Interactive MT systems require user guidance at points when the system reaches an impasse during processing. The user's assistance (whether in the form of menu choices, parameter entry) constitutes a form of editing that can be called "inline editing" or "in-editing" (The Pangloss Mark III MT System).
Metric: Steps for translation -- Method: Count number of times system requires assistance when translating a test corpus. -- Measurement: Number of steps needed or number of steps as percentage of test corpus size.
Metric: Time for interactive translation -- Method: Measure the amount of time it takes to perform interactive translation on test corpus -- Measurement: Amount of time for interactive translation on test corpus.
This quality will not be appropriate for certain classes of MT process, such as embedded MT.