Central measurable human factors
for user interface evaluation
 

• Speed of performance

How long does it take to carry out the benchmark tasks?
 
• Error/success rate

How many and what kind of errors do people make in carrying out the benchmark tasks? How many tasks were successfully completed?
 
• Time to learn

How long does it take for users to learn what actions are required to achieve the benchmark tasks?
 
• Retention over time

How well do users maintain their knowledge and skills over given periods of time?
 
• Subjective satisfaction

How much did users like using verious aspects of the system?