Showing papers by "University of Illinois at Urbana–Champaign published in 2004"
20 Mar 2004
TL;DR: The design of the LLVM representation and compiler framework is evaluated in three ways: the size and effectiveness of the representation, including the type information it provides; compiler performance for several interprocedural problems; and illustrative examples of the benefits LLVM provides for several challenging compiler problems.
Abstract: We describe LLVM (low level virtual machine), a compiler framework designed to support transparent, lifelong program analysis and transformation for arbitrary programs, by providing high-level information to compiler transformations at compile-time, link-time, run-time, and in idle time between runs. LLVM defines a common, low-level code representation in static single assignment (SSA) form, with several novel features: a simple, language-independent type-system that exposes the primitives commonly used to implement high-level language features; an instruction for typed address arithmetic; and a simple mechanism that can be used to implement the exception handling features of high-level languages (and setjmp/longjmp in C) uniformly and efficiently. The LLVM compiler framework and code representation together provide a combination of key capabilities that are important for practical, lifelong analysis and transformation of programs. To our knowledge, no existing compilation approach provides all these capabilities. We describe the design of the LLVM representation and compiler framework, and evaluate the design in three ways: (a) the size and effectiveness of the representation, including the type information it provides; (b) compiler performance for several interprocedural problems; and (c) illustrative examples of the benefits LLVM provides for several challenging compiler problems.
4,841 citations
Book•
01 Jan 2004TL;DR: In this paper, the Kohn-Sham ansatz is used to solve the problem of determining the electronic structure of atoms, and the three basic methods for determining electronic structure are presented.
Abstract: Preface Acknowledgements Notation Part I. Overview and Background Topics: 1. Introduction 2. Overview 3. Theoretical background 4. Periodic solids and electron bands 5. Uniform electron gas and simple metals Part II. Density Functional Theory: 6. Density functional theory: foundations 7. The Kohn-Sham ansatz 8. Functionals for exchange and correlation 9. Solving the Kohn-Sham equations Part III. Important Preliminaries on Atoms: 10. Electronic structure of atoms 11. Pseudopotentials Part IV. Determination of Electronic Structure, The Three Basic Methods: 12. Plane waves and grids: basics 13. Plane waves and grids: full calculations 14. Localized orbitals: tight binding 15. Localized orbitals: full calculations 16. Augmented functions: APW, KKR, MTO 17. Augmented functions: linear methods Part V. Predicting Properties of Matter from Electronic Structure - Recent Developments: 18. Quantum molecular dynamics (QMD) 19. Response functions: photons, magnons ... 20. Excitation spectra and optical properties 21. Wannier functions 22. Polarization, localization and Berry's phases 23. Locality and linear scaling O (N) methods 24. Where to find more Appendixes References Index.
2,690 citations
TL;DR: A novel frequent-pattern tree (FP-tree) structure is proposed, which is an extended prefix-tree structure for storing compressed, crucial information about frequent patterns, and an efficient FP-tree-based mining method, FP-growth, is developed for mining the complete set of frequent patterns by pattern fragment growth.
Abstract: Mining frequent patterns in transaction databases, time-series databases, and many other kinds of databases has been studied popularly in data mining research. Most of the previous studies adopt an Apriori-like candidate set generation-and-test approach. However, candidate set generation is still costly, especially when there exist a large number of patterns and/or long patterns.
In this study, we propose a novel frequent-pattern tree (FP-tree) structure, which is an extended prefix-tree structure for storing compressed, crucial information about frequent patterns, and develop an efficient FP-tree-based mining method, FP-growth, for mining the complete set of frequent patterns by pattern fragment growth. Efficiency of mining is achieved with three techniques: (1) a large database is compressed into a condensed, smaller data structure, FP-tree which avoids costly, repeated database scans, (2) our FP-tree-based mining adopts a pattern-fragment growth method to avoid the costly generation of a large number of candidate sets, and (3) a partitioning-based, divide-and-conquer method is used to decompose the mining task into a set of smaller tasks for mining confined patterns in conditional databases, which dramatically reduces the search space. Our performance study shows that the FP-growth method is efficient and scalable for mining both long and short frequent patterns, and is about an order of magnitude faster than the Apriori algorithm and also faster than some recently reported new frequent-pattern mining methods.
