Internship in Beijing as A Quant in 2025 Summer
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I applied for countless internships in Shanghai, but somehow, I ended up in Beijing. I still remember the excitement when I received the internship offer in early July. I thought I was blazing a new trail, so I came here, rented an apartment, and started my internship life.
Living in Beijing really boosts your happiness—as long as you’ve lived there, your happiness in any other city goes up significantly. Haidian District is noisy, fast-paced, has unstable weather, feels old, and the food isn’t great. The happiness index here is far below Zhuhai’s. In this place, you have to find your own joy.
Fortunately, we got xvxv here. We watched beautiful sunsets, strolled through supermarkets, drank Douzhi, grew flowers, made rings, walked in Ditan Park, and ate until we were in a carb coma. We went into the woods to find the ugliest ducks, played Hearthstone and the Paramecium game, visited an AGI bar to check out the startup vibe, won a small watermelon at a ring toss, and explored coffee shops. We also went to Universal Studios, a theme park we had been longing to visit.
Many moments made me feel loved; that is where a lot of the happiness in life comes from.
During this time, I also met up with some friends who are also in Beijing. It feels like everyone has their own ideas, and exchanging thoughts is a really fun thing to do.
The Quant internship experience was fantastic overall, especially for students who like to face challenges. I worked on optimization algorithms for multi-factor strategies, sticking with the same project from onboarding until now. I learned something new every day and implemented it. Over this small cycle, my math and coding skills improved a lot. Moreover, I mastered many quantitative research methodologies, improving my reaction speed, sensitivity, and gaining some philosophical insights into things.
It felt more like doing research here because I was reading papers every day and running experiments on backtest data. It was mostly portfolio optimization: starting with feature engineering, then researching covariance estimation, volatility modeling, robust optimizers, and so on. Every time I finished reading, I’d hack away at the code. When I finally managed to get some decent-looking data, my mentor would pull me in to do ablation studies and further optimization. He taught me that building models requires a high level of market intuition and to be cautious with things that have weak interpretability. My mentor is top-notch. Even though he would laugh crazily whenever he saw me get an error, he taught me how to think about a strategy, how to find ways to improve, how to dig for patterns in data, how to get to the bottom of things, and how to perceive market changes and react quickly. Doing quantitative research requires deep accumulation, continuous thinking, and keen perception. My colleagues around me are outstanding in these areas.
The atmosphere here is excellent. One moment we’re joking at lunch about entering the stock market to manually hedge, the next we’re laughing at our desks about drinking Mixue Bingcheng. Before I went home, they discussed the industry status with me, talked about future plans and directions, and helped me edit my resume and expand my network. There is none of that “finance bro” vibe that people often criticize. In the weekly meetings, everyone listens seriously to every speaker regarding their weekly thoughts and results, offering practical, detailed advice, and showing the logic behind how they view problems.
The internship felt very fast-paced to me, whereas academic research isn’t usually this fast. The internship was happy, but deep down, I feel that “slow thinking” suits me better. So, I have been thinking about my future direction and what I am truly passionate about. There were too many things going on during this time, so time for self-doubt was limited; as soon as a bad thought popped up, I just ran off to work.
From my freshman year until now, I’ve heard many seemingly friendly discouraging views—saying “you cant do this”. People unconsciously use preset frames to constrain others, but I have always believed that I would be an outlier; perhaps everyone is an outlier in some aspect.
I have slowly realized my own trait: I won’t give up the things I want to fight for just because of other people’s views, nor will I settle in a spiritual sense. Even if sometimes I know the established route would bring a lot of benefits, I will still do my own thing. This is a form of respect for myself.
I am tracking developments in my research field, reading papers, taking notes, writing code, reproducing articles, summarizing regularly, and forcing myself to come up with new ideas. After a day of interning, I’d go back, open a paper, and feel groggy and sleepy. I found myself immersed in this mix of pain and happiness, often feeling a loss of control over life. It comes from my own arrogance and self-expectations. I always hope to create a bigger impact—but at the same time, these things act like a sword at my back, pushing me forward. After a while, I suddenly started to enjoy this lack of control. I’d think, “Hey! Let’s see how bad things can get!” and then immediately schedule a meeting with a senior or professor for the near future, forcing myself to work. These recurring emotions filled my summer.
Time flies. I haven’t been home this holiday, so I need to hurry back and pack. This summer was exhausting yet happy. I have almost forgotten what school days are like, but regardless, I am finally returning to our beautiful campus.