Utility-based reputation model for VO in GRIDs

In this paper we extend the existing utility-based reputation model for VOs in Grids by incorporating a statistical model of user behaviour (SMUB) that was previously developed for computer networks and distributed systems, and different functions to address threats scenarios in the area of trust and reputation management. These modifications include: assigning initial reputation to a new entity in VO, capturing alliance between consumer and resource, time decay function, and score function.В данной статье предложена модификация существующей модели репутаций для виртуальных организаций в Grid-системах, которая основана на оценке функции полезности. Модификация модели состоит в добавлении статистической модели поведения пользователя, которая ранее была разработана для компьютерных сетей и распределенных систем, а также компонентов, которые позволяют противостоять угрозам в области управления доверием и репутацией. К числу этих компонентов относятся: механизм присвоения начальной репутации для новых субъектов виртуальной организации; учет взаимосвязей между пользователями и ресурсами; функция учета времени; а также классификация предоставляемых сервисов в Grid-системе

Многокритериальная оптимизация планирования выполнения задач в структурно-сложных системах на основе моделей репутации

In this paper we consider a problem of multi-criteria optimization of task scheduling in structural-complex systems using reputation models. We propose a new approach for integrating reputation into scheduler by applying a non-linear tradeoff scheme. Results of experiments are presented which show the effectiveness of the proposed approach.В данной работе решается задача многокритериальной оптимизации планирования выполнения задач в структурно-сложных системах на основе моделей репутации. Предложен новый подход для интеграции модели репутации в подсистему планирования с использованием нелинейной схемы компромиссов. Полученные результаты экспериментов демонстрируют эффективность разработанного подхода

A Utility-Based Reputation Model for Grid Resource Management System

In this paper we propose extensions to the existing utility-based reputation model for virtual organizations (VOs) in grids, and present a novel approach for integrating reputation into grid resource management system. The proposed extensions include: incorporation of statistical model of user behaviour (SMUB) to assess user reputation; a new approach for assigning initial reputation to a new entity in a VO; capturing alliance between consumer and resource; time decay and score functions. The addition of the SMUB model provides robustness and dynamics to the user reputation model comparing to the policy-based user reputation model in terms of adapting to user actions. We consider a problem of integrating reputation into grid scheduler as a multi-criteria optimization problem. A non-linear trade-off scheme is applied to form a composition of partial criteria to provide a single objective function. The advantage of using such a scheme is that it provides a Pareto-optimal solution partially satisfying criteria with corresponding weights. Experiments were run to evaluate performance of the model in terms of resource management using data collected within the EGEE Grid-Observatory project. Results of simulations showed that on average a 45 % gain in performance can be achieved when using a reputation-based resource scheduling algorithm

Motivating programmers through karma systems

Keeping FOSS developers motivated is a challenging problem, and their motivation levels can affect the team's productivity and satisfaction, leading to higher or lower productivity. Using reputation systems as a motivator has become the de-facto standard for many online communities, rewarding user's activity through badges of honor or achievement levels. Few open source software communities have successfully used a well-rounded reputation system to motivate developers, instead rewarding only one or a small set of activities. Very little research has been done in the area of using reputation systems to motivate people to increase their participation in open source software projects. This thesis studies Beaversource; a mix of code-hosting and social networking available to students, staff and faculty at Oregon State University, and our experiment with reputation systems as a means of motivating programmers. A survey was sent to 1,100+ Beaversource users at Oregon State University to gather demographics, and data on the use of Beaversource. One hundred users responded. Based on survey feedback, a reputation system was put in place. After the karma system was available to users, five students were interviewed to gather more information regarding their satisfaction with Beaversource and the karma system. Users reported that the reputation system worked to motivate them. Interviewees would like to see the karma system expanded with better icons and increased participation in the social networking side. Students also requested more flexibility in the karma system such as ability to affect each other's karma and give special badges to members of their project