Showing papers by "University of Memphis published in 1995"

The Abbreviated Profile of Hearing Aid Benefit

Abstract: ObjectiveTo develop and evaluate a shortened version of the Profile of Hearing Aid Benefit, to be called the Abbreviated Profile of Hearing Aid Benefit, or APHAB.DesignThe Profile of Hearing Aid Benefit (PHAB) is a 66-item self-assessment, disability-based inventory that can be used to document the

Differential effects of aging on memory for content and context: a meta-analysis.

Abstract: The authors reviewed the evidence of age differences in episodic memory for content of a message and the context associated with it. Specifically, the authors tested a hypothesis that memory for context is more vulnerable to aging than memory for content. In addition, the authors inquired whether effort at encoding and retrieval and type of stimulus material moderate the magnitude of age differences in both memory domains. The results of the meta-analysis of 46 studies confirmed the main hypothesis: Age differences in context memory are reliably greater than those in memory for content. Tasks that required greater effort during retrieval yielded larger age differences in content but not in context memory. The greatest magnitude of age differences in context memory was observed for those contextual features that were more likely to have been encoded independently from content. Possible mechanisms that may underlie age differences in context memory-attentional deficit, reduced working memory capacity, and failure of inhibitory processing are discussed.

Collaborative dialogue patterns in naturalistic one-to-one tutoring

Abstract: Naturalistic one-to-one tutoring is more effective than traditional classroom teaching methods, but there have been few attempts to examine the features of normal tutoring that might explain its advantage. This project explored dialogue patterns in two samples of naturalistic tutoring with normal unskilled tutors (as opposed to expert tutors): graduate students tutoring undergraduates in research methods and high school students tutoring 7th graders in algebra. We analysed the extent to which those tutoring protocols manifested components that have been emphasized in contemporary pedagogical theories and intelligent tutoring systems: active student learning, sophisticated pedagogical strategies, specific examples and cases, collaborative problem solving and question answering, deep explanatory reasoning, convergance toward shared meanings, feedback, error diagnosis and remediation, and affect. The most prominent components consisted of collaborative problem solving, question answering, and explanation in the context of specific examples. We identify frequent dialogue patterns that characterize these collaborative processes.

Competitiveness through Management of Diversity: Effects on Stock Price Valuation

Abstract: This study's premise is that firms that can lower their costs and enhance their differentiation through the effective management of their human resources have a competitive advantage. Using data fr...

Cointegration, Error Correction, and Price Discovery on Informationally Linked Security Markets

Abstract: Using synchronous transactions data for IBM from the New York, Pacific, and Midwest Stock Exchanges, we estimate an error correction model to investigate whether each of the exchanges is contributing to price discovery. Johansen's test yields two cointegrating vectors, which together verify the expected long-run equilibrium of equal prices across the three exchanges. Two error correction terms specified as the differences from IBM prices on the NYSE indicate that adjustments maintaining the long-run cointegration equilibrium take place on all three exchanges. That is, IBM prices on the NYSE adjust toward IBM prices on the Midwest and Pacific Exchanges, just as Midwest and Pacific prices adjust to the NYSE.

Managerial Perceptions of Employee Commitment to the Organization

Abstract: A model incorporating antecedents and outcomes of measures of manager-rated employee affective and continuance commitment was tested with 231 managers and 339 subordinates. Organizational citizensh...

Guiding Principles for Evaluators

Abstract: Presented here is the version of the American Evaluation Association Guiding Principles for Evaluators that was approved and copyrighted by the AEA board of directors and subsequently adopted by vote of the AEA membership.

Children's Environmental Attitude and Knowledge Scale: Construction and Validation

Abstract: In this article, the construction and validation of an environmental attitude and knowledge scale designed for children are described. The scale fills a need, expressed by several writers in environmental education, for a research instrument that has sound psychometric properties, can be used in a variety of research settings, and will allow comparisons of results across studies.

Artificial Minds

Abstract: From the Publisher: Stan Franklin is the perfect tour guide through the contemporary interdisciplinary matrix of artificial intelligence, cognitive science, cognitive neuroscience, artificial neural networks, artificial life, and robotics that is producing a new paradigm of mind. Along the way, Franklin makes the case for a perspective that rejects a rigid distinction between mind and non-mind in favor of a continuum from less to more mind, and for the role of mind as a control structure with the essential task of choosing the next action. Selected stops include the best of the work in these different fields, with the key concepts and results explained in just enough detail to allow readers to decide for themselves why the work is significant. Major attractions include animal minds, Newell's SOAR, the three Artificial Intelligence debates, Holland's genetic algorithms, Wilson's Animat, Brooks' subsumption architecture, Jackson's pandemonium architecture, Ornstein's multimind, Minsky's society of mind, Maes's behavior networks, Edelman's neural Darwinism, Drescher's schema mechanisms, Kanerva's sparse distributed memory, Hofstadter and Mitchell's Copycat, and Agre and Chapman's deictic representations.

