Showing papers by "University of Michigan published in 1990"

Motivational and self-regulated learning components of classroom academic performance.

Abstract: A correlational study examined relationships between motivational orientation, self-regulated learning, and classroom academic performance for 173 seventh graders from eight science and seven English classes. A self-report measure of student self-efficacy, intrinsic value, test anxiety, self-regulation, and use of learning strategies was administered, and performance data were obtained from work on classroom assignments. Self-efficacy and intrinsic value were positively related to cognitive engagement and performance. Regression analyses revealed that, depending on the outcome measure, self-regulation, self-efficacy, and test anxiety emerged as the best predictors of performance. Intrinsic value did not have a direct influence on performance but was strongly related to self-regulation and cognitive strategy use, regardless of prior achievement level. The implications of individual differences in motivational orientation for cognitive engagement and self-regulation in the classroom are discussed. Self-regulation of cognition and behavior is an important aspect of student learning and academic performance in the classroom context (Corno & Mandinach, 1983; Corno & Rohrkemper, 1985). There are a variety of definitions of selfregulated learning, but three components seem especially important for classroom performance. First, self-regulated learning includes students' metacognitive strategies for planning, monitoring, and modifying their cognition (e.g., Brown, Bransford, Campione, & Ferrara, 1983; Corno, 1986; Zim

The wavelet transform, time-frequency localization and signal analysis

Abstract: Two different procedures for effecting a frequency analysis of a time-dependent signal locally in time are studied. The first procedure is the short-time or windowed Fourier transform; the second is the wavelet transform, in which high-frequency components are studied with sharper time resolution than low-frequency components. The similarities and the differences between these two methods are discussed. For both schemes a detailed study is made of the reconstruction method and its stability as a function of the chosen time-frequency density. Finally, the notion of time-frequency localization is made precise, within this framework, by two localization theorems. >

Cognitive Elements of Empowerment: An “Interpretive” Model of Intrinsic Task Motivation

Abstract: This article presents a cognitive model of empowerment. Here, empowerment is defined as increased intrinsic task motivation, and our subsequent model identifies four cognitions (task assessments) as the basis for worker empowerment: sense of impact, competence, meaningfulness, and choice. Adopting an interpretive perspective, we have used the model also to describe cognitive processes through which workers reach these conclusions. Central to the processes we describe are workers' interpretive styles and global beliefs. Both preliminary evidence for the model and general implications for research are discussed.

Information technology implementation research: a technological diffusion approach

Abstract: Based on the innovation and technological diffusion literatures, promising research questions concerning the implementation of a production and inventory control information system material requirements planning: MRP are identified and empirically examined. These questions focus on the interaction of managerial tasks with the information technology and the resulting effect on the adoption and infusion of that technology. Using a random sample of manufacturing firms across the United States, we find that this interaction does indeed affect the adoption of MRP, though it does not seem to affect MRP infusion. These results support the notion that though rational decision models may be useful in explaining information technology adoption, political and learning models may be more useful when examining infusion.

The Impact of Economic Hardship on Black Families and Children: Psychological Distress, Parenting, and Socioemotional Development

Abstract: Family processes affecting the socioemotional functioning of children living in poor families and families experiencing economic decline are reviewed. Black children are of primary interest in the article because they experience disproportionate shares of the burden of poverty and economic loss and are at substantially higher risk than white children of experiencing attendant socioemotional problems. It is argued that (a) poverty and economic loss diminish the capacity for supportive, consistent, and involved parenting and render parents more vulnerable to the debilitating effects of negative life events, (b) a major mediator of the link between economic hardship and parenting behavior is psychological distress deriving from an excess of negative life events, undesirable chronic conditions, and the absence and disruption of marital bonds, (c) economic hardship adversely affects children's socioemotional functioning in part through its impact on the parent's behavior toward the child, and (d) father-child relations under conditions of economic hardship depend on the quality of relations between the mother and father. The extent to which psychological distress is a source of race differences in parenting behavior is considered. Finally, attention is given to the mechanisms by which parents' social networks reduce emotional strain, lessen the tendency toward punitive, coercive, and inconsistent parenting behavior, and, in turn, foster positive socioemotional development in economically deprived children.