2,567 citations
TL;DR: In this paper, the authors systematically review and integrate empirical research that has examined the personal and contextual characteristics that enhance or stifle employee creativity in the workplace, and discuss possible determinants of employee creativity that have received little research attention.
2,273 citations
TL;DR: This article presented a bottom-up estimate of uncertainties in source strength by combining uncertainties in particulate matter emission factors, emission characterization, and fuel use, with uncertainty ranges of 4.3-22 Tg/yr for BC and 17-77 Tg /yr for OC.
Abstract: [1] We present a global tabulation of black carbon (BC) and primary organic carbon (OC) particles emitted from combustion. We include emissions from fossil fuels, biofuels, open biomass burning, and burning of urban waste. Previous ‘‘bottom-up’’ inventories of black and organic carbon have assigned emission factors on the basis of fuel type and economic sector alone. Because emission rates are highly dependent on combustion practice, we consider combinations of fuel, combustion type, and emission controls and their prevalence on a regional basis. Central estimates of global annual emissions are 8.0 Tg for black carbon and 33.9 Tg for organic carbon. These estimates are lower than previously published estimates by 25–35%. The present inventory is based on 1996 fuel-use data, updating previous estimates that have relied on consumption data from 1984. An offset between decreased emission factors and increased energy use since the base year of the previous inventory prevents the difference between this work and previous inventories from being greater. The contributions of fossil fuel, biofuel, and open burning are estimated as 38%, 20%, and 42%, respectively, for BC, and 7%, 19%, and 74%, respectively, for OC. We present a bottom-up estimate of uncertainties in source strength by combining uncertainties in particulate matter emission factors, emission characterization, and fuel use. The total uncertainties are about a factor of 2, with uncertainty ranges of 4.3–22 Tg/yr for BC and 17–77 Tg/yr for OC. Low-technology combustion contributes greatly to both the emissions and the uncertainties. Advances in emission characterization for small residential, industrial, and mobile sources and topdown analysis combining field measurements and transport modeling with iterative inventory development will be required to reduce the uncertainties further. INDEX TERMS: 0305 Atmospheric Composition and Structure: Aerosols and particles (0345, 4801); 0322 Atmospheric Composition and Structure: Constituent sources and sinks; 0345 Atmospheric Composition and Structure: Pollution—urban and regional (0305); 0360 Atmospheric Composition and Structure: Transmission and scattering of radiation; 0365 Atmospheric Composition and Structure: Troposphere—composition and chemistry; KEYWORDS: emission, black carbon, organic carbon, fossil fuel, biofuel, biomass burning
2,180 citations
TL;DR: In this article, a general force field, CLAYFF, was developed for the simulation of hydrated and multicomponent mineral systems and their interfaces with aqueous solutions, and the potentials were derived from parametrizations incorporating structural and spectroscopic data for a variety of simple hydrated compounds.
Abstract: The fate of chemical and radioactive wastes in the environment is related to the ability of natural phases to attenuate and immobilize contaminants through chemical sorption and precipitation processes. Our understanding of these complex processes at the atomic level is provided by a few experimental and analytical methods such as X-ray absorption and NMR spectroscopies. However, due to complexities in the structure and composition of clay and other hydrated minerals, and the inherent uncertainties of the experimental methods, it is important to apply theoretical molecular models for a fundamental atomic-level understanding, interpretation, and prediction of these phenomena. In this effort, we have developed a general force field, CLAYFF, suitable for the simulation of hydrated and multicomponent mineral systems and their interfaces with aqueous solutions. Interatomic potentials were derived from parametrizations incorporating structural and spectroscopic data for a variety of simple hydrated compounds. A...
2,163 citations
TL;DR: It is argued that economic indicators were extremely important in the early stages of economic development, when the fulfillment of basic needs was the main issue and differences in well-being are less frequently due to income, and are more frequentlyDue to factors such as social relationships and enjoyment at work.
