The Intricacies of User Adjustments of Alerting Thresholds.

OBJECTIVE: We address the question of necessary conditions for users to adjust system settings, such as alarm thresholds, correctly.

BACKGROUND: When designing systems, we need to decide which system functions users should control. Giving control to users empowers them, but users must have the relevant information and the ability to adjust settings correctly for their control to be beneficial.

METHOD: Using the example of adjusting an alerting threshold, we analyze the conditions for when users can and when they cannot possibly adjust threshold settings adequately.

RESULTS: We identify two obstacles that limit users' ability to adjust thresholds adequately: (a) the difficulty of determining the correct threshold settings, especially because of users' strong response to false positive indications, and (b) the difficulty of collecting the information necessary for setting the threshold.

CONCLUSION: Users often cannot identify the optimal settings for a system, so it is unlikely that they choose adequate system settings.

APPLICATION: System designers must consider the difficulties users face and analyze them explicitly when deciding on user involvement in processes.