The American College of Rheumatology criteria for the classification and reporting of osteoarthritis of the hip.

Abstract: Clinical criteria for the classification of patients with hip pain associated with osteoarthritis (OA) were developed through a multicenter study. Data from 201 patients who had experienced hip pain for most days of the prior month were analyzed. The comparison group of patients had other causes of hip pain, such as rheumatoid arthritis or spondylarthropathy. Variables from the medical history, physical examination, laboratory tests, and radiographs were used to develop different sets of criteria to serve different investigative purposes. Multivariate methods included the traditional "number of criteria present" format and "classification tree" techniques. Clinical criteria: A classification tree was developed, without radiographs, for clinical and laboratory criteria or for clinical criteria alone. A patient was classified as having hip OA if pain was present in combination with either 1) hip internal rotation greater than or equal to 15 degrees, pain present on internal rotation of the hip, morning stiffness of the hip for less than or equal to 60 minutes, and age greater than 50 years, or 2) hip internal rotation less than 15 degrees and an erythrocyte sedimentation rate (ESR) less than or equal to 45 mm/hour; if no ESR was obtained, hip flexion less than or equal to 115 degrees was substituted (sensitivity 86%; specificity 75%). Clinical plus radiographic criteria: The traditional format combined pain with at least 2 of the following 3 criteria: osteophytes (femoral or acetabular), joint space narrowing (superior, axial, and/or medial), and ESR less than 20 mm/hour (sensitivity 89%; specificity 91%). The radiographic presence of osteophytes best separated OA patients and controls by the classification tree method (sensitivity 89%; specificity 91%). The "number of criteria present" format yielded criteria and levels of sensitivity and specificity similar to those of the classification tree for the combined clinical and radiographic criteria set. For the clinical criteria set, the classification tree provided much greater specificity. The value of the radiographic presence of an osteophyte in separating patients with OA of the hip from those with hip pain of other causes is emphasized.

Loosely Coupled Systems: A Reconceptualization

Abstract: Diverse applications of the concept of loose coupling are embodied in five recurring voices that focus separately on causation, typology, effects, compensations, and outcomes. Each has a tendency to drift away from a dialectical interpretation of loose coupling toward a unidimensional interpretation of loose coupling, thereby weakening the explanatory value of the concept. The authors first use the five voices to review the loose coupling literature and then to suggest more precise and more productive uses of the concept.

The Child's Theory of Mind

Abstract: Do children have a theory of mind? If they do, at what age is it acquired? What is the content of the theory, and how does it differ from that of adults? "The Child's Theory of Mind "integrates the diverse strands of this rapidly expanding field of study. It charts children's knowledge about a fundamental topic - the mind - and characterizes that developing knowledge as a coherent commonsense theory, strongly advancing the understanding of everyday theories as well as the commonsense theory of mind.Wellman presents evidence that children as young as age three do possess a commonsense theory of mind - that they grasp the distinction between mental constructs and physical entities and that they have an understanding of the relationship between individuals' mental states and their overt actions. He delves in detail into questions about the nature of adults' commonsense theories of mind and about the nature of commonsense theories.Wellman then examines the content of the three-year-old's theory of mind, the nature of children's notions of mind before age three, the changes in the theory during subsequent development from ages three to six, and the young child's conception of mind in comparison with those of older children and adults.Henry M. Wellman is a Professor in the Department of Psychology and the Center for Human Growth and Development at the University of Michigan at Ann Arbor.

Alcohol myopia. Its prized and dangerous effects.

Abstract: This article explains how alcohol makes social responses more extreme, enhances important self-evaluations, and relieves anxiety and depression, effects that underlie both the social destructiveness of alcohol and the reinforcing effects that make it an addictive substance. The theories are based on alcohol's impairment of perception and thought--the myopia it causes--rather than on the ability of alcohol's pharmacology to directly cause specific reactions or on expectations associated with alcohol's use. Three conclusions are offered (a) Alcohol makes social behaviors more extreme by blocking a form of response conflict. (b) The same process can inflate self-evaluations. (c) Alcohol myopia, in combination with distracting activity, can reliably reduce anxiety and depression in all drinkers by making it difficult to allocate attention to the thoughts that provoke these states. These theories are discussed in terms of their significance for the prevention and treatment of alcohol abuse.