Abstract: Policy decisions at the organizational, corporate, and governmental levels should be more heavily influenced by issues related to well-being—people’s evaluations and feelings about their lives. Domestic policy currently focuses heavily on economic outcomes, although economic indicators omit, and even mislead about, much of what society values. We show that economic indicators have many shortcomings, and that measures of well-being point to important conclusions that are not apparent from economic indicators alone. For example, although economic output has risen steeply over the past decades, there has been no rise in life satisfaction during this period, and there has been a substantial increase in depression and distrust. We argue that economic indicators were extremely important in the early stages of economic development, when the fulfillment of basic needs was the main issue. As societies grow wealthy, however, differences in well-being are less frequently due to income, and are more frequently due to factors such as social relationships and enjoyment at work.
2,114 citations
TL;DR: In this paper, the authors empirically estimate the sensitivity of cash using a large sample of manufacturing firms over the 1971 to 2000 period and find robust support for their theory, and hypothesize that constrained firms should have a positive cash flow sensitivity, while unconstrained firms' cash savings should not be systematically related to cash flows.
Abstract: We model a firm’s demand for liquidity to develop a new test of the effect of financial constraints on corporate policies. The effect of financial constraints is captured by the firm’s propensity to save cash out of cash flows (the cash flow sensitivity of cash). We hypothesize that constrained firms should have a positive cash flow sensitivity of cash, while unconstrained firms’ cash savings should not be systematically related to cash flows. We empirically estimate the cash flow sensitivity of cash using a large sample of manufacturing firms over the 1971 to 2000 period and find robust support for our theory. TWO IMPORTANT AREAS OF RESEARCH in corporate finance are the effects of financial constraints on firm behavior and the manner in which firms perform financial management. These two issues, although often studied separately, are fundamentally linked. As originally proposed by Keynes (1936), a major advantage of a liquid balance sheet is that it allows firms to undertake valuable projects when they arise. However, Keynes also argued that the importance of balance sheet liquidity is influenced by the extent to which firms have access to external capital markets (p. 196). If a firm has unrestricted access to external capital— that is, if a firm is financially unconstrained—there is no need to safeguard against future investment needs and corporate liquidity becomes irrelevant. In contrast, when the firm faces financing frictions, liquidity management may become a key issue for corporate policy. Despite the link between financial constraints and corporate liquidity demand, the literature that examines the effects of financial constraints on firm behavior has traditionally focused on corporate investment demand. 1 In an influential paper, Fazzari, Hubbard, and Petersen (1988) propose that when firms face financing constraints, investment spending will vary with the availability of internal funds, rather than just with the availability of positive net present
2,034 citations
TL;DR: In this article, the authors report on the findings of an inductive, interpretive case study of organizational identity change in the spin-off of a Fortune 100 company's top-performing organizational unit into an independen...
Abstract: We report on the findings of an inductive, interpretive case study of organizational identity change in the spin-off of a Fortune 100 company's top-performing organizational unit into an independen...
1,702 citations
TL;DR: This method, which eliminates exposure of the fragile organic surface to the hazards of conventional processing, enables fabrication of rubrene transistors with charge carrier mobilities as high as ∼15 cm2/V·s and subthreshold slopes as low as 2nF·V/decade·cm2.
Abstract: We introduce a method to fabricate high-performance field-effect transistors on the surface of freestanding organic single crystals. The transistors are constructed by laminating a monolithic elastomeric transistor stamp against the surface of a crystal. This method, which eliminates exposure of the fragile organic surface to the hazards of conventional processing, enables fabrication of rubrene transistors with charge carrier mobilities as high as approximately 15 cm2/V.s and subthreshold slopes as low as 2nF.V/decade.cm2. Multiple relamination of the transistor stamp against the same crystal does not affect the transistor characteristics; we exploit this reversibility to reveal anisotropic charge transport at the basal plane of rubrene.
1,593 citations
TL;DR: Although trends agree with parallel summaries of enclosure studies, important quantitative differences emerge that have important implications both for predicting the future terrestrial biosphere and understanding how crops may need to be adapted to the changed and changing atmosphere.
