West High Student Named One of the Nation’s Top 300 Student Scientists


Daphne Liu

Anika Rao

In January of this year, the Society for Science announced that Daphne Liu was among the top 300 scholars in the Regeneron Science Talent Search 2021, the most prestigious science and math competition for high school seniors in the nation. She and the other scholars were selected from 1,760 applications received from 611 high schools. Daphne, a senior at West, will receive $2,000 for her achievements and West will receive $2,000 to further its STEM program. 


Her project was titled: Using Machine Learning to Predict Physiological Metrics from PPG Pulse Shapes.


I had the opportunity to talk to Daphne about her project and experience in the Regeneron Science Talent Search, her experience at West High and as a woman in the STEM field, and her plans for the future. 




Anika: Tell me a little about yourself. 


Daphne: My name is Daphne and I’m a senior at West right now. I have been going to West since eighth grade, so I was an ELPer for one year. I am very interested in computer science and research, but I’m also a part of the tennis team and debate team.


Anika: Tell me about the Regeneron Science Talent Search Competition (STS). What is it, and how were you introduced to it? 


Daphne: The Regeneron Science Talent Search Competition is considered “the most prestigious science and math competition for high school seniors.” There’s this pretty rigorous application process you have to go through: you have to submit a research paper, answer some short questions and some essay questions about the research, and get recommendation letters  from a teacher and your research mentor. 


Since I do science fair and run the Science Fair Club at West, I knew about this competition. It’s run by Society for Science, the same organization that runs the International Science and Engineering Fair (ISEF). 


I also participated in a research camp at MIT over the summer called RSI, which really advocates for its participants to submit to STS. So since most of my peers were doing it, I decided to as well.


Anika: What was your project titled and what was your process for developing it?

Daphne: My project was titled Using Machine Learning to Predict Physiological Metrics from PPG Pulse Shapes. 


PPG or photoplethysmography is a measurement about your pulse and is really rich in physiological information.


My research mentor is the CTO of a company called Whoop, and they have these wearable straps that you can wear on your wrist which collects the PPG measurement.


And so what I did is I used machine learning to identify the shape of that pulse and use it to predict someone’s age. If the prediction of the age is really different from the person’s actual age, it suggests that the person’s cardiovascular or physiological health is off – so they may be unusually healthy or unusually unhealthy. That makes it a good indicator of whether they need to see a doctor.


My mentor has access to a huge database. Whoop collects the PPG measurement in increments of ten seconds, and you can parse through that data and extract the features in it – so if there’s a peak in one spot you can measure that, or you can measure the slope. Then you can take all of those features and use them to train a machine learning algorithm which spits out a prediction.


It’s really helpful because it’s outside of a clinical setting. All you have to do is put on a wearable strap, and you can learn about your physiological health in real time.


Anika: What was the most interesting thing you learned throughout the process?


Daphne: This process definitely changed my perspective on wearable technology because I previously thought it was something only super active athletes used, but throughout the process, I realized that it isn’t just for training athletes. In this technological age, it could really contribute to health advancements. The applications of wearable technology are really broad, and that really interests me.


Anika: What did winning this award mean to you?


Daphne: Obviously winning this award makes me very proud. But my biggest takeaway is that I was really glad that people noticed that my research has real world impacts. That feeling is really great because I feel like I’m actually doing something that could potentially change the world.


Also, after announcing the awards, the organization put together a meet and greet for the awardees. I found a community of students who all have the same interests as me and are all doing their own part in conducting research that could also possibly change the world. It really humbles me to be in their presence and reminds me that our generation is pretty great.


Anika: Who has been an important mentor for you?


My research mentors have definitely been huge in this process –  if I didn’t have them, I would probably not have received any recognition for my project. 

And some of the teachers at West have also been super important mentors to me, especially Mr. Vawdrey and Enrique Arce-Laretta.


Mr. Vawdrey has always been so supportive and I gained a lot of the skills I needed to actually tackle a machine learning project in his computer science classes. He’s always been super willing to help me and solve problems.