Dimensional overlap: cognitive basis for stimulus-response compatibility--a model and taxonomy.

Abstract: The classic problem of stimulus-response (S-R) compatibility (SRC) is addressed. A cognitive model is proposed that views the stimulus and response sets in S-R ensembles as categories with dimensions that may or may not overlap. If they do overlap, the task may be compatible or incompatible, depending on the assigned S-R mapping. If they do not overlap, the task is noncompatible regardless of the assigned mapping. The overlapping dimensions may be relevant or not. The model provides a systematic account of SRC effects, a taxonomy of simple performance tasks that were hitherto thought to be unrelated, and suggestive parallels between these tasks and the experimental paradigms that have traditionally been used to study attentional, controlled, and automatic processes. In this article, we address the classic problem of stimulusresponse (S-R) compatibility (SRC). A model is proposed that attempts to provide a systematic account of performance in highly compatible, incompatible, and noncompatible tasks. At the core of our model is the idea that when a particular S-R ensemble produces either high or low compatibility effects, it is because the stimulus and response sets in the ensemble have properties in common, and elements in the stimulus set automatically activate corresponding elements in the response set. Noncompatible tasks are those in which the stimulus and response sets have nothing in common. If the activated response is the required one, it will be executed rapidly and correctly; if it is not, then it will be relatively slow and error prone. Whether a particular S-R ensemble will produce compatibility effects is often quite easy to determine because of the relationship between the stimulus and response sets. In the part of the model that treats the representational aspects of the problem, we postulate that this relationship is based on the commonality, simi

Correlations in Price Changes and Volatility across International Stock Markets

Abstract: The short-run interdependence of prices and price volatility across three major international stock markets is studied Daily opening and closing prices of major stock indexes for the Tokyo, London, and New York stock markets are examined The analysis utilizes the autoregressive conditionally heteroskedastic (ARCH) family of statistical models to explore these pricing relationships Evidence of price volatility spillovers from New York to Tokyo, London to Tokyo, and New York to London is observed, but no price volatility spillover effects in other directions are found for the pre-October 1987 period Article published by Oxford University Press on behalf of the Society for Financial Studies in its journal, The Review of Financial Studies

Type 1 neurofibromatosis gene: identification of a large transcript disrupted in three NF1 patients

Abstract: Von Recklinghausen neurofibromatosis (NF1) is a common autosomal dominant disorder characterized by abnormalities in multiple tissues derived from the neural crest. No reliable cellular phenotypic marker has been identified, which has hampered direct efforts to identify the gene. The chromosome location of the NF1 gene has been previously mapped genetically to 17q11.2, and data from two NF1 patients with balanced translocations in this region have further narrowed the candidate interval. The use of chromosome jumping and yeast artificial chromosome technology has now led to the identification of a large (approximately 13 kilobases) ubiquitously expressed transcript (denoted NF1LT) from this region that is definitely interrupted by one and most likely by both translocations. Previously identified candidate genes, which failed to show abnormalities in NF1 patients, are apparently located within introns of NF1LT, on the antisense strand. A new mutation patient with NF1 has been identified with a de novo 0.5-kilobase insertion in the NF1LT gene. These observations, together with the high spontaneous mutation rate of NF1 (which is consistent with a large locus), suggest that NF1LT represents the elusive NF1 gene.

On a Decision Method in Restricted Second Order Arithmetic

Abstract: Let SC be the interpreted formalism which makes use of individual variables t, x, y, z,... ranging over natural numbers, monadic predicate variables q( ), r( ), s( ), i( ),... ranging over arbitrary sets of natural numbers, the individual symbol 0 standing for zero, the function symbol ′ denoting the successor function, propositional connectives, and quantifiers for both types of variables. Thus SC is a fraction of the restricted second order theory of natural numbers, or of the first order theory of real numbers. In fact, if predicates on natural numbers are interpreted as binary expansions of real numbers, it is easy to see that SC is equivalent to the first order theory of [Re, +, Pw, Nn], whereby Re, Pw, Nn are, respectively, the sets of non-negative reals, integral powers of 2, and natural numbers.

