The effects of task complexity and time availability limitations on human performance in database query tasks

Prior research on human ability to write database queries has concentrated on the characteristics of query interfaces and the complexity of the query tasks. This paper reports the results of a laboratory experiment that investigated the relationship between task complexity and time availability, a characteristic of the task context not investigated in earlier database research, while controlling the query interface, data model, technology, and training. Contrary to expectations, when performance measures were adjusted by the time used to perform the task, time availability did not have any effects on task performance while task complexity had a strong influence on performance at all time availability levels. Finally, task complexity was found to be the main determinant of user confidence. The implications of these results for future research and practice are discussed. (c) 2004 Elsevier Ltd. All rights reserved.