Abstract: Atmospheric CO(2) concentration ([CO(2)]) is now higher than it was at any time in the past 26 million years and is expected to nearly double during this century. Terrestrial plants with the C(3) photosynthetic pathway respond in the short term to increased [CO(2)] via increased net photosynthesis and decreased transpiration. In the longer term this increase is often offset by downregulation of photosynthetic capacity. But much of what is currently known about plant responses to elevated [CO(2)] comes from enclosure studies, where the responses of plants may be modified by size constraints and the limited life-cycle stages that are examined. Free-Air CO(2) Enrichment (FACE) was developed as a means to grow plants in the field at controlled elevation of CO(2) under fully open-air field conditions. The findings of FACE experiments are quantitatively summarized via meta-analytic statistics and compared to findings from chamber studies. Although trends agree with parallel summaries of enclosure studies, important quantitative differences emerge that have important implications both for predicting the future terrestrial biosphere and understanding how crops may need to be adapted to the changed and changing atmosphere.
TL;DR: It is demonstrated for the first time to the authors' knowledge, in humans that increases in cardiovascular fitness results in increased functioning of key aspects of the attentional network of the brain during a cognitively challenging task.
Abstract: Cardiovascular fitness is thought to offset declines in cognitive performance, but little is known about the cortical mechanisms that underlie these changes in humans. Research using animal models shows that aerobic training increases cortical capillary supplies, the number of synaptic connections, and the development of new neurons. The end result is a brain that is more efficient, plastic, and adaptive, which translates into better performance in aging animals. Here, in two separate experiments, we demonstrate for the first time to our knowledge, in humans that increases in cardiovascular fitness results in increased functioning of key aspects of the attentional network of the brain during a cognitively challenging task. Specifically, highly fit (Study 1) or aerobically trained (Study 2) persons show greater task-related activity in regions of the prefrontal and parietal cortices that are involved in spatial selection and inhibitory functioning, when compared with low-fit (Study 1) or nonaerobic control (Study 2) participants. Additionally, in both studies there exist groupwise differences in activation of the anterior cingulate cortex, which is thought to monitor for conflict in the attentional system, and signal the need for adaptation in the attentional network. These data suggest that increased cardiovascular fitness can affect improvements in the plasticity of the aging human brain, and may serve to reduce both biological and cognitive senescence in humans.
TL;DR: In this paper, a general approach to estimating quantile regression models for longitudinal data is proposed employing l 1 regularization methods, based on the penalized least squares interpretation of the classical random effects estimator.
24 May 2004
TL;DR: This paper proposes a medium access control (MAC) protocol for ad hoc wireless networks that utilizes multiple channels dynamically to improve performance and solves the multi-channel hidden terminal problem using temporal synchronization.
Abstract: This paper proposes a medium access control (MAC) protocol for ad hoc wireless networks that utilizes multiple channels dynamically to improve performance. The IEEE 802.11 standard allows for the use of multiple channels available at the physical layer, but its MAC protocol is designed only for a single channel. A single-channel MAC protocol does not work well in a multi-channel environment, because of the multi-channel hidden terminal problem . Our proposed protocol enables hosts to utilize multiple channels by switching hannels dynamically, thus increasing network throughput. The protocol requires only one transceiver per host, but solves the multi-channel hidden terminal problem using temporal synchronization. Our scheme improves network throughput signifiantly, especially when the network is highly congested. The simulation results show that our protocol successfully exploits multiple hannels to achieve higher throughput than IEEE 802.11. Also, the performance of our protocol is comparable to another multi-hannel MAC protocol that requires multiple transceivers per host. Since our protocol requires only one transceiver per host, it an be implemented with a hardware complexity comparable to IEEE 802.11.
TL;DR: The authors conducted a meta-analysis of conscientiousness-related traits and the leading behavioral contributors to mortality in the United States to demonstrate the importance ofcientiousness' contribution to the health process through its relationship to health-related behaviors.
Abstract: Previous research has established conscientiousness as a predictor of longevity (H. S. Friedman et al., 1993; L. R. Martin & H. S. Friedman, 2000). To better understand this relationship, the authors conducted a meta-analysis of conscientiousness-related traits and the leading behavioral contributors to mortality in the United States (tobacco use, diet and activity patterns, excessive alcohol use, violence, risky sexual behavior, risky driving, suicide, and drug use). Data sources were located by combining conscientiousness-related terms and relevant health-related behavior terms in database searches as well as by retrieving dissertations and requesting unpublished data from electronic mailing lists. The resulting database contained 194 studies that were quantitatively synthesized. Results showed that conscientiousness-related traits were negatively related to all risky health-related behaviors and positively related to all beneficial health-related behaviors. This study demonstrates the importance of conscientiousness' contribution to the health process through its relationship to health-related behaviors.