A Longitudinal Analysis of Accelerated Weight Gain in Preschool Children

Abstract: The purpose of the current investigation was to determine the dietary, physical activity, family history, and demographic predictors of relative weight change in a cohort of 146 children over a 3-year period. Results indicated that boys of normal-weight parents or who had only one parent overweight showed decreases in their body mass index (BMI) while those with two parents overweight showed increases. Girls with an overweight father showed BMI increases while others experienced decreases in BMI. Additionally, baseline intake of kilocalories from fat as well as decreases in fat intake were related to decreases in BMI. At higher levels of baseline aerobic activity, subsequent changes in BMI decreased. There was also a trend for changes in leisure activity—increases in children9s leisure activity was associated with decreases in subsequent weight gain. Modifiable variables (ie, dietary intake, physical activity) accounted for more of the variance in changes in child BMI change than nonmodifiable variables (eg, number of parents obese). These results strongly suggest that encouragement of heart healthy dietary intake patterns and participation in physical activity can decrease accelerated weight gain and obesity, even in preschool children.

Selective neuroanatomic abnormalities in Down's syndrome and their cognitive correlates: evidence from MRI morphometry.

Abstract: Article abstract—We examined the pattern of neuroanatomic abnormalities in adults with Down9s syndrome (DS) and the cognitive correlates of these abnormalities. Specifically, we compared this pattern with what would be predicted by the hypotheses attributing DS pathology to either premature aging or Alzheimer9s disease. We measured a number of brain regions on MRIs of 25 subjects: 13 persons with the DS phenotype and 12 age- and sex-matched healthy volunteers. Study participants had no history of cardiovascular disease, diabetes, thyroid dysfunction, or seizure disorder. After statistical adjustment for differences in body size, we found that, in comparison with controls, DS subjects had substantially smaller cerebral and cerebellar hemispheres, ventral pons, mammillary bodies, and hip-pocampal formations. In the cerebellar vermis of DS subjects, we observed smaller lobules VI to VIII without appreciable differences in other regions. In addition, we noted trends for shrinkage of the dorsolateral prefrontal cortex, anterior cingulate gyrus, inferior temporal and parietal cortices, parietal white matter, and pericalcarine cortex in DS subjects compared with normal controls. The parahippocampal gyrus was larger in DS subjects. We found no significant group differences in the volumes of the prefiontal white matter, the orbitofiontal cortex, the pre- and postcentral gyri, or the basal ganglia. We conclude that the pattern of selective cerebral damage in DS does not clearly fit the predictions of the premature aging or Alzheimer9s disease hypotheses. To examine the relationship between brain abnormalities and cognitive deficits observed in DS, we correlated the size of brain regions that were significantly reduced in DS with performance on tests of intelligence and language. The correlational analysis suggested age-related decline in the DS subjects in general intelligence and basic linguistic skills. General intelligence and mastery of linguistic concepts correlated negatively with the volume of the parahippocampal gyrus. There was no relationship between total brain size and the cognitive variables.

PREVENTING SCHOOL FAILURE, DRUG USE, AND DELINQUENCY AMONG LOW-INCOME CHILDREN: Long-Term Intervention in Elementary Schools

Abstract: A six-year, school-based prevention program, which modified classroom teacher practices, offered parent training, and provided child social skills training, was evaluated for its effects on school failure, drug abuse, and delinquency among low-income urban children. Compared to a low-income control group, children in the intervention group showed enhanced school commitment and class participation. The girls in the group also evidenced lower rates of substance use initiation, while the boys exhibited increased social and school work skills.

Who underreports dietary intake in a dietary recall? Evidence from the Second National Health and Nutrition Examination Survey.

Abstract: The present study sought to identify the presence and degree of apparent underreporting of dietary intake in 11,663 participants in the Second National Health and Nutrition Examination Survey (NHANES II). Self-reported dietary intake was compared with estimated basal metabolic rate. Underreporting was based on cutoff limits that identified plausible levels of energy expenditure for adult individuals. Results indicated that up to 31% of adults in this sample may have underreported dietary intake. Those individuals at greatest risk of underreporting were less well educated and heavier. The Sex x Race interaction indicated that for both ethnic categories, women were more likely to underreport than men, but the difference between men and women was greater among Caucasian participants. It is concluded that such factors as reduced energy needs, deliberate falsification, and measurement error inherent in dietary assessment contribute to apparent underreporting, and this occurs in a large percentage of dietary data.