And Enrique has literally been there with me for every one of my biggest milestones. He’s worked with people who are involved with Science Fair and STS, so he knows a lot about it and has a lot of wisdom to share, and he’s also been super willing to help whenever I’ve needed it. 


Those two teachers have been life changing


Anika: How were you introduced to the STEM field?


Daphne: I honestly feel like my story is pretty lame. I wish I had a better story to tell, but I feel like I almost inherited an interest in STEM. My parents are both in STEM and my brother was super STEM-oriented and that definitely influenced me.


But when I was 9, so in 2013, my brother actually went to the International Science and Engineering Fair, and I was able to visit him while he was there. I remember so clearly walking through the aisles of this huge convention center, and I just fell in love with it. That’s why I decided to pursue research on my own.


Anika: What is it like being a woman in STEM? Do you think diversity in STEM is important and if so, how do you think we can encourage it?


Daphne: Being a woman in STEM is super empowering. At first, I definitely had doubts and I felt really insecure, but as I’ve matured and learned more, I’ve realized that it’s super important to push for diversity. Part of the reason I was so scared at my first class was that I was unwilling to talk and collaborate, and it was very difficult for me because I didn’t want to look like I was failing or struggling.


I always say that innovations cannot just be created by a narrow slice of humanity because that will never reflect the diverse world that we live in, and clubs like Girls Who Code and SheTech at West have been super helpful for me in bringing female representation into STEM. When you have peers who you can relate to and who are going through the same struggles as you, it’s much easier to get through them together. 


I definitely think that’s the first step in diversifying our workforce. And by diversifying our workforce, we are making technology and innovations much more accessible to everyone. 


I actually wrote my IB extended essay about this, because the problem is that many of the ways STEM is taught are not suitable for girls because our minds are completely different than our male counterparts, and so I definitely think that diversity in STEM is very important. 


Anika: You talked about teaching STEM differently. Could you elaborate on that a litte?


Daphne: That’s definitely one thing I would change about our education system as it relates to STEM. I don’t think STEM as a subject needs to be changed at all – it’s obviously changing the world – but I do think that a lot of people from the very beginning really despise STEM. I think part of that is because of the way that it’s taught, because it seems very daunting and intimidating. But in reality, STEM isn’t as bad as you would think. It’s the way that it’s taught that’s really pushing people away, especially girls and people of color.


Anika: What advice would you share with other students who are considering pursuing a career in the STEM field? 


Daphne: This is going to sound super cliche, but you’re going to encounter setbacks and they’re super frustrating, but there’s no way that you won’t get through them. Also, a lot of the time, to get over those setbacks and overcome those challenges, you have to find people that can work with you and who have the same interests as you. When you find your group of people, they’re going to be willing to help, and it’s a lot more comforting to know that there are people like you out there who will always support you. 


Anika: What have been your biggest setbacks or challenges throughout this process?


Daphne: There are two different types of challenges I faced:


The first is imposter syndrome. When you’re working with super accomplished researchers or you’re at a camp with a bunch of people that are incredibly intelligent, you find yourself wondering why you’re there or whether you’re qualified to actually conduct research, and you have a lot of self doubt. But over time, you realize that you put other people on a pedestal so you see all the good things about them, but when they look at you, they only see the good things about you. It’s all about finding a good balance. 


The second setback is a feeling of constant imperfection.


When I was first presenting my research in front of professionals, I would get super scared for the questions that they would ask because when they’re interrogating you, you feel like “Oh was my research wrong or really bad?” In reality, that’s all part of the process of making sure that your research is thorough. So when they ask questions, I realized they’re not trying to knock my research down, they’re just interested and want to make sure they understand it correctly. And throughout that process, it improves your research. 


Anika: What advice would you share with people in general based on your academic success?


Daphne: Anything can happen. When I was 14 and a freshman, there’s no way that I would have thought that I could do even half the things I’ve accomplished at this point, so make sure to have faith in yourself and remember that you’re not alone.




Daphne plans on going to college, possibly getting a PhD in computer science, and continuing to do research. She has been accepted to Harvard University and is considering enrolling there in the 2021 Fall Semester. Along the way, she wants to continue to push for female representation and, in turn, create a more diverse generation of scientists, technologists, and leaders.