TL;DR: In this paper, the adoption of liberal economic practices is highly clustered both temporally and spatially, and the authors hypothesize that this clustering might be due to processes of policy diffusion.
Abstract: One of the most important developments over the past three decades has been the spread of liberal economic ideas and policies throughout the world. These policies have affected the lives of millions of people, yet our most sophisticated political economy models do not adequately capture influences on these policy choices. Evidence suggests that the adoption of liberal economic practices is highly clustered both temporally and spatially. We hypothesize that this clustering might be due to processes of policy diffusion. We think of diffusion as resulting from one of two broad sets of forces: one in which mounting adoptions of a policy alter the benefits of adopting for others and another in which adoptions provide policy relevant information about the benefits of adopting. We develop arguments within these broad classes of mechanisms, construct appropriate measures of the relevant concepts, and test their effects on liberalization and restriction of the current account, the capital account, and the exchange rate regime. Our findings suggest that domestic models of foreign economic policy making are insufficient. The evidence shows that policy transitions are influenced by international economic competition as well as the policies of a country's sociocultural peers. We interpret the latter influence as a form of channeled learning reflecting governments' search for appropriate models for economic policy.
TL;DR: In this article, the authors tried to build a conceptual model, in which both dimension of the tourist experience are integrated as a structured and interrelated whole, and the position and role of each experiential component such as eating, sleeping, transportation and so on in tourism can be more clearly understood in terms of this model.
30 Aug 2004
TL;DR: This paper presents a simple fluid model and considers the built-in incentive mechanism of BitTorrent and its effect on network performance, and provides numerical results based on both simulations and real traces obtained from the Internet.
Abstract: In this paper, we develop simple models to study the performance of BitTorrent, a second generation peer-to-peer (P2P) application. We first present a simple fluid model and study the scalability, performance and efficiency of such a file-sharing mechanism. We then consider the built-in incentive mechanism of BitTorrent and study its effect on network performance. We also provide numerical results based on both simulations and real traces obtained from the Internet.
TL;DR: In this paper, the authors identify research issues and gaps in existing knowledge on buyers' perceptions of price fairness, and conclude with guidelines for managerial practice for price fairness in the context of pricing.
Abstract: Recent news coverage on pricing portrays the importance of price fairness. This article conceptually integrates the theoretical foundations of fairness perceptions and summarizes empirical findings on price fairness. The authors identify research issues and gaps in existing knowledge on buyers’ perceptions of price fairness. The article concludes with guidelines for managerial practice.
TL;DR: In this article, a review of colloidal processing of ceramics is presented with an emphasis on interparticle forces, suspension rheology, consolidation techniques, and drying behavior.
Abstract: Colloidal processing of ceramics is reviewed with an emphasis on interparticle forces, suspension rheology, consolidation techniques, and drying behavior. Particular attention is given to the scientific concepts that underpin the fabrication of particulate-derived ceramic components. The complex interplay between suspension stability and its structural evolution during colloidal processing is highlighted.
TL;DR: A database of 575 individual faces ranging from ages 18 to 93 is described, developed to be more representative of age groups across the lifespan, with a special emphasis on recruiting older adults.
Abstract: Faces constitute a unique and widely used category of stimuli. In spite of their importance, there are few collections of faces for use in research, none of which adequately represent the different ages of faces across the lifespan. This lack of a range of ages has limited the majority of researchers to using predominantly young faces as stimuli even when their hypotheses concern both young and old participants. We describe a database of 575 individual faces ranging from ages 18 to 93. Our database was developed to be more representative of age groups across the lifespan, with a special emphasis on recruiting older adults. The resulting database has faces of 218 adults age 18-29, 76 adults age 30-49, 123 adults age 50-69, and 158 adults age 70 and older. These faces may be acquired for research purposes from http://agingmind.cns.uiuc.edu/facedb/. This will allow researchers interested in using facial stimuli access to a wider age range of adult faces than has previously been available.
