在開發多代理人線上拍賣系統時,必須經由效能評估來確認系統模式的效率是否良好,本論文主要在探討代理人溝通模式與競標策略是否為影響系統效能的有效因子。不同的線上拍賣系統經常使用不同的拍賣機制,而各種拍賣機制決定得標者的方法也不相同。許多學者因應不同的拍賣機制發展出不同的競標策略,而這些競標策略所需的資訊也不盡相同。在複雜與變動的網路環境當中,行動代理人必須移動至拍賣網站,與其他代理人及所處環境進行溝通以完成競標的任務。本論文將拍賣的過程分為查詢與競標兩部分,在查詢過程中代理人會根據使用者的要求至各個伺服器中蒐集資料,在競標過程中代理人自主的進行競標。本論文將溝通模式與競標策略作為二因子實驗計畫中的自變數,溝通模式區分為直接協調與物件協調兩種溝通模式,競標策略則包括九種不同的競標策略。本論文藉由建構簡易拍賣系統並模擬拍賣的過程,量測系統反應時間與傳輸流量,透過ANOVA分析及運用主因子效應圖找出較佳的系統模式。根據分析得知在查詢流程部分與競標流程部分,反應時間受到代理人溝通模式的影響,傳輸流量受到競標策略與代理人溝通模式的影響。根據主因子效應圖可得知在查詢流程與競標流程部分,直接協調的反應時間較短,而物件協調的傳輸流量則較少。此結果可做為未來系統開發者的參考。
To develop an effective Internet auction system with multiple agents, the system performance should be investigated to validate the system design. In this paper, the auction task is divided into two processes one is searching process and the other is bidding process. In searching process, agents search data based on user requirements across auction servers. In bidding process, agents autonomously bid goods with other agents. A multi-agent auction system was implemented to simulate Internet auctions for collecting experimental data. Bidding strategy and coordination model were factors of the two-factor factorial experiment. Coordination model has two categories: direct coordination and Linda-like coordination. Bidding strategy includes nine different strategies. The performance measurements were system response times for inter-agent communication and data transmitting volume through the bidding process. These two measurements were defined as response variables, and the ANOVA was applied to test the significance of the factors. In searching and bidding processes, the results showed coordination model is significant to the system response time, and bidding strategy and coordination model are significant to the data transmitting volumes. From the main effect plots, the response time of systems with direct coordination model is shorter than systems with Linda-like coordination model, and data transmitting volume of systems with Linda-like coordination model is lower than systems with direct coordination model.