Barbara Gładysz

The Shapley Value in Fuzzy Simple Cooperative Games.

This article presents an analysis of the Shapley value of simple cooperative games in situations where the weights of the players and the majority required to accept a decision (in the form of a winning coalition) are given by fuzzy numbers. We propose a modification of the concept of the additivity of the payoff function which is necessary in this framework.

Behavioural Aspects of Communication in the Management Process of IT Projects

The paper presents the results of research on the significance of communication in project teams, especially its behavioral aspects influencing the success or failure of an Information Technology Project (IT project). The holistic approach to the issue of communication, apart from the commonly indicated success and failure factors of such projects, also encompasses such issues as team work culture, its size, the achieved confidence level and mutual kindness. The work presents the current state of knowledge and the results of own research on impact factors in communication quality in IT projects. The authors own work comprised the formulation of research hypotheses related to selected factors influencing IT projects in various economy sectors and next the preparation and conduction of surveys (among project managers, leaders and team members both on the side of service providers and customers) and also proving the presented hypotheses.

Selection of IT projects to be implemented in an organisation to maximise their success probability

Abstract The paper proposes criteria to be used in a decision support system which should help to assess the success probability of IT projects considered for implementation, in order to help to make the decision whether to accept the project or not. The criteria used are both of a quantitative and subjective (qualitative) nature. They are identified on the basis of a sample of IT projects implemented in Poland, a questionnaire and the application of classification tree methods.

Group Approximation of Task Duration and Time Buffers in Scrum

Expansion of modern IT technologies, which took place last years, caused a significant increase in software projects. Those projects are quite often complex venture burdened with high risk. Nowadays, a large number of software projects is managed using Scrum framework. In Scrum, where people form self-organizing team, group decisions became an essential element of the project, which plays an important role to create time approximation or to manage potential risks. This paper focuses on group decisions, temporal aspects of estimation and risk management in Scrum project. In article we present conceptual model of extension Scrum framework by risk management process in aspect of project time estimation. Proposed model contains time buffers based on mixture probability distribution, which improve Scrum framework in terms of group estimation. We also depict case study which presents time approximation process which took place in one of a Scrum project.

Multicriteria Transportation Problems with Fuzzy Parameters

In the classical transportation problem, it is assumed that the transportation costs are known constants. In practice, however, transport costs depend on weather, road and technical conditions. The concept of fuzzy numbers is one approach to modeling the uncertainty associated with such factors. There have been a large number of papers in which models of transportation problems with fuzzy parameters have been presented. Just as in classical models, these models are constructed under the assumption that the total transportation costs are minimized. This article proposes two models of a transportation problem where decisions are based on two criteria. According to the first model, the unit transportation costs are fuzzy numbers. Decisions are based on minimizing both the possibilistic expected value and the possibilistic variance of the transportation costs. According to the second model, all of the parameters of the transportation problem are assumed to be fuzzy. The optimization criteria are the minimization of the possibilistic expected values of the total transportation costs and minimization of the total costs related to shortages (in supply or demand). In addition, the article defines the concept of a truncated fuzzy number, together with its possibilistic expected value. Such truncated numbers are used to define how large shortages are. Some illustrative examples are given.

Fuzzy-probabilistic PERT

Using PERT (Program evaluation and review technique), one assumes that the time required to carry out the individual tasks in a project can be approximated using a beta distribution. It is assumed that the parameters of these distributions (the minimum, maximum and most likely times) are estimated by experts in accordance with the properties of the beta distribution. However, this is not always the case. This article shows how one may analyse the time required to carry out a task. Two approaches to describing uncertainty regarding the duration of tasks are used: probabilistic and fuzzy. This article proposes a mixture of a beta probability distribution with a generative probability distribution to describe the duration of a task. An illustrative examples are given.