Browsing by Author "Husu, Tuomas"

System administration is a traditional and demanding profession in information technology that has gained little attention from human-computer interaction (HCI) research. System administrators operate in a highly complex environment to keep business applications running and data available and safe. In order to understand the essence of system administrators' skill, this thesis reports individual differences in 20 professional system administrators’ task performance, task solutions, verbal reports, and learning histories. A set of representative tasks were designed to measure individual differences, and structured interviews were used to collect retrospective information about system administrators’ skill acquisition and level of deliberate practice. Based on the measured performance, the participants were divided into three performance groups. A group of five system administrators stood out from the 20 participants. They completed more tasks successfully, they were faster, they predicted their success more accurately, and they expressed more confidence during performance and anticipation. Although they had extensive professional experience, the study found no relationship between duration of experience and level of expertise. The results are aligned with expert-performance research from other domains — the highest levels of performance in system administration are attained as a result of a systematic practice. This involves an investment of effort and makes the activity less enjoyable than competing activities. When studying the learning histories, the quantity and quality of the programming experience and other high-effort computer-related problem-solving activities were found to be the main differentiating factors between the 'expert' and less-accomplished participants.