About Me
I am a PhD researcher at Drexel University using statistical and machine learning techniques to predict mental health and mortality outcomes in large datasets. Previously, I completed my undergraduate degree in Cognitive Science at the University of Pennsylvania with a concentration in Computation and Cognition where I also used machine learning and natural language processing techniques for analyzing customer feedback on medical and consumer products.
My research interests lie in the predictive ability of Biological and Brain age which can be calculated using blood-based and brain imaging data. I answer these questions using tools such as multilevel linear regression frameworks, neural nets, Bayesian network analysis, and natural language processing.
I also have experience in providing product improvements and financial forecasting for pharmaceutical and technology leaders backed by data analytics. These insights have been used by business leaders at companies like Merck, Samsung, Dexcom, and Janssen Pharmaceuticals to provide effective product and drug launch.
I am most skilled in: R and Python
Education
Drexel University
PhD in Applied Cognitive and Brain Sciences
2021 - Present
University of Pennsylvania
BA in Cognitive Science
2017 - 2021
Work Experience
Merck & Co.
Business and Data Analytics Intern
2024
As a PhD intern at Merck, I led a team of four data scientists and business analysts to develop a comprehensive data table for machine learning cluster analysis, specifically to foracast a new LDL-C drug. This project involved analyzing patient claims, financial, and biomarker data from 99 million patients using Spark SQL, R, and Python. I presented our analytics to the internal VP, where I recommended targeted marketing strategies for the drug’s upcoming launch in both the US and global markets. Additionally, I collaborated with consultants from Accenture and McKinsey & Company to present our fincial forecasts to top stakeholders.
Delve Inc.
Data Science Intern
2020
At Delve Inc., a product design consulting firm specializing in medical and consumer products, I analyzed consumer trends using machine learning models for Samsung America for their Flip and Fold phones. This analysis was based on large-scale customer surveys, utilizing text-scraping and sentiment analysis techniques in Python. Additionally, I designed and implemented a Natural Language Processing Customer Review Analyzer for Dexcom’s G7 continuous glucose monitor, using tools like BeautifulSoup and Docker, to investigate the underlying reasons for customer satisfaction and dissatisfaction.
Selected Projects and Research
Using Biological Age in Children with Perinatally-Acquired HIV to Predict Mental and Physical Health Outcomes
github.com/Aychsi/PHACS-AMP.gitData from the Pediatric HIV/AIDS Cohort Study (PHACS)
Designed a new advanced statistical framework to forecast mental health and mortality risks for children with PHIV over time in a large electronic health records (Pediatric HIV/AIDS Cohort Study). Briefly, this new algorithm incorporates the starting health condition of each child to inform future health outcomes. This method has been shown to outperform previous methods of predicting health outcomes using Biological Age.
Biological age and brain age in midlife - relationship to multimorbidity and mental health
www.sciencedirect.com/science/article/abs/pii/S0197458023002117Data from the Midlife in the US (MIDUS) Study
Developed a statistical model to incorporate both blood-based and grey matter volume to calculate both Biological and Brain Age which is used to predict multimorbidity. This is the first paper to examine both biological and brain age as a predictor for multimorbidity.
Natural Language Processing and Binge Eating Prediction for Smartwatch Software
https://github.com/Aychsi/NLP_BingeEatingModus Create LLC is a consulting and product development firm
I worked as a consultant with the Center for Weight, Eating and Lifestyle Science (WELL) Center at Drexel and Modus Create LLC as a PhD consultant to develop a binge-eating prediction application for smartwatches. I suggested and implemented a personalized Natural Language Processing to detect which foods are more likely to cause binge-eating episodes. I also used XGBoost to achieve above an 80% sensitivity rate to predict binge-eating episodes based on time of day, the number of calories in the food, and past episodes.
Delve Inc. (formerly Bresslergroup Inc.) is a product innovation firm specializing in consumer and medical devices
Various projects as a Data Science Intern at Delve Inc. This includes providing data visualization and summary measures for business leaders from various industries. Highlights include performing data reduction techniques and survey analysis for Samsung, usability testing for Dexcom’s CGM, and Natural Language Processing of Amazon reviews of Batiste (Church and Dwight) dry shampoo.
Personal Projects
Designed a novel wins-loss model for Major League Baseball teams using K-Means clustering and Regression techniques. Model differed from actual results by 2.687 wins on average, beating most conventional wins-loss predictor algorithms on ESPN.
Camel Up is a board game based on horse-betting
I used Python to implement a virtual version of popular board game “Camel Up.” I then designed an algorithm to calculate the most optimal betting strategy based on game-state. Utilized to beat friends at the game.
Publications
Chang, H., Taylor, A., Ferariu, Ana., & Zhang, F., (2023). Investigating Biological and Brain Age in Children in the Adolescent Brain Cognitive Development (ABCD) Study. NeuroImage, 2023-09, under review.
Chang, H., Street, K., Ferariu, Ana., & Zhang, F., (2023). Biological Age Model using Weighted Intercepts Improves Multimorbidity Prediction in Children with Perinatally- Acquired HIV. Statistics in Medicine, 2023-09, under review.
Zhang, F., Chang, H., Schaefer, S. M., & Gou, J. (2022). Biological age and brain age in midlife - relationship to multimorbidity and mental health. Neurobiology of Aging, 132, 145-153.
https://www.sciencedirect.com/science/article/abs/pii/S0197458023002117?via%3Dihub
Niu, X., Gou, J., Chang, H., Lowe, M., & Zhang, F. (2022). Classification model with weighted regularization to improve the reproducibility of neuroimaging signature selection. Statistics in Medicine, 41(25), 5046-5060.
https://onlinelibrary.wiley.com/doi/10.1002/sim.9553
Shim, M., Kavanaugh, M., Lacson, C., Goldstein-Levitas, N., Chang, H., Zhang, F., Fisher, K., Connected through Movement - A Feasibility Study of Online Mindfulness-based Dance/Movement Therapy for Older Adults with Age-related Cognitive Decline during COVID-19. Aging and Mental Health, 2023-09, under review.
Presentations
Investigating Biological and Brain Age in Children in the Adolescent Brain Cognitive Development (ABCD) Study
May 2023
Invited 30 minute presentation at the annual Midlife in the US (MIDUS) Investigators Meeting at the University of Wisconsin, Madison
Investigating Biological and Brain Age in Children in the Adolescent Brain Cognitive Development (ABCD) Study
May 2023
Presented at Statistical Methods in Imaging (SMI) Conference at the University of Minnesota on May 2023