Online patron access catalogs (PACs) were the focus of a number of sessions at the Online 82 meeting held in Atlanta at the beginning of November. More general sessions also offered food for thought for designers and administrators of such catalogs.
For instance, comments on teaching users online by Jeffrey Griffith of the Congressional Research Service included a number of guidelines for the construction of effective error messages. Experience suggests that:
- error messages should occupy no more than one screen display
- messages should be connected to, or point at other, optional, help screens
- the messages should be worded so as to absolve the user from "blame' throwing the "fault" onto the system with wording such as: "the system could not interpret the last instruction"
- messages should illustrate a correct example in words rather than by means of actual examples. When real examples are given, users frequently type these in character by character and thus do not get the results needed for their particular searches.
The effectiveness of a particular error message can be gauged by monitoring the number of times in which the same error message is invoked twice in succession. The speaker commended the error messages on Lexis/Nexis as being particularly effective.
The validity of those observations was reinforced by a presentation on one of the studies OCLC is conducting as part of the Council on Library Resources sponsored Online Public Access Catalog Study. Referred to as "transactional analysis," the project entails examination of the transaction logs from four online public access catalogs-those of Ohio State University, the Library of Congress, Dallas Public Library and Syracuse University. The logs are being analyzed in an attempt to obtain a description comprising current online catalog search patterns. With such a description, it is hoped that architects of online catalogs will be better able to predict search patterns and thereby design more "user friendly" catalog interfaces.
The transaction log data is being analyzed and charted in graphs, matrices and probability tables. Patterns being examined include the probability of a user choosing to move from one specific command to another, the number of commands per session, the frequency of occurrence of certain command sequences, etc. The work of analysis is not yet completed.
Results to date indicate that subject searching is the operation most frequently performed by the public users of PACs and that the occurrence of an error during searching is most likely to be followed by the occurrence of another error.
In another aspect of the Council on Library Resources study, Douglas Ferguson of the Research Libraries Group (RLG) reported on-a survey of 8,000 public access catalog users who were asked how services could be improved and which new services they would like to see added. Their suggestions included:
- the ability to conduct in-depth subject searches and to access files which would provide subject authority/related term information
- the ability to access the tables of contents, summaries and indexes of the items cataloged
- access to information on the circulation status of the items retrieved-an indication of whether or not the item is on the shelf available for loan
- the ability to print the results of the search
- wider availability of terminals both in the library and at other locations
- inclusion of more information in the PAC: a larger proportion of the library's holdings and access to records for all forms of material
Despite their approval of the technology, these 8,000 PAC users are experiencing a number of problems when using online catalogs. For example, broadening or narrowing the scope of a search to increase or reduce the number of citations retrieved presents difficulties for many users. Determining the correct subject term was another problem area. Truncation appears to be a concept that many users have difficulty grasping.
Other problems reported relate to the library environment in which the PAC is situated rather than to the catalog itself. A major problem is that users are unclear as to which section of a library's holdings are online; they have been told but find it difficult to remember. Signs and brochures are insufficient reminders. The other common complaint relates to an inadequate amount of writing space on the tables at the terminals, a problem can- pounded by the fact that printers are not commonly made available to support PACs.
Joe Matthews, another contractor for the CLR study, enumerated a group of factors with which PAC users have difficulty:
- the use of codes and abbreviations-in screen displays, in search formulation, and in the explanations and error messages on the systems
- the screen displays themselves- the layout of the display screens understanding multiple record displays, the wording of explanations, and the difficulty of identifying the call number in the screen display
- managing the search process- remembering the commands, expanding and reducing the set of search results, and remembering which set of a library's total holdings is included in the PAC
- subject searching-selecting appropriate subject terms, remembering the search process, increasing the size of the result set, handling truncation
- other search operations
- adjusting to delays in system responses-long lists of choices, messages which are too long, undue response times, and the problem of having to wait for a terminal to become available.