TL;DR: It has been said that people with autism suffer from a lack of “central coherence,” the cognitive ability to bind together a jumble of separate features into a single, coherent object or concept.
Abstract: It has been said that people with autism suffer from a lack of “central coherence,” the cognitive ability to bind together a jumble of separate features into a single, coherent object or concept ([Frith, 1989][1]). Ironically, the same can be said of the field of autism research, which all too
TL;DR: This paper reviews theory and methodology that have been developed to cope with the complexity of optimization problems under uncertainty and discusses and contrast the classical recourse-based stochastic programming, robust stochastics programming, probabilistic (chance-constraint) programming, fuzzy programming, and stochastically dynamic programming.
Kevork N. Abazajian1, Jennifer K. Adelman-McCarthy2, Marcel A. Agüeros3, Sahar S. Allam4 +162 more•Institutions (41)
TL;DR: The second data release of the Sloan Digital Sky Survey (SDSS) as mentioned in this paper is the most recent data set to be publicly available, which consists of 3.5 million unique objects, 367,360 spectra of galaxies, quasars, stars, and calibrating blank sky patches selected over 2627 deg2 of this area.
Abstract: The Sloan Digital Sky Survey (SDSS) has validated and made publicly available its Second Data Release. This data release consists of 3324 deg2 of five-band (ugriz) imaging data with photometry for over 88 million unique objects, 367,360 spectra of galaxies, quasars, stars, and calibrating blank sky patches selected over 2627 deg2 of this area, and tables of measured parameters from these data. The imaging data reach a depth of r ≈ 22.2 (95% completeness limit for point sources) and are photometrically and astrometrically calibrated to 2% rms and 100 mas rms per coordinate, respectively. The imaging data have all been processed through a new version of the SDSS imaging pipeline, in which the most important improvement since the last data release is fixing an error in the model fits to each object. The result is that model magnitudes are now a good proxy for point-spread function magnitudes for point sources, and Petrosian magnitudes for extended sources. The spectroscopy extends from 3800 to 9200 A at a resolution of 2000. The spectroscopic software now repairs a systematic error in the radial velocities of certain types of stars and has substantially improved spectrophotometry. All data included in the SDSS Early Data Release and First Data Release are reprocessed with the improved pipelines and included in the Second Data Release. Further characteristics of the data are described, as are the data products themselves and the tools for accessing them.
TL;DR: In this paper, the authors take stock of the large body of extant research and provide a systematic assessment of empirical evidence and conclude that a more thorough empirical grounding of the theory's foundation is crucial to its future development, and offer several strategies for doing this.
Abstract: Transaction cost economics (TCE) is one of the leading perspectives in management and organizational studies, yet debate continues regarding its empirical support. In this paper, we take stock of the large body of extant research and provide a systematic assessment of empirical evidence. In all, 308 statistical tests from 63 articles, selected according to a set of clear criteria, were examined across various dimensions. We assess not only the level of empirical support for the theory, but also the degree of paradigm consensus present in the empirical literature. Our analysis shows that results are mixed: while we found support in some areas (e.g., with regard to asset specificity), we also found considerable disagreement on how to operationalize some of TCE's central constructs and propositions, and relatively low levels of empirical support in other core areas (e.g., surrounding uncertainty and performance). We conclude that a more thorough empirical grounding of the theory's foundation is crucial to its future development, and offer several strategies for doing this. Copyright © 2003 John Wiley & Sons, Ltd.
TL;DR: The air-gap field-effect technique enabled realization of the intrinsic (not limited by static disorder) polaronic transport on the surface of rubrene (C42H28) crystals over a wide temperature range.
Abstract: The air-gap field-effect technique enabled realization of the intrinsic (not limited by static disorder) polaronic transport on the surface of rubrene (C42H28) crystals over a wide temperature range. The signatures of this intrinsic transport are the anisotropy of the carrier mobility, mu, and the growth of mu with cooling. Anisotropy of mu vanishes in the activation regime at low temperatures, where the transport is dominated by shallow traps. The deep traps, introduced by x-ray radiation, increase the field-effect threshold without affecting mu, an indication that the filled traps do not scatter polarons.
