending a sample of four‐year institutions that were participating in the College Board's Summary Reporting Service. The data analyzed included test scores, responses to the Student Descriptive Questionnaire (SDQ), and a special questionnaire supplement that included 36 items dealing with language background and language proficiency questions.

The major questions that were addressed by this study were: (1) How did Hispanic freshmen vary with respect to their perceptions of language use and proficiency? (2) What were the relationships between their self‐perceptions of their language skills and their test scores? (3) Were there specific language survey questions that would add to the utility of the SDQ in predicting SAT scores?

The principal findings of the study indicated that a large number of non‐SDQ language questions were more highly related to SAT and TSWE test performance than was the existing SDQ question 38 (Is English your best language?). Language survey items probing preferences for using Spanish versus English and freshmen's self‐ratings of English language proficiency seemed to be the most outstanding predictors of SAT‐verbal scores as well as TSWE scores. Many of the language survey questions improved the prediction of the SAT scores by 10 percent or more when used in combination with the SDQ question 38. In addition, the importance of language survey questions as predictors of SAT‐verbal scores varied by Spanish language group, with language survey items being most important for Puerto Ricans.
THE PSYCHOMETRIC CHARACTERISTICS OF THE SAT FOR NINE HANDICAPPED GROUPS
Authors: Bennett Randy Elliot , Rock Donald A. , Kaplan Bruce A.
Published: September 2014

This study examined the psychometric characteristics of the Scholastic Aptitude Test (SAT) administered under special conditions for nine handicapped groups. Information about test characteristics is central to judging the accuracy and fairness of scores from SAT special administrations.

Four psychometric characteristics were studied: level of test performance, test reliability, speededness, and extent of unexpected differential item performance. Psychometric comparisons were made between a nonhandicapped sample and each of nine different handicapped classifications. These contrasts were carried out twice; that is, they were replicated across two forms of the same test. The use of two samples taking different forms served to increase confidence in the stability of results and their applicability to other forms of the SAT.

Results of the study showed that visually impaired students and those with physical handicaps achieved mean scores generally comparable to students taking the SAT in national administrations. Learning disabled and hearing impaired students scored lower than their nondisabled peers. Differences between Verbal and Mathematical performance were also comparable to those for the nondisabled reference group in all but the hearing impaired‐regular type test and visually impaired‐braille test samples. Hearing impaired‐regular students scored higher on Mathematical than on Verbal relative to their nondisabled peers, while visually impaired‐braille students showed no consistent superiority for Mathematical over Verbal.

Analysis of test reliability revealed no practical differences in measurement precision across groups. Data on test speededness showed no evidence of disadvantage for disabled students; the amount of extended time allotted through special administrations appears to allow roughly equivalent proportions of handicapped and nondisabled examinees to complete the test.

Because of the large number of groups and test items involved, unexpected differential item performance was examined through a two‐stage procedure. The first stage centered on the performance of item clusters. Individual items composing clusters showing questionable performance were then examined. This two‐stage procedure revealed only a few instances of differential item performance localized to visually impaired students taking the braille test.

It is concluded that, with the exception of performance level, the psychometric characteristics of the SAT are generally comparable for the handicapped and nondisabled groups studied. These results lend support to the contention that scores from special administrations are fair and accurate measures of the developed scholastic abilities of handicapped students. Further studies of these scores–in particular, their factor structure and predictive validity–should provide additional information about their meaning for handicapped students.
THE INTERNAL CONSTRUCT VALIDITY OF THE SAT ACROSS HANDICAPPED AND NONHANDICAPPED POPULATIONS
Authors: Rock Donald A. , Bennett Randy Elliot , Kaplan Bruce A.
Published: September 2014

This study investigated the comparability of SAT Verbal and Mathematical scores for one nonhandicapped and nine handicapped populations. A simple two‐factor model based on Verbal and Mathematical item parcels was posed and tested for invariance across populations with respect to: (1) the number and intercorrelation of factors, (2) the pattern of factor loadings, and (3) the equality of scale units.

The two common‐factor model provided a reasonable fit in all populations, with the mathematical reasoning factor generally showing a better fit to the population data than the verbal reasoning factor. Compared with the nonhandicapped population, these factors tended to be less correlated in most of the handicapped groups. This somewhat greater specificity implies the increased likelihood of achievement growth in one area independent of the other, suggesting that the two scores be interpreted separately rather than as an SAT composite.

With respect to the pattern of factor loadings, some indication of the presence of two verbal method factors was discovered. Antonym items and, to a lesser extent, reading comprehension items formed such factors. While present to a certain extent for all groups, the method variance seemed to be somewhat greater for the learning disabled populations.

Finally, there was evidence that multiple‐choice Mathematical items led to different observed score scale units for the learning disabled students taking a cassette administration. Because of the small sample sizes on which this finding is based, it should be treated with caution. However, if dependable, the finding suggests that Mathematical scores may underestimate the reasoning ability of these students.
RELATIONSHIPS OF TEST ITEM CHARACTERISTICS TO TEST PREPARATION/TEST PRACTICE EFFECTS: A QUANTITATIVE SUMMARY
Authors: Powers Donald E.
Published: September 2014

Ten studies of the effects of test preparation or test practice were located that provided effect estimates for individual test item types. These item‐level effects were related to a number of test item characteristics, including item format, difficulty level, and complexity of test directions. Strong relationships were noted between test preparation/practice effects and (a) the length and complexity of test directions and (b) the item format employed. Suggestions are made for further research on the relationship of test item characteristics to the susceptibility of tests to coaching and practice.
A PSYCHOMETRIC ANALYSIS OF A THREE‐DIMENSIONAL SPATIAL TASK
Authors: Bejar Isaac I.
Published: September 2014

This paper considers the feasibility of incorporating research results from cognitive science into the modeling of performance on psychometric tests and the construction of test items. The paper focuses on the feasibility of modeling performance on a three‐dimensional rotation task within the context of Item Response Theory (IRT). Three‐dimensional items were chosen because there is a rich literature on the mental models that are used in their solution. To test the feasibility of psychometrically modeling performance on this item type an 80‐item, three‐dimensional rotation test was constructed. An inexpensive computer system was also developed to administer the test and record performance, including response‐time data. Data were collected on high school juniors and seniors. As expected, angular disparity was a potent determinant of item difficulty. The applicability of IRT to these data was investigated by dichotomizing response time at several points and applying standard item parameter estimation procedures. It was concluded that an approach to psychometric modeling that explicitly incorporates information on the mental models examiners use in solving an item is not only workable, but also essential for future developments in psychometrics.
LARGE‐SCALE EDUCATIONAL ASSESSMENT AS POLICY RESEARCH: ASPIRATIONS AND LIMITATIONS1
Authors: Messick Samuel
Published: September 2014

Critical features important for transforming large‐scale educational assessment into effective policy research are examined. These include a developmental orientation to time‐ordered data, empirically‐grounded construct interpretations of measures and relationships, speculative inquiry into the role of diverse contributing factors, and appraisal of alternative perspectives on both the questions and the findings.