The influence of sex, age, and handedness on corpus callosum morphology: A meta-analysis

Abstract: Initial observations linking variation in the human corpus callosum (CC) to handedness and sex have inspired a number of investigations of individual differences in CC size and morphology. In this quantitative review, we summarize the findings from these studies and assess the magnitude of sex, age, and handedness-related variations in the size of the CC. Meta-analysis of the 43 studies indicated that although absolute CC and splenial area are larger in men than in women, CC area adjusted for brain size was larger in women. Left-handers possess slightly larger CCs than do right-handers, and CC area decreases slightly with age. The implications of these findings for theories relating cerebral laterality to sex, age, and handedness are discussed.

Euclidean spanners: short, thin, and lanky

Abstract: Euclidean spanners are important data structures in geometric algorithm design, because they provide a means of approximating the complete Euclidean graph with only O(n) edges, so that the shortest path length between each pair of points is not more than a constant factor longer than the Euclidean distance between the points. In many applications of spanners, it is important that the spanner possess a number of additional properties: low tot al edge weight, bounded degree, and low diameter. Existing research on spanners has considered one property or the other. We show that it is possible to build spanners in optimal O (n log n) time and O(n) space that achieve optimal or near optimal tradeoffs between all combinations of these *Max-Planck-Institut fiir Informatik, D-66123 Saarbrucken, Germany. Email: {arya, michiel}@mpi-sb. mpg. de. Supported by the ESPRIT Basic Research Actions Program, under contract No. 7141 (project ALCOM 11). t Math Sciences Dept., The University of Memphis, Memphis, TN 38152. Supported in part by NSF Grant CCR9306822. E-mail: dasg@next 1.msci .memst . edu. i Department of Computer Science and Institute for Advanced Computer Studies, University of Maryland, College Park, Maryland. Partially supported by NSF Grant CCR-93107O5. This work was done while visiting the Max-Planck-Institut fiir Informatik, Saarbriicken. E-mail: mount @cs. umd. edu. SQue~Tech, IIIC., 7600A Leesburg Pike, Falls Church, VA 22043. This work was done while visiting the Max-Planck-Institut fiir Informatik, Saarbriicken. E-mail: jsalowet!nvl, army .mil. Permission to copy without fee all or part of thk material is granted provided that the copies are not made or distributed for direct commercial advantage, the ACM copyri ht notice and the title of thq publication and, is date appear, a#notice is given that copyt~isby~n,sslon of the Ass@ationof Computing Machinery. o cop otherwise, or to republish, requires a fee ancf/or speci ic permission. STOC’ 95, Las Vegas, Nevada, USA @ 1995 ACM 0-89791 -718-9/95/0005..$3.50 properties. We achieve these results in large part because of a new structure, called the dumbbell tree which provides a method of decomposing a spanner into a constant number of trees, so that each of the O(n2) spanner paths is mapped entirely to a path in one of these trees.

Two Cues for Verbal Irony: Hyperbole and the Ironic Tone of Voice

Abstract: The study reported here addresses some of the cues that are used in verbal irony. Irony may be accompanied by a slow speaking rate, heavy stress, and nasalization. The importance of this "ironic tone of voice" has been examined in a number of developmental studies, but its importance remains unclear. The ironic tone of voice may be confounded with the presence of hyperbole, or exaggeration. In order to assess its importance, hyperbole is orthogonally manipulated in a number of short scenarios. Veridicality, a known cue for irony, is also manipulated. Both factors exert significant effects on the perception of verbal, irony. Hyperbole by itself suggests ironic intent in some cases, it may be the case that the ironic tone of voice is nothing more than the use of exaggeration.

