Computer Vision News - January 2021

You made a big change last year, when you started teaching at ETH. How is your scientific activity different? I have lots of observations and thoughts on this. I didn’t really have teaching experience when I was at Max Planck. When I joined the Computer Science Department, I saw how important teaching was for the department and for each professor. Most of the people spend a lot of time and energy to teach students, to design their lectures, to design their tutorials, to really help the students to learn something and develop their career. That’s a key for universities, and I agree with that. Teaching the next generation is really a key foundation of a good university. I really observe that. The second thing I learned from experience. In order to teach well, you need to spend lots of time. When you think you understand something, actually you don’t. When you teach, you really need to have a much deeper understanding of every detail, because students come back with questions. I spend lots of time preparing my lectures. I also learned a lot during this preparation. I think the students appreciate the effort. Do you ever tell your students, in class, “I don’t know” ? Yes, it happens. If I teach a lecture three or four times, there will still be questions that I don’t know the answer to, maybe because the question is linked to another subject, another research area of which I don’t really know the details. Do you ever feel bad that you don’t have the answer? No, no no… being honest is a very important part of teaching. It doesn't really bother me. I honestly tell students that I don’t really know, but we can discuss it. I really look into the answers of students’ questions. Can you give us one example? One thing we teach is about Google image search. The student asked, “What kind of technology does Google use now?” I don’t really know. What I talked about was a paper from two or three years ago. Now, I don’t really know exactly what Google is using. I have to say, “I don’t know. Maybe we can check online and see if there is a recent paper from Google.” 32 Siyu Tang “When you teach, you really need to have a much deeper understanding of every detail, because students come back with questions”