王慧玉

隨著資訊時代的來臨，電腦資訊檢索系統之重要性與日俱增，而良好系統之設計與評估實有賴對讀者相關判斷行為之研究。在影響相關判斷的眾多因素中，文獻展現次序這項變數是系統所易於控制的，且許多研究發現，訊息呈現次序的不同可能導致受試者判斷結果產生改變，因此對文獻展現次序進行深入探討實有其必要性。有鑑於此，本文首先對文獻展現次序所造成之「次序效應」進行文獻分析，並以本土化之實證研究驗證次序效應中之「賭注效應」，同時以多種筆數之文獻組設計觀察文獻筆數對次序效應產生之影響，以期對資訊檢索系統之設計有些許助益。

Among the numerous variables which influence relevance judgment, document presentation order has been attested to be actually influential by many studies. Since this variable is easy to be controlled by automated information retrieval system, it deserves our more attention and discussion. There are three points in this article: (1) to review the literature on "order effects", which is induced by document presentation order; (2) to verify the hypothesis of "hedging effect", which is one kind of order effect, by a two-stage experiment; and (3) to identify the relationship between number of document and hedging effect.

隨著外在服務環境的變遷以及內部專業人力及經費之不足，大學圖書館為支援教學與研究所提供之參考服務在品質上逐漸遭受質疑，引發了學界及業界對資訊時代參考服務之重新省思。有鑑於此，本文首先對傳統參考服務之特色及優缺點加以探討，並介紹學者所提倡之「分化式參考服務模式」（Differentiated Reference Service Model），就其產生之背景、觀念之演進、服務之特色、及實施之優缺點詳加論述，並由美國幾所大學圖書館實施之現況分析其實際應用之可行性。結論指出，分化式參考服務模式對參考服務品質之提升確有助益，相當具有可行性，可作為資訊時代大學圖書館參考服務組織重整時之參考。

Three trends have pushed university libraries to modify the structure of reference service in recent years, which are budgetary stringency, reductions in staffing, and the change of reference environment. University libraries cannot but change the reference model in order to satisfy readers’ needs in information age. This article explores the problems of traditional reference service, introduces the differentiated reference model, including its background, progress, characteristics, advantages and disadvantages, and analyzes the feasibility of the model by the experience of several university libraries in the United States.