Computer Modeling of Intracranial Saccular and Lateral Aneurysms for the Study of Their Hemodynamics

Abstract: There is strong evidence indicating hemodynamic stress as an underlying cause for saccular intracranial aneurysm growth, thrombosis, and/or rupture. We examined flow fields encountered in models of cerebral aneurysms having a lateral (originating from the side of an artery, not at a branch point) geometric configuration. Shear stress and pressure gradients acting on aneurysm walls under a variety of flow and geometric conditions were evaluated. For this purpose, a two-dimensional finite-element computer model of lateral aneurysms in a steady-flow state was developed. Three idealized aneurysm shapes were studied, half-spherical, spherical, and pear-shaped. The ostium width of the cerebral aneurysm, relative to the radius of the parent artery and the Reynolds number, were also varied. Maximal shear stresses and maximum pressures (for an ostium width of 2 times the radius of the parent artery) were typically found at the downstream site of the ostium, rather than at the dome of the aneurysm. In general, the highest shear stresses and the lowest pressures (at the distal portion of the ostium) were obtained in the spherical aneurysm, whereas the lowest shear stresses and the highest pressures were found in the half-spherical aneurysm. The location of maximal stresses (shear and pressure) at the distal region of the ostium suggests that growth and/or rupture may well proceed from this point. Such findings are in contrast to the commonly held opinion that aneurysm rupture occurs at the dome. Careful pathological investigation will need to be performed to clarify this finding. The results of this preliminary investigation also indicate that the flow field in lateral aneurysms is highly dependent on a number of factors related to flow and geometric parameters. Geometry seems to be a significant mediator of local magnitudes of stress. Thus, the tendency for growth or thrombosis may be influenced by variations in size or shape.

The efficacy and effectiveness of marital and family therapy: a perspective from meta‐analysis

Abstract: This article reviews the major findings from a multiproject meta-analysis of the effects of marital and family therapy (MFT). Across 163 randomized trials, MFT demonstrates moderate, statistically significant, and often clinically significant effects. No orientation is yet demonstrably superior to any other, nor is MFT superior to individual therapy. Cost effectiveness information is scant in these 163 studies, but supportive. Randomized experiments yield very different answers from nonrandomized experimental studies of the effects of MFT, calling into question whether we should mix the two in reviews. We have also found several new differences in the ways that marital therapy (MT) and family therapy (FT) studies are conducted, making them harder to compare. Finally, important questions still exist about whether any psychotherapy, including MFT, yet has sufficient information about how well research generalizes to everyday clinical practice.

Investigation of Natural Frequencies and Mode Shapes of Buckled Beams

Abstract: The linear modes of vibration of buckled beams are investigated analytically and experimentally. Assuming a static buckled shape corresponding to the nth buckling mode, an exact solution is obtained for the linear modes and associated frequencies of initially buckled beams with fixed-fixed, fixed-hinged, and hinged-hinged boundary conditions. The analytical solution for a first-mode buckled beam is validated experimentally for the fixed-fixed case. The analytically obtained natural frequencies are in excellent agreement with those obtained experimentally. These exact linear modes provide a basis from which to study the nonlinear vibrations of buckled beams.

Novel Word Learning in Children With Hearing Impairment

Abstract: This study examined novel word-learning abilities in young school-age children with mild-to-moderate hearing losses. We questioned whether degree of hearing loss or measures of language and phonolo...

The Influences of Friends' and Parental Smoking on Adolescent Smoking Behavior: The Effects of Time and Prior Smoking1

Abstract: This research examines the relative importance of parental and friends' influences on adolescents' smoking behavior and changes in the effects of social influences during adolescence. Data were collected at 4 times from 7th to 9th grades. Random-effects ordinal regression models were employed to predict the repeated classification of adolescent smoking status using time effects, prior smoking status, friends' smoking, and parental smoking. In general, the effects of friends' smoking are stronger than those of parental smoking, and these differences increase over time. In addition, friends' smoking has greater effects on nonsmokers than smokers. Separate models for males and females disclose some gender differences. In particular, the effects of friends' smoking are stronger for females than for males, and the increasing trend of friends' influences is more noticeable for females than for males. Models for 4 ethnic groups also suggest differential susceptibility to social influences in different cultures.

Sleep compression and sleep education for older insomniacs: self-help versus therapist guidance.

Abstract: A treatment package consisting of a bed-time restriction strategy and education was administered to 50 insomniacs and 50 noninsomniacs 60 years or older. Half of the insomniacs and noninsomniacs received treatment through a self-help video only, whereas the remaining treated participants received therapist guidance to supplement the video. A waiting-list control group of 25 senior insomniacs was also included. Sleep knowledge was equivalent for senior insomniacs and noninsomniacs. The self-help insomniac group exhibited improvement on multiple sleep variables, but the addition of therapist guidance appeared to enhance treatment outcome for sleep latency, wake time after sleep onset, and sleep satisfaction. Control participants also improved across time but were generally outperformed by treated insomniacs.