The polymerase chain reaction. A new method of using molecular genetics for medical diagnosis.

Abstract: THE development of molecular genetics, both as a self-contained field and as a body of techniques broadly useful in biologic investigation, has had a profound influence on medical research. The beneficiaries include every discipline in basic science and, at least indirectly, most clinical and applied medical disciplines. Certain technical milestones can be identified over the past several decades that have been particularly important in the progress of the field. One is the discovery of restriction endonucleases, which together with the development of DNA ligation and transformation procedures, led to the ability to clone and thus propagate genes of any organism . . .

Coronary morphologic and clinical determinants of procedural outcome with angioplasty for multivessel coronary disease. Implications for patient selection. Multivessel Angioplasty Prognosis Study Group.

Abstract: To assess the likelihood of procedural success in patients with multivessel coronary disease undergoing percutaneous coronary angioplasty, 350 consecutive patients (1,100 stenoses) from four clinical sites were evaluated. Eighteen variables characterizing the severity and morphology of each stenosis and 18 patient-related variables were assessed at a core angiographic laboratory and at the clinical sites. Most patients had Canadian Cardiovascular Society class III or IV angina (72%) and two-vessel coronary disease (78%). Left ventricular function was generally well preserved (mean ejection fraction, 58 +/- 12%; range, 18-85%) and 1.9 +/- 1.0 stenoses per patient had attempted percutaneous coronary angioplasty. Procedural success (less than or equal to 50% final diameter stenosis in one or more stenoses and no major ischemic complications) was achieved in 290 patients (82.8%), and an additional nine patients (2.6%) had a reduction in diameter stenosis by 20% or more with a final diameter stenosis 51-60% and were without major complications. Major ischemic complications (death, myocardial infarction, or emergency bypass surgery) occurred in 30 patients (8.6%). In-hospital mortality was 1.1%. Stepwise regression analysis determined that a modified American College of Cardiology/American Heart Association Task Force (ACC/AHA) classification of the primary target stenosis (with type B prospectively divided into type B1 [one type B characteristic] and type B2 [greater than or equal to two type B characteristics]) and the presence of diabetes mellitus were the only variables independently predictive of procedural outcome (target stenosis modified ACC/AHA score; p less than 0.001 for both success and complications; diabetes mellitus: p = 0.003 for success and p = 0.016 for complications). Analysis of success and complications on a per stenosis dilated basis showed, for type A stenoses, a 92% success and a 2% complication rate; for type B1 stenoses, an 84% success and a 4% complication rate; for type B2 stenoses, a 76% success and a 10% complication rate; and for type C stenoses, a 61% success and a 21% complication rate. The subdivision into types B1 and B2 provided significantly more information in this clinically important intermediate risk group than did the standard ACC/AHA scheme. The stenosis characteristics of chronic total occlusion, high grade (80-99% diameter) stenosis, stenosis bend of more than 60 degrees, and excessive tortuosity were particularly predictive of adverse procedural outcome. This improved scheme may improve clinical decision making and provide a framework on which to base meaningful subgroup analysis in randomized trials assessing the efficacy of percutaneous coronary angioplasty.

An eclectic theory of the choice of international entry mode

Abstract: The choice of entry mode into a foreign market has a major impact on the success of a firm's international operations. However, the existing literature on the entry mode decision has either presented a list of considerations without identifying underlying constructs, or treated each entry decision in isolation. Here, a unifying framework is developed. This framework identifies three underlying constructs that influence the entry mode decision. These constructs are linked to considerations that have been previously discussed in the literature. It is argued that a firm's choice of entry mode depends on the strategic relationship the firm envisages between operations in different countries. A particular entry decision cannot be viewed in isolation. It must be considered in relation to the overall strategic posture of the firm. Further, the paper argues that different variables often suggest different entry modes, and that resolving these differences involves accepting trade-offs.

