A review of quality evaluation of digital libraries based on users ' perceptions <s> Heradio et al. 273 <s> This study is to develop and evaluate methods and instruments for assessing the usability of digital libraries. It discusses the dimensions of usability, what methods have been applied in evaluating usability of digital libraries, their applicability, and criteria. It is found in the study that there exists an interlocking relationship among effective ness, effi ciency, and satisfaction. It provides operational cri teria for effectiveness, effi ciency, satisfaction, and learn ability. It discovers users’ criteria on ”ease of use,” ”or gani za tion of in formation,” ”terminology and labeling,” ”visual attractiveness,” and ”mistake recovery.” Common causes of ”user lostness” were found. ”Click cost” was examined. <s> BIB001 </s> A review of quality evaluation of digital libraries based on users ' perceptions <s> Heradio et al. 273 <s> This paper reviews how usability has been defined in the context of the digital library, what methods have been applied and their applicability, and proposes an evaluation model and a suite of instruments for evaluating usability for academic digital libraries. The model examines effectiveness, efficiency, satisfaction, and learnability. It is found that there exists an interlocking relationship among effectiveness, efficiency, and satisfaction. It also examines how learnability interacts with these three attributes. <s> BIB002
5. Error prevention. Even better than good error messages is a careful design that prevents a problem from occurring in the first place. 6. Recognition rather than recall. The user should not have to remember information from one part of the dialogue to another. Instructions for use of the system should be visible or easily retrievable whenever appropriate. 7. Flexibility and efficiency of use. Accelerators -unseen by the novice user -may often speed up the interaction for the expert user so that the system can cater to both inexperienced and experienced users. 8. Aesthetic and minimalist design. Dialogues should not contain information that is irrelevant or rarely needed. Every extra unit of information in a dialogue competes with the relevant units of information, and diminishes their relative visibility. 9. Help users recognize, diagnose, and recover from errors. Error messages should be expressed in plain language (no codes), indicate the problem precisely, and constructively suggest a solution. 10. Help and documentation. Even though it is better if the system can be used without documentation, it may be necessary to provide help and documentation. Any such information should be easy to search, be focused on the user's task, list concrete steps to be carried out, and not be too large. Jeng BIB001 BIB002  proposes an evaluation model that applies the usability definition of ISO 9241-11  . It examines the following criteria: 1. Effectiveness. It evaluates whether the system can provide information and functionality effectively. 2. Efficiency. It evaluates whether the system can be used to retrieve information efficiently.