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61.
Joshua Gorner Jie Zhang Robin Cohen 《Electronic Commerce Research and Applications》2013,12(2):112-123
This paper explores potential improvements to the trust modeling of agents in multi-agent systems when a social network of advisors is employed as part of the trust modeling, and in particular, examines means of optimizing the number of advisors that should be maintained in the social network. We propose three such improvements, two directly relating to the limit of advisor network size by either setting a maximum size for a buyer’s advisor network or setting a minimum trustworthiness threshold for agents to be accepted into that advisor network, and a third which uses an advisor referral system in combination with one of the first two network-limiting techniques. We provide experimental results in defence of our approach for two distinct trust modeling systems, and show how these optimizations can improve, sometimes significantly, the accuracy of different trust models (in the context of electronic marketplaces). We believe that the proposed techniques will be very useful for trust researchers seeking to improve the accuracy of their own trust models by setting the size and composition of advisor networks. 相似文献
62.
In this paper, we describe an implementation of use in demonstrating the effectiveness of architectures for real-time multi-agent
systems. The implementation provides a simulation of a simplified RoboCup Search and Rescue environment, with unexpected events,
and includes a simulator for both a real-time operating system and a CPU. We present experimental evidence to demonstrate
the benefit of the implementation in the context of a particular hybrid architecture for multi-agent systems that allows certain
agents to remain fully autonomous, while others are fully controlled by a coordinating agent. In addition, we discuss the
value of the implementation for testing any models for the construction of real-time multi-agent systems and include a comparison
to related work.
相似文献
Robin CohenEmail: |
63.
The purpose of this study was to examine individual differences in the effectiveness of learning objects in secondary school classrooms. Specifically, gender, age, grade, subject area, and computer comfort (self-efficacy) were examined in 850 students. Effectiveness was measured in terms of student attitude (learning, quality, and engagement) and student performance. No gender differences were observed between males and females with respect to student attitudes or performance. Age was significantly correlated with student attitudes and performance, however correlation coefficients were small. Grade 12 students were more positive about learning objects and performed better than grade 9 and 10 students. Science students had significantly more positive attitudes and performed better than mathematics students. Finally, students who were more comfortable about computers, appreciated learning objects more than their less confident peers, however performance was unaffected. 相似文献
64.
Numerical simulation for Fuzzy-PID controllers and helping EP reproduction with PSO hybrid algorithm
Many Fuzzy-PID controller schemes used in industry today are based on some sort of simplified fuzzy reasoning methods and PID parameters. We present a design for Fuzzy-PID controllers using a novel PSO-EP-based hybrid algorithm. We succeed in making mathematical calculations and in encouraging EP reproduction with PSO. The main advantage of our design is that the integration of the PSO-EP-based hybrid algorithm structure generates new parameters for the Fuzzy-PID control schemes. The proposed algorithm is an improved variant of PSO, a relatively recently introduced stochastic optimization strategy for Fuzzy-PID controllers that is investigated in this study. The function of Fuzzy-PID controllers is illustrated by means of a model of the induction motor control system and a higher-order numerical model. 相似文献
65.
66.
Selecting the incorrect control during the operation of underground bolting and drilling equipment causes serious injuries. Shape coding and the layout of dual control banks are two aspects of control design which require further examination. The aims of this research were: (i) to determine whether arbitrary shape coding was effective in reducing selection error rates in a virtual analogy of roof-bolting; and (ii) to determine whether any advantages exist for mirror or place layouts for dual control situations in this situation. Two experiments were conducted to address these questions. No benefits of arbitrary shape coding were evident while control location remained constant. When control location was altered, shape coding did provide a significant reduction in selection error rate. No differences between mirror or place arrangements were detected and this question remains open. 相似文献
67.
Nurcin Celik Seungho Lee Esfandyar Mazhari Young-Jun Son Robin Lemaire Keith G. Provan 《Simulation Modelling Practice and Theory》2011,19(10):2169-2188
The development of alliance-based software requires the collaboration of many stakeholders. These different stakeholders across multiple organizations form a complex social network. The goal of this paper is to develop a novel modeling framework, which will help task managers devise optimal workforce assignments considering both short-term and long-term aspects of the software development process. The proposed framework is composed of an assignment module and a prediction module. For a given task, the assignment module first selects a candidate workforce mix. Based on the candidate workforce mix, the prediction module then predicts the short-term performance (productivity) as well as the long-term performance (workforce training and robustness of the organization) of the organization. Then, the assignment module selects another candidate mix, and this iteration continues until an optimal workforce mix is found. The prediction module and the assignment module are based on an agent-based simulation method and a multi-objective optimization model, respectively. The proposed modeling framework is illustrated with a software enhancement request process in Kuali, an alliance-based open source software development project involving 12 organizations. The constructed framework is executed with varying parameters to demonstrate its use and benefit in the software enhancement process. 相似文献
68.
