Applicable stages: design, code, test, and deployment.
Personnel needed for the evaluation: Usability experts: 1 Software developers: 0 Users: 4	Usability issues covered: Effectiveness: Yes Efficiency: Yes Satisfaction: No
Can be conducted remotely: No	Can obtain quantitative data: Yes

 Overview

During a usability test, the tester has an expert user (in the task domain) sit next to him/her and explain the test user's behavior to the tester. This technique is used when it's not appropriate for the test user to think aloud or talk to the tester while working on the tasks.

References