Dandan Zheng, Developer in Katy, United States
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Dandan Zheng

Verified Expert  in Engineering

Data Scientist and Developer

Katy, United States
Toptal Member Since
June 2, 2022

Dandan is a senior data analyst and data scientist with 5+ years of professional experience and an extensive background in predictive models, AB testing, dashboard, and end-to-end analytics projects. She has worked in the technology, live streaming, social media platform, and oil and gas energy industries, constantly collaborating with cross-functional teams. Besides work, Dandan enjoys traveling and is a big-time computer gamer.



Preferred Environment


The most amazing...

...project I've developed is Tiktok's live streaming user labels to analyze user experience, quality of streams, and potential areas of growth worldwide.

Work Experience

Data Analyst

2021 - PRESENT
ByteDance | TikTok
  • Led and developed TikTok live streaming quality user profile system based on user experience and service of quality metrics. Classified and predicted user labels for customized strategies and applied them to billions of TikTok live users worldwide.
  • Designed and created a dashboard of key metrics and trend analysis for business lines such as eCommerce and visual quality and conducted root cause analysis on key metrics changes weekly.
  • Created and conducted AB tests on live streaming quality strategies, defined AB test design and analysis guidelines, and improved user experiences and engagement worldwide.
  • Developed and maintained data pipelines for data security and data center migration and optimized data pipelines that process billions of data every day.
  • Managed the live streaming quality data analysis team, mentored junior analysts, planned the team objectives, and generated reports for senior managers in and across departments.
Technologies: SQL, Python, Data Analysis, Machine Learning, Dashboards, A/B Testing

Senior Analyst

2017 - 2020
  • Designed and developed prediction models for equipment failure. Collaborated with teams from SMEs for feature extraction and business value and implemented models in Databricks, Dataiku, and Spotfire with scheduled updates.
  • Analyzed treatment effectiveness using a time-varying survival model, clustering, and statistical tests. Calculated features, identified trends leading to cause, and communicated the financial evaluations and preventive maintenance recommendations.
  • Created and instructed the "analytics academy" courses to promote a company-wide analytics culture, acting as a pivotal contributor in leading training and awareness efforts on analytics across the company.
  • Developed daily metrics, trip simulations, and customized calculations for drilling economic analysis.
  • Designed and developed a key dashboard that measures daily performance, cost and profit, incidents, and plans for drilling, which the department uses on a daily basis.
Technologies: Data Analysis, Machine Learning, Dashboards

Segmented User to Customized Strategy

Clustered social media users into different labels based on user engagement, experience, quality of service, and geolocations using SQL and Python. Then used key indicator metrics to determine key audiences for strategy and evaluated user groups to assess growth areas in engagement.

Realtime Time Series Equipment Failure Machine Learning Prediction Model

Designed and developed a real-time machine learning prediction model to foresee if the equipment will fail soon or not. The model precision is over 85%.

The development included:
1. Data gathering
2. Data cleaning
3. Feature development
4. Model creation, training, and optimization
5. Model implementation into production
6. Usage education and maintenance.
2015 - 2017

Master's Degree in Engineering

University of Texas at Austin - Austin, Texas, USA


Microsoft Certified: Azure Data Scientist Associate



AWS Certified Machine Learning – Specialty

AWS Amazon




Data Science, Agile Project Management


SQL, Python


Databricks, Dataiku


Data Pipelines


Data Analysis, Machine Learning, Dashboards, Modeling, A/B Testing, Predictive Modeling, Unsupervised Learning, Experimental Design

Collaboration That Works

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