Well, if you don’t know, yesterday the Nobel Prize for Economics this year was awarded to Professor David Card from University of California, Berkeley, for his empirical contributions to labor economics. The prize was shared by Guido Angrist and Joshua Imbens, for their contributions to the analysis of causal relationships.
Professor Card wrote a recommendation letter for me in 2020. I really appreciate him doing that. When I heard he got the Nobel Prize, I felt happy for him. I sent an email to congratulate him. I was thinking that he must be bombarded with emails and calls at the time, and so probably wouldn’t be able to read my email. To my surprise, he replied in a short time, said he was glad to know his class is still useful to me in computer science.
I got to know Prof. Card in the spring semester of 2019, when I took his course Econ-142 Econometrics and Statistical Learning at Berkeley. I barely got enrolled in the class because it was very popular at the beginning of the semester. People were already saying he was gonna win the Nobel Prize at the time, though he ended up missing it that year. The class was more than full. Many students were sitting on the ground.
But only after two weeks, enrollment dropped sharply to just about 60%, because many people found it too difficult and they quitted. I was also seriously discouraged the first time I went to the lecture. The slides were full of complicated matrix-calculation. I thus planned to quit as well. Somehow, God has his plan. Another course I was on the waitlist of turned out to be unavailable at the end, which left me no choice but to take David’s course, for I had to get enough credits. This forced me to grind so hard to figure out what the heck was in the first few lectures. I didn’t put much effort into it earlier because I thought I was gonna drop it anyway.
Well, after spending hella time reading books and picking up the linear algebra stuff that I barely remembered, I gradually came to get the gist of it. Things are always like this: Once you’ve done it, you can do it thereafter. It somewhat surprised me how fast I changed from a student being stunned by the math to become someone who represented the highest math skill level in the class. For students who are considering taking Econ-142, I’d say, the first few weeks are going to be tough, but once you’ve made it there, it’s all plain ground up ahead.
So, unsurprisingly, I went on doing pretty well in the midterm exam, got the highest score in the class. After the midterm, David said to the class that our grades weren’t quite good except two students who were way above the others. I told my friend Cecil, who sat right next to me, that I was sure the two guys he referred to were us. I knew Cecil is smart. I proved to be right after marks were released. Then I went to see Prof. Card for the first time in his office hours, sort of wanting to show off and let him know me personally.
David is very chill. I started to visit his office frequently. Looking back from today, some questions I asked him were very basic, but he was always so kind and patient to answer me. I guess that’s one of the reasons why he is well respected.
I got an A+ for this course. That’s the only A+ I had at Berkeley. I could’ve had another one from STAT-150 Stochastic Processes, but I forgot to turn in homework too many times, gee. I asked Professor Card for a recommendation letter. He agreed and we had a short talk. I was a little worried when he asked me about my GPA in China. But here is what happened, when I was saying “I don’t have good GPA in China because the courses are”, he interrupted and said, “Because they are all stupid stuff?”
Yes, Sir! That’s what I’m talking about. It feels so good to have someone who understands you, especially if he is a Nobel-Prize winner.
Time flies. It’s been two years now since I left America. I miss those days. Lake Tahoe, San Francisco, Evans Hall, friends and professors. Time really flies. Professor Card, I don’t know if I’ll see you again. But if you were to read this post, I’d like to let you know: Thank you. Your class is awesome. You are the coolest professor I’ve ever known!