Thanks. Now we are going to ask you some questions about:

• The task
• Workload
• Easyness and usefulness of the system
• Enjoyment and trust

Note: When we say "the Task", we refer to the task about finding a second-hand car.





Note: When we say "the System", we refer to the Improved System (the one that you have just used).



Click next to start. We ask now some questions about the task.

For each of the statements below, please indicate the degree of your agreement with the statement by selecting the appropriate choice. I understood the task I was asked to do I felt comfortable with this task I knew enough about cars to accomplish this task It was easy to accomplish the task I am satisfied with my choice I am confident that I have found my optimal choice from the ones in the catalog I think that I have found a very good choice from the ones in the catalog



The following questions are meant to compare the use of the improved system with the baseline one.

With the improved system, it was easier to accomplish the task I am more satisfied with my choice I am more confident that I have found my optimal choice from the ones in the catalog I have found a better choice NASA has designed a standard test called NASA TLX for subjective workload assessment.



Please click on each scale at the point that best indicates your experience of the task.

Mental demand

How much mental and perceptual activity was required (e.g., thinking, deciding, calculating, remembering,

looking, searching, etc.)? Was the task easy or demanding, simple or complex, exacting or forgiving? Physical demand

How much physical activity was required (e.g., pushing, pulling, turning, controlling, activating, etc.)?

Was the task easy or demanding, slow or brisk, slack or strenuous, restful or laborious? Temporal demand

How much time pressure did you feel due to the rate or pace at which the events occurred using the system?

Was the pace slow and leisurely or rapid and frantic? Effort

How hard did you have to work (mentally and physically) to accomplish your level of performance? Performance

How successful do you think you were in accomplishing the goals of the task set by the experimenter (or yourself)?

How satisfied were you with your performance in accomplishing these goals? Frustration level

How insecure, discouraged, irritated, stressed and annoyed versus secure, gratified, content, relaxed and complacent

did you feel during the task? Tick the factor that represents the more important contribution to the workload for the task: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: Which factor represents the more important contribution: We ask now some questions about the system.

For each of the statements below, please indicate the degree of your agreement with the statement by selecting the appropriate choice. I often became confused when I used the system I made errors frequently when using the system Interacting with the system was often frustrating I found it easy to recover from errors encountered while using the system The system was rigid and inflexible to interact with I found it easy to get the system to do what I wanted it to do The system often behaved in unexpected ways I felt in control of the system I found it cumbersome to use the system My interaction with the system was easy for me to understand The system provided helpful guidance to interact with it This is a user-friendly system I can quickly find the information I need on this system The system was easy to use for product assessment The system was easy to use to compare products The system was easy to use to accomplish the task Overall, I found the system easy to use The following questions are meant to compare the use of the improved system with the baseline one.

For each of the statements below, please indicate the degree of your agreement with the statement by selecting the appropriate choice. I became more confused when I used the system I made more errors when using the system Interacting with the system was more frustrating I found it easier to recover from errors encountered while using the system The system was more rigid and inflexible to interact with I found it easier to get the system to do what I wanted it to do The system behaved more in unexpected ways I felt more in control of the system I found it more cumbersome to use the system My interaction with the system was easier for me to understand The system provided more helpful guidance to interact with it This system is more user-friendly I can more quickly find the information I need on this system The system was easier to use for product assessment The system was easier to use to compare products The system was easier to use to accomplish the task Overall, I found the system easier to use For each of the statements below, please indicate the degree of your agreement with the statement by selecting the appropriate choice. This system provided good quality information About the products, I got a good "picture/understanding" of the different possibilites for my region of interest This system was useful for product assessment This system was useful for comparing products This system was useful for accomplishing the task The following questions are meant to compare the use of the improved system with the baseline one.

For each of the statements below, please indicate the degree of your agreement with the statement by selecting the appropriate choice. This system provided better quality information About the products, I got a better "picture/understanding" of the different possibilites for my region of interest This system was more useful for product assessment This system was more useful for comparing products This system was more useful for accomplishing the task This system improved my performance in accomplishing the task This system increased my effectivenes for accomplishing the task For each of the statements below, please indicate the degree of your agreement with the statement by selecting the appropriate choice. I found my interaction with this system interesting I found my interaction with this system enjoyable The following questions are meant to compare the use of the improved system with the baseline one.

For each of the statements below, please indicate the degree of your agreement with the statement by selecting the appropriate choice. I found my interaction with this system more interesting I found my interaction with this system more enjoyable Imagining that an online vendor uses this system for his store.

For each of the statements below, please indicate the degree of your agreement with the statement by selecting the appropriate choice. I would feel that this online vendor is honest I would feel that this online vendor is trustworthy I would feel that this online vendor is competent I would feel that this online vendor cares about customers The following questions are meant to compare the use of the improved system with the baseline one.

For each of the statements below, please indicate the degree of your agreement with the statement by selecting the appropriate choice. I would feel that this online vendor is more honest I would feel that this online vendor is more trustworthy I would feel that this online vendor is more competent I would feel that this online vendor cares more about customers The questionnaire has finished.

Click "Finish" to continue.