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The epistemology of testimony has experienced a growth in interest over the last twenty-five years that has been matched by few, if any, other areas of philosophy. Testimony: A Philosophical Introduction provides an epistemology of testimony that surveys this rapidly growing research area while incorporating a discussion of relevant empirical work from social and developmental psychology, as well as from the interdisciplinary study of knowledge-creation in groups. The past decade has seen a number of scholarly monographs on the epistemology of testimony, but there is a dearth of books that survey the current field. This book fills that gap, assessing the strengths and weaknesses of all major competing theories. All chapters conclude with Suggestions for Further Reading and Discussion Questions.

Abstract: "We examine the computational complexity of cartographic label placement, a problem derived from the cartographer's task of placing text labels adjacent to map features in such a way as to minimize overlaps with other labels and map features. Cartographic label placement is one of the most time-consuming tasks in the production of maps. Consequently, several attempts have been made to automate the label- placement task for some or all classes of cartographic features (punctual, linear, or areal features), but all previously published algorithms for the most basic task -- point-feature-label placement -- either exhibit worst- case exponential time complexity, or incorporate incomplete heuristics that may fail to find an admissible labeling even when one exists.

Abstract: "A major factor affecting the clarity of graphical displays that include text labels is the degree to which labels obscure display features (including other labels) as a result of spatial overlap. Point-feature label placement (PFLP) is the problem of placing text labels adjacent to point features on a map or diagram so as to maximize legibility. This problem occurs frequently in the production of many types of informational graphics, though it arises most often in automated cartography. In this paper we present a comprehensive treatment of the PFLP problem, viewed as a type of combinatorial optimization problem. Complexity analysis reveals that the basic PFLP problem and most interesting variants of it are NP-hard. We review these results briefly. These negative results help inform a survey of previously reported algorithms for PFLP; not surprisingly, all such algorithms either have exponential time complexity or are incomplete. To solve the PFLP problem in practice, then, we must rely on good heuristic methods. We propose two new methods, one based on a discrete form of gradient descent, the other on simulated annealing, and report on a series of empirical tests comparing these and the other known algorithms for the problem. Our results indicate that the simulated annealing approach to PFLP is superior to all existing methods, regardless of label density."

This notation is used in reformulating the layout task as a constrained-optimization problem in which constraints are derived from a visual-organization specification and optimality criteria are derived from layout-aesthetic considerations. Two new heuristic algorithms are presented for this version of the layout problem: one algorithm uses a rule-based strategy for computing a layout; the other is a massively parallel genetic algorithm. We demonstrate the capabilities of the two algorithms by testing them on a variety of network-diagram-layout problems."