Preprocessing and postprocessing for materials based on the homogenization method with adaptive finite element methods

Abstract: This paper discusses the homogenization method to determine the effective average elastic constants of linear elasticity of general composite materials by considering their microstructure. After giving a brief theory of the homogenization method, a finite element approximation is introduced with convergence study and corresponding error estimate. Applying these, computer programs PREMAT and POSTMAT are developed for preprocessing and postprocessing of material characterization of composite materials. Using these programs, the homogenized elastic constants for macroscopic stress analysis are obtained for typical composite materials to show their capability. Finally, the adaptive finite element method is introduced to improve the accuracy of the finite element approximation.

Tastes and Technology in a Two-Country Model of the Business Cycle: Explaining International Comovements

Abstract: Trade on international financial markets allows people to insure country-specific risk and smooth consumption intertemporally. Equilibrium models of business cycles with trade on global financial markets typically yield international consumption correlations near 1 and excessive volatility of investment. We incorporate nontraded goods in the model and find that the implications for aggregate consumption, investment, and the trade balance are consistent with business-cycle properties of industrialized countries. However, the model driven by technology shocks alone yields counterfactual implications for comovements between consumption and prices at the sectoral level. Taste shocks produce price - quantity relationships more consistent with the data. (JEL E30, F40)

Using dynamic programming for solving variational problems in vision: applications involving deformable models for contours and surfaces.

Abstract: Dynamic programming is discussed as an approach to solving variational problems in vision. Dynamic programming ensures global optimality of the solution, is numerically stable, and allows for hard constraints to be enforced on the behavior of the solution within a natural and straightforward structure. As a specific example of the approach's efficacy, applying dynamic programming to the energy-minimizing active contours is described. The optimization problem is set up as a discrete multistage decision process and is solved by a time-delayed discrete dynamic programming algorithm. A parallel procedure for decreasing computational costs is discussed. >

Using dynamic programming for solving variational problems in vision

Abstract: Dynamic programming is discussed as an approach to solving variational problems in vision. Dynamic programming ensures global optimality of the solution, is numerically stable, and allows for hard constraints to be enforced on the behavior of the solution within a natural and straightforward structure. As a specific example of the approach's efficacy, applying dynamic programming to the energy-minimizing active contours is described. The optimization problem is set up as a discrete multistage decision process and is solved by a time-delayed discrete dynamic programming algorithm. A parallel procedure for decreasing computational costs is discussed. >

Fiscal Paradise: Foreign Tax Havens and American Business

Abstract: The offshore tax haven affiliates of American corporations account for more than a quarter of US foreign investment, an nearly a third of the foreign profits of US firms. This paper analyzes the origins of this tax haven activity and its implications for the US and foreign governments. Based on the behavior of US fins in 1982, it appears that American companies report extraordinarily high profit rates on both their real and their financial investments in tax havens. We calculate from this behavior that the tax rate that maximizes tax revenue for a typical haven is around 6%. The revenue implications for the US are more complicated, since tax havens may ultimately enhance the ability of the US government to tax the foreign earnings of American companies.

Designing the national resident assessment instrument for nursing homes

Abstract: In response to the Omnibus Reconciliation Act of 1987 mandate for the development of a national resident assessment system for nursing facilities, a consortium of professionals developed the first major component of this system, the Minimum Data Set (MDS) for Resident Assessment and Care Screening. A two-state field trial tested the reliability of individual assessment items, the overall performance of the instrument, and the time involved in its application. The trial demonstrated reasonable reliability for 55% of the items and pinpointed redundancy of items and initial design of scales. On the basis of these analyses and clinical input, 40% of the original items were kept, 20% dropped, and 40% altered. The MDS provides a structure and language in which to understand long-term care, design care plans, evaluate quality, and describe the nursing facility population for planning and policy efforts.