Yiling Chen Stanko Dimitrov Rahul Sami Daniel M. Reeves David M. Pennock Robin D. Hanson Lance Fortnow Rica Gonen 《Algorithmica》2010,58(4):930-969
We study the equilibrium behavior of informed traders interacting with market scoring rule (MSR) market makers. One attractive feature of MSR is that it is myopically incentive compatible: it is optimal for traders to report their true beliefs about the likelihood of an event outcome provided that they ignore
the impact of their reports on the profit they might garner from future trades. In this paper, we analyze non-myopic strategies
and examine what information structures lead to truthful betting by traders. Specifically, we analyze the behavior of risk-neutral
traders with incomplete information playing in a dynamic game. We consider finite-stage and infinite-stage game models. For
each model, we study the logarithmic market scoring rule (LMSR) with two different information structures: conditionally independent
signals and (unconditionally) independent signals. In the finite-stage model, when signals of traders are independent conditional
on the state of the world, truthful betting is a Perfect Bayesian Equilibrium (PBE). Moreover, it is the unique Weak Perfect
Bayesian Equilibrium (WPBE) of the game. In contrast, when signals of traders are unconditionally independent, truthful betting
is not a WPBE. In the infinite-stage model with unconditionally independent signals, there does not exist an equilibrium in which
all information is revealed in a finite amount of time. We propose a simple discounted market scoring rule that reduces the
opportunity for bluffing strategies. We show that in any WPBE for the infinite-stage market with discounting, the market price
converges to the fully-revealing price, and the rate of convergence can be bounded in terms of the discounting parameter.
When signals are conditionally independent, truthful betting is the unique WPBE for the infinite-stage market with and without
discounting. 相似文献
69.
The negative impact of online gaming on adolescents has received much attention. The question of how to reduce their pathological use of online gaming is a critical issue. Based on the concept of external justification in dissonance theory, this experimental study aimed to examine whether severity of threat and justification of effort would impact adolescent players’ attitude change toward online gaming and their subjective estimations of online gaming addiction. The results echoed predictions from classic studies in dissonance theory. When participants engaged in attitude–discrepant behavior, i.e., persuading other adolescents that an apparently interesting online game is not fun at all, their attitudes toward online gaming shifted more dramatically to the negative side in the context of a low level of threat rather than a high level of threat. Additionally, the magnitude of attitude change was more prominent when participants exerted more rather than less effort to engage in attitude–discrepant behavior. Moreover, a similar pattern of participants’ evaluations of the likelihood of online gaming addiction was also observed. The findings show that dissonance theory has the potential to be useful for inducing adolescent players to disengage in online gaming. 相似文献
70.
Heather E. Golden Christopher D. Knightes Ellen J. Cooter Robin L. Dennis Robert C. Gilliam Kristen M. Foley 《Environmental Modelling & Software》2010,25(12):1722-1737
Directly linking air quality and watershed models could provide an effective method for estimating spatially-explicit inputs of atmospheric contaminants to watershed biogeochemical models. However, to adequately link air and watershed models for wet deposition estimates, each model’s temporal and spatial representation of precipitation needs to be consistent. We explore how precipitation implemented within the Community Multi-Scale Air Quality Model (CMAQ) model algorithms, and multiple spatially-explicit precipitation datasets that could be used to improve the CMAQ model deposition estimates, links with the standard precipitation sources used to calibrate watershed models (i.e., rain gage data) via modeled water fluxes. Simulations are run using a grid-based watershed mercury model (GBMM) in two watersheds. Modeled monthly runoff suggests that multiple resolution Parameter-elevations Regressions on Independent Slopes Model (PRISM) and National Multi-sensor Precipitation Analysis Stage IV (NPA) data generate similar monthly runoff estimates, with comparable or greater accuracy when evaluated against stream gage data than that produced by the base rain gage data. However, across longer time periods, simulated water balances using 36 km Pennsylvania State University/National Center for Atmospheric Research mesoscale model (MM5) data are similar to that of base data. The investigation also examines the implications our results, providing suggestions for linking air quality and watershed fate and transport models. 相似文献