helen-oy.github.io/portfolio
Data Science: Python, SQL, R, Machine Learning, Azure Databricks, Google Cloud Platform (GCP), CI/CD, Github Actions.
Analytics: PowerBI, Tableau, Microsoft Excel, Azure Data Studio, Looker.
| MSc., Data Science | University of Nottingham |
| BEng., Engineering | Federal University of Agriculture, Abeokuta, Nigeria. |
Data Scientist @ Business Full Spectrum (Jan 2025 - Present)
Project Analyst @ MRS Oil and Gas (July 2022 – August 2023)
Data Scientist @ Hamoye AI Labs (Jan 2022 - April 2022)
Business Goal The goal was to reduce customer response time and agent workload by automating replies to routine support queries on social media while maintaining high response quality.
What I Did I cleaned and reconstructed historical tweet conversations into Q→A pairs, built a retrieval pipeline using FAISS, and integrated a RAG architecture with an LLM to generate responses grounded in real past interactions. I also created lexical filters to distinguish true unresolved cases from customer closure messages and designed evaluation metrics based on latency and response similarity.
What It Enabled This enables near-instant, consistent responses to common customer queries, reduces false identification of unresolved tickets, and allows human agents to focus only on complex issues requiring empathy, with a ~96% reduction in response time.
Business Goal The goal was to improve customer retention and marketing efficiency by identifying high-value customers and churn risk.
What I Did I used SQL and Python to perform RFM and cohort analysis, then built predictive CLV and churn models using XGBoost on over 600,000 customer records.
What It Enabled This supports targeted retention strategies focused on high-value, high-risk customers and better allocation of marketing spend.

Business Goal The goal was to measure churn trends and identify which customer segments were driving higher-than-acceptable churn rates.
What I Did I used SQL to calculate churn metrics over 72 months and built a Tableau dashboard to visualise churn by segment, contract type, and behaviour.
What It Enabled This allows stakeholders to quickly identify high-risk segments and prioritise targeted retention strategies.

Business Goal “The goal was to automatically classify large volumes of unstructured text into meaningful topics to understand public sentiment at scale.”
What I Did “I used Spark SQL and Spark ML to process high-volume tweet data and built a multinomial Naive Bayes model, comparing local modelling with a global self-supervised learning approach.”
What It Enabled “This enables organisations to automatically monitor customer or public feedback, identify key themes, and prioritise response strategies at scale.”

Business Goal The goal was to predict