Work Motivation and Satisfaction: Light at the End of the Tunnel

Abstract: After decades of research it is now possible to offer a coherent, data-based theory of work motivation and job satisfaction. The present model combines aspects of the following theories: goal setting, expectancy, social-cognitive, attribution, job characteristics, equity, and turnover-commitment. The resulting model is called the high performance cycle. It begins with organizational members being faced with high challenge or difficult goals. If high challenge is accompanied by high expectancy of success or self-efficacy, high performance results, given that there is: commitment to the goals, feedback, adequate ability, and low situational constraints. High performance is achieved through four mechanisms, direction of attention and action, effort, persistence, and the development of task strategies and plans. High performance, if rewarding, leads to job satisfaction, which in turn facilitates commitment to the organization and its goals. The model has implications for leadership, self-management, and educa...

Trying to Consume

Abstract: An important but relatively neglected area of consumer behavior—the pursuit of goals—is addressed. Two recent modifications of the Fishbein model are discussed, and an extension is introduced to better explain goal pursuit. Major revisions include (1) specification of three dimensions of attitude—toward success, failure, and the process of trying, (2) the incorporation of self-efficacy judgments as expectations of success and failure, and (3) refinement in the specificity of referents and their correspondence to reflect trying as the focal explanatory concept. Recency and frequency of past trying are independent variables in three models tested with weight loss data.

Age, socioeconomic status, and health.

Abstract: Analysts dispute what roles biomedical, psychosocial, and other factors play in determining the duration of morbidity and disability over the life course. Cross-sectional data from two national surveys of adults aged 25 years and over not only show, however, that age and socioeconomic status (SES) are significant predictors of self-reported physical health; they also demonstrate that the relation of age to health varies with SES features. Longitudinal research is needed to test the finding that enduring functional limitations in terms of time are actually compressed in higher SES groups. To improve well-being in our society, moreover, requires specifying why SES differences occur, and perhaps ultimately reducing socioeconomic inequality itself.

Role of tumor necrosis factor-alpha in the pathophysiologic alterations after hepatic ischemia/reperfusion injury in the rat.

Abstract: Cytokines are recognized as critical early mediators of organ injury. We attempted to determine whether or not severe hepatic ischemia/reperfusion injury results in tumor necrosis factor-alpha (TNF-alpha) release with subsequent local and systemic tissue injury. After 90 min of lobar hepatic ischemia, TNF was measurable during the reperfusion period in the plasma of all 14 experimental animals, with levels peaking between 9 and 352 pg/ml. Endotoxin was undetectable in the plasma of these animals. Pulmonary injury, as evidenced by a neutrophilic infiltrate, edema and intra-alveolar hemorrhage developed after hepatic reperfusion. The neutrophilic infiltrate was quantitated using a myeloperoxidase (MPO) assay; this demonstrated a significant increase in MPO after only 1 h of reperfusion. Anti-TNF antiserum pretreatment significantly reduced the pulmonary MPO after hepatic reperfusion. After a 12-h reperfusion period, there was histologic evidence of intra-alveolar hemorrhage and pulmonary edema. Morphometric assessment showed that pretreatment with anti-TNF antiserum was able to completely inhibit the development of pulmonary edema. Liver injury was quantitated by measuring serum glutamic pyruvic transaminase which showed peaks at 3 and 24 h. Anti-TNF antiserum pretreatment was able to significantly reduce both of these peak elevations. These data show that hepatic ischemia/reperfusion results in TNF production, and that this TNF is intimately associated with pulmonary and hepatic injury.

Category-Based Induction

Abstract: An argument is categorical if its premises and conclusion are of the form All members ofC have property F, where C is a natural category like FALCON or BIRD, and P remains the same across premises and conclusion. An example is Grizzly bears love onions. Therefore, all bears love onions. Such an argument is psychologically strong to the extent that belief in its premises engenders belief in its conclusion. A subclass of categorical arguments is examined, and the following hypothesis is advanced: The strength of a categorical argument increases with (a) the degree to which the premise categories are similar to the conclusion category and (b) the degree to which the premise categories are similar to members of the lowest level category that includes both the premise and the conclusion categories. A model based on this hypothesis accounts for 13 qualitative phenomena and the quantitative results of several experiments.