Weian Yin

Experience

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  University of Illinois Urbana-Champaign

  Sept 2019 - May 2022

  I worked as a course assistant and developer for MATH285: Differential Equations at UIUC. My responsibilities include:- Developing course materials such as Jupyter notebooks and HTML files for a differential equations course- Examining and improving lab materials for differential equations solving and interactive plotting functions by Python, answering students’ questions in bi-weekly lab sessions and proposing adjustments to course materials in weekly staff meeting based on students’ feedback- Holding weekly virtual office hours via Zoom supporting more than 500 students to solve Python programming questions and differential equations problems Show less

  • Math 285 Course Assistant

    Sept 2021 - May 2022

  • Undergraduate Research Assistant

    Jun 2021 - Dec 2021

  • Mathematics/ CS Tutor

    Sept 2019 - Aug 2021
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  Illinois Geometry Lab

  Jan 2020 - Jun 2020

  Undergraduate Research Assistant

  -Characterized the winning conditions for the two players in a Maker-Breaker game played on an interval of N integers-Developed 2 new winning strategies for both player that improves the precision of existing bound on the number of points that the Breaker plays in each round of game

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  Illinois Geometry Lab

  Sept 2020 - Dec 2020

  Undergraduate Research Assistant

  - Built graphs for the sequential sounding of a collection of bells in the language of graph theory- Discovered and proved 3 properties of the existence of permutation patterns of 4 bells under the physical constraint of bells- Utilized sound resources of the Altgeld Chimes from the mathematics department webpage to create an Android app that plays the sound of 4 bells based on user’s choice using Android Studio and Java

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  KPMG China

  Jun 2021 - Aug 2021

  Data Analyst Intern

  I interned at KPMG as a data analyst during 2021 summer. The project I worked on was developing a risk management platform for an e-commerce company. My daily tasks include:- Cleaning and analyzing two years of sales data with 2 million+ observations from a client e-commerce company to check data credibility, integrity and characteristics using t-test, z-test and Python packages- Computing and visualizing monthly, quarterly, and annual profit for 1k+ companies through pivot tables and line plots, discovered that more than 80% of company’s profit rates increased during the pandemic, which provided insights for determining major risk factors in building a risk management platform- Building regression and boosting models to predict store annual revenue by Scikit-learn, performed feature selection through collinearity checking and L1 regularization, obtained an R^2 of 80%+- Proposing potential directions for data collection based on model result, improved data retrieval and preprocessing time Show less

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  Bill & Melinda Gates Foundation

  Sept 2022 - Dec 2022

  Graduate Student Researcher

  I'm researching on implementing rubella vaccination in Nigeria.

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  EBay

  Jun 2023 - Sept 2023

  Data Scientist Intern

  I'm interning as a data scientist under the applied research team at eBay. My project focuses on improving user segmentation.• Enhanced a community detection model for user segmentation with Siamese Network and User-to-User graph, created more detailed user segmentation with stable performance• Implemented a User-to-User graph using Python and PySpark, leveraging 90 days of recent user activity in a retail category with 100 million+ observations, capturing 65.7% more user connections than the pre-existing graph• Resolved a data retrieval issue in PySpark revolved pipeline in a large code base, generated 1000% more data• Optimized hyperparameters of the Siamese Network implemented with PyTorch which improved model training efficiency,applied clustering algorithms to the user embeddings and obtained 40% higher silhouette scores for user clusters• Developed automatic naming pipeline for user clusters using generative AI based on Chain of Thought Prompting, analyzed model results in a retail category, providing insights for model development in other categories that will be put in production Show less

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  TikTok

  Jul 2024 - now

  Data Scientist