Journal of Information and Optimization Sciences 

About: Journal of Information and Optimization Sciences is an academic journal published by Taylor & Francis. The journal publishes majorly in the area(s): Computer science & Economic order quantity. It has an ISSN identifier of 0252-2667. Over the lifetime, 2216 publications have been published receiving 9447 citations. The journal is also known as: Journal of information and optimization sciences.

Ratio and Product Type Exponential Estimators

Abstract: This paper proposes new ratio and product type estimators for estimating the mean of the finite population using information on single auxiliary variable. The bias and mean square error of these estimators have been obtained. These estimators are compared for their precision with usual mean per unit, ratio and product estimators and are found to be more efficient in many practical situations. Further, it is shown that these estimators reduce to regression estimator.

Further Generalizations of Convexity in Mathematical Programming

Abstract: The Kuhn-Tucker conditions for the existence of solutions to inequality constrained minimization problems are sufficient conditions when all the functions involved are convex. Various concepts such as pseudo-convexity and quasi-convexity have been introduced for the purpose of weakening this limitation of convexity in mathematical programming. Still wider classes of functions are introduced in this paper and applied in Kunh-Tucker theory and in duality theory.

Improved extensions of the TOPSIS for group decisionmaking under fuzzy environment

Abstract: Chen [2] extended the TOPSIS to a fuzzy environment. In his work, a vertex method was proposed to measure the distance between two given triangular fuzzy numbers. He further applied the vertex method to measure the distance between the weighted normalized fuzzy ratings and the fuzzy positive (negative}-ideal solutions to complete the fuzzy TOPSIS model. Despite the merits of his work, this application is not reasonable. Because the weighted normalized fuzzy ratings are truly not triangular fuzzy numbers. To overcome the above shortcomings, we suggest an improved fuzzy TOPSIS model, where membership functions for the weighted normalized fuzzy ratings are presented. A simple method is also proposed for ranking fuzzy numbers with mean of relative areas. This ranking method is further applied to establish the proposed model. Illustrative examples demonstrate the merits of the proposed ranking method and the feasibility of the improved fuzzy TOPSIS model, respectively.

The relationship between service quality and customer satisfaction: the example of CJCU library

Abstract: The present paper, taking Chang Jung Christian University (CJCU) Library as an example, investigates the users' degree of importance and the performance provided by the library. This study explores overall user satisfaction as well. A questionnaire survey s conducted to reveal users' perspectives on service quality. Based on literature, servicequality has five dimensions, which are tangibles, responsiveness, reliability, assurance, and empathy. The results indicate that the overall service quality has a significantly positive effect on overall user satisfaction. Among these five dimensions except responsiveness, all of them have a significantly positive effect on overall user satisfaction. In addition, the top five important service quality features ranked by users are: collections, loaning and returning service, overall atmosphere, electronic database system, and online reservation and renewal. Furthermore, the perceived importance of service quality dimensions has no significant difference among institu...

Codes and groups

Abstract: In this paper codes with two control symbols, built over some classes of groups, are studied.