Empirical study on end-users' update performance for different abstraction levels

Abstract

Recent laboratory experiments have shown a strong tendency that database users can perform better at the conceptual level than at the logical level. The experiments measured users' performance for the tasks of database design and database retrieval. Besides database design and retrieval, the third major database task is update. User performance for updates has not been measured. With the widespread availability of databases, updates will be done frequently by end-users. This task is gaining in importance as a measure of the usability of a database system. An experiment was conducted to measure the effect of different abstraction levels on user performance for updates. A conceptual level group used the entity relationship model with an entity relationship query language KQL, while a logical level group used the relational model with the standard relational language SQL. Performance was primarily measured by the accuracy of the update query. Secondary measures of time and confidence were also taken. The results showed that updates at the conceptual level were 15.4% more accurate and required only 57.8% of the time taken for logical level updates. The differences were statistically significant with p values of less than 0.03.