University of Missouri

About: University of Missouri is a education organization based out in Columbia, Missouri, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 41427 authors who have published 83598 publications receiving 2911437 citations. The organization is also known as: Mizzou & Missouri-Columbia.

A possibilistic approach to clustering

Abstract: The clustering problem is cast in the framework of possibility theory. The approach differs from the existing clustering methods in that the resulting partition of the data can be interpreted as a possibilistic partition, and the membership values can be interpreted as degrees of possibility of the points belonging to the classes, i.e., the compatibilities of the points with the class prototypes. An appropriate objective function whose minimum will characterize a good possibilistic partition of the data is constructed, and the membership and prototype update equations are derived from necessary conditions for minimization of the criterion function. The advantages of the resulting family of possibilistic algorithms are illustrated by several examples. >

A fuzzy K-nearest neighbor algorithm

Abstract: Classification of objects is an important area of research and application in a variety of fields. In the presence of full knowledge of the underlying probabilities, Bayes decision theory gives optimal error rates. In those cases where this information is not present, many algorithms make use of distance or similarity among samples as a means of classification. The K-nearest neighbor decision rule has often been used in these pattern recognition problems. One of the difficulties that arises when utilizing this technique is that each of the labeled samples is given equal importance in deciding the class memberships of the pattern to be classified, regardless of their `typicalness'. The theory of fuzzy sets is introduced into the K-nearest neighbor technique to develop a fuzzy version of the algorithm. Three methods of assigning fuzzy memberships to the labeled samples are proposed, and experimental results and comparisons to the crisp version are presented.

Guidelines for the use and interpretation of assays for monitoring autophagy in higher eukaryotes

Abstract: Research in autophagy continues to accelerate,(1) and as a result many new scientists are entering the field Accordingly, it is important to establish a standard set of criteria for monitoring macroautophagy in different organisms Recent reviews have described the range of assays that have been used for this purpose(2,3) There are many useful and convenient methods that can be used to monitor macroautophagy in yeast, but relatively few in other model systems, and there is much confusion regarding acceptable methods to measure macroautophagy in higher eukaryotes A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers of autophagosomes versus those that measure flux through the autophagy pathway; thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from fully functional autophagy that includes delivery to, and degradation within, lysosomes (in most higher eukaryotes) or the vacuole (in plants and fungi) Here, we present a set of guidelines for the selection and interpretation of the methods that can be used by investigators who are attempting to examine macroautophagy and related processes, as well as by reviewers who need to provide realistic and reasonable critiques of papers that investigate these processes This set of guidelines is not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to verify an autophagic response

Board of director involvement in restructuring: The effects of board versus managerial controls and characteristics

Abstract: Board of director involvement in restructuring reveals whether restructuring is brought on as an action by the board in its central oversight role or whether managers are purusing positive strategic action or correction Therefore, based on an integration of organization economics (agency theory and market for corporate control) and strategic management theory (internal control and strategic leadership contingencies), this research examines board involvement in restructuring Board involvement is hypothesized to be contingent on the governance mechanisms used by the board to monitor top management, control emphasis used by managers to process strategic information and board and managerial characteristics The basic premise of the paper is that, due to their oversight role, board members (especially outside directors) become involved in restructuring only when managerial strategy implementation appears to be deficient Top management team equity stakes are found to be negatively related to board involvement in restructuring, while outside director ownership is found to be positively related Emphasis on strategic controls by managers was found to be negatively related to board involvement in restructuring Top management team tenure and top management organizational tenure are negatively related to board involvement Outsider representation on the board is positively related to board involvement in restructuring, while board tenure was found to be unrelated Results imply that incentives to monitor (ownership) and emphasis on strategic controls reinforced by higher top management team tenure result in less board involvement in restructuring However, restructuring may be initiated by outsiders on the board when other governance and control mechanisms fail This implies a substitution process between governance tactics (ownership vs board monitoring) and internal controls (managerial vigilance)