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ABSTRACTThis research investigates how information asymmetry between the firm and its investors can influence supply chain disruptions. In such settings, these actors may be induced to take steps which exacerbate rather than ameliorate both the likelihood and impact of disruptions. By better understanding these mechanisms, managers and investors alike are better armed to avoid the costly consequences.

AbstractAchievement test results from the Third International Mathematics and Science Study (TIMSS) and the National Assessment of Educational Progress (NAEP) suggest that the performance of US students in science is not strong either in terms of international or national standards. Yet, the US is preceived as a world leader in standards‐based and "hands‐on" science reform. In this article I argue that the major policy issue confronting the science community that addresses this apparent disconnect is the development of an organizing principle that would serve to limit the number of essential topics, subordinating some topics in science standards to others. Furthermore, this organizing principle would weave the reduced set of topics into a sequence that is logical and that leads to an unfolding of a key story or stories in science that are intrinsically interesting to students and that provide the basis for understanding science by future literate citizens and not just the memorization of isolated facts to be forgotten when school finishes.

In the natural world, a number of visual cues indicate that an item is quickly approaching the perceiver. Binocular disparity is one cue for depth, and it has been demonstrated that abrupt changes in disparity, artificially unaccompanied by correlated depth cues, are capable of causing the perception of looming for the observer. An experiment involving 38 undergraduates, using a computer-controlled stereoscopic display, examined the ability of above-threshold changes in disparity (artificial looming) to facilitate response time and accuracy for observers engaged in an object-enumeration task within a cluttered display. Compared with performance using the same stimuli without disparity information (lateral motion), participants were more accurate regardless of the disparity level (9, 12, 24, or 48 minutes of arc) and faster at the two lowest levels of disparity. Participants showed the classic subitizing function, suggesting that target stimuli presented with motion information were segregated from otherwise identical distractor items. It is proposed that binocular disparity information can act as a valid location cuing method in stereoscopic computer displays in which form and color information are to be preserved.

Cover -- Contents -- Preface -- Acknowledgments -- Chapter 1 -- Potential Consequences Related to Differences in Content Coverage -- The American Myth of Educational Equality -- The Difference that Schooling Makes -- A Definition of Opportunity to Learn -- The Role of Individual Responsibility in Education -- The Need to Challenge the American Myth that Schooling is Equal for All -- Equality Versus Equity in Opportunities to Learn -- Teachers -- Instructional Materials -- Instructional Time -- School Funding -- The Role of OTL in Inequalities in American Education -- Part I -- Chapter 2 -- The Clash of Two Great Traditions -- The Consequences of Local Control of the Curriculum -- Content Variation in State Standards -- The Total Number of Topics Intended to Be Taught Across the States -- Intended Coverage of Specific Topics Across the States -- The Grade at Which Various Topics Are Covered -- Focus and Coherence of School Topics -- State Variation in Coherence and Focus -- Content Variation Across Local Districts -- The Total Number of Topics Intended to Be Covered -- The Grade at Which Various Topics Are Covered -- A Special Look at Algebra and Geometry -- Science Content Variation -- Content Variation in State Standards -- What District Standards Say About the Sciences -- The Consequences of State and Local Controlof the Curriculum -- Chapter 3 -- Social Class, Race, and Equality of Opportunity -- Variability in Learning Opportunities Related to Socioeconomic Status -- The Number of Mathematics Topics Covered -- The Grades at Which Topics Were Covered -- Inequalities Within the SES-Based Groups of Districts -- State-Based Versus SES-Based District Groupings -- Content Opportunities in Urban Districts -- Inequality in 8th-Grade Mathematics Among Districts -- Expectations Versus Implementation -- Chapter 4.

This paper uses PISA data to explore cross-national comparisons of mathematics performance and educational inequality, with a focus on those countries that are characterized by high PISA scores and greater equity. The authors discuss the dangers of giving too much attention to a single year's high performer on a given international assessment. Instead, they argue that the PISA and TIMSS should be analyzed with a more nuanced set of indicators and with greater sensitivity to long-term trends. This approach can help generate new research hypotheses, identify groups of countries worthy of detailed study, and yield fresh insights on educational policy.