TL;DR: For instance, this paper found that self-beliefs are associated with a small, favorable influence on academic achievement, with an average standardized path or regression coefficient of.08 for self belief as a predictor of later achievement.
Abstract: There has been extensive debate among scholars and practitioners concerning whether self-beliefs influence academic achievement. To address this question, findings of longitudinal studies investigating the relation between self-beliefs and achievement were synthesized using meta-analysis. Estimated effects are consistent with a small, favorable influence of positive self-beliefs on academic achievement, with an average standardized path or regression coefficient of .08 for self-beliefs as a predictor of later achievement, controlling for initial levels of achievement. Stronger effects of self-beliefs are evident when assessing self-beliefs specific to the academic domain and when measures of self-beliefs and achievement are matched by domain (e.g., same subject area). Under these conditions, the relation of self-beliefs to later achievement meets or exceeds Cohen's (1988) definition of a small effect size.
TL;DR: This review underscores how small structural changes in personal environments can reduce the unknowing overconsumption of food and redirecting the focus of investigations to the psychological mechanisms behind consumption will raise the profile and impact of research.
Abstract: ▪ Abstract Package size, plate shape, lighting, socializing, and variety are only a few of the environmental factors that can influence the consumption volume of food far more than most people realize. Although such environmental factors appear unrelated, they generally influence consumption volume by inhibiting consumption monitoring and by suggesting alternative consumption norms. For researchers, this review suggests that redirecting the focus of investigations to the psychological mechanisms behind consumption will raise the profile and impact of research. For health professionals, this review underscores how small structural changes in personal environments can reduce the unknowing overconsumption of food.
TL;DR: In this article, the authors show that the relationship between capital spending and cash flows is non-monotonic in the degree of tangibility of constrained firms' assets, and that asset tangibility itself may determine whether a firm faces credit constraints - firms with more tangible assets may have greater access to external funds.
Abstract: When firms are able to pledge their assets as collateral, investment and borrowing become endogenous: pledgeable assets support more borrowings that in turn allow for further investment in pledgeable assets. We show that this credit multiplier has an important impact on investment when firms face credit constraints: investment-cash flow sensitivities are increasing in the degree of tangibility of constrained firms' assets. If firms are unconstrained, however, investment-cash flow sensitivities are unaffected by asset tangibility. Crucially, asset tangibility itself may determine whether a firm faces credit constraints - firms with more tangible assets may have greater access to external funds. This implies that the relationship between capital spending and cash flows is non-monotonic in the firm's asset tangibility. Our theory allows us to use a differences-in-differences approach to identify the effect of financing frictions on corporate investment: we compare the differential (marginal) effect of asset tangibility on the sensitivity of investment to cash flow across different regimes of financial constraints. We implement this testing strategy on a large sample of manufacturing firms drawn from COMPUSTAT between 1985 and 2000. Our tests allow for the endogeneity of the firm's credit status, with asset tangibility influencing whether a firm is classified as credit constrained or unconstrained in a switching regression framework. The data strongly support our hypothesis about the role of asset tangibility on corporate investment under financial constraints.
Book•
14 Jan 2004TL;DR: The 2019 Richard M. Kalish Innovative Publication Book Award 2019 as discussed by the authors provides easily accessible and usable guidelines for practitioners in the design community for older adults, including an updated overview of the demographic characteristics of older adult populations and the scientific knowledge base of the aging process relevant to design.
Abstract: Winner of the 2019 Richard M. Kalish Innovative Publication Book Award 2019 – Gerontological Society of America
This new edition provides easily accessible and usable guidelines for practitioners in the design community for older adults. It includes an updated overview of the demographic characteristics of older adult populations and the scientific knowledge base of the aging process relevant to design. New chapters include Existing and Emerging Technologies, Work and Volunteering, Social Engagement, and Leisure Activities. Also included is basic information on user-centered design and specific recommendations for conducting research with older adults.
Features
Focuses on design for diverse groups of older adults
Introduces the latest scientific advances, but is easily accessible to practitioners and students
Offers an emphasis on existing and emerging technologies within everyday contexts and activities
Includes many examples of everyday activities and contexts, as well as new chapters
Presents a new conceptual model linking design principles across a broad range of topics