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The first user is a CS researcher at MIT. The other two are undergraduates of different age and do not major in CS. We believe that this they well represents represent our user population (recall: students and researchers). Moreover, Our users are quite diverse as their academic backgrounds are different.
We also asked our users about their previous experience with annotating document. All of them have read annotated document before but have rarely annotated themselves.
Nonetheless, our users may lack the diversity in age as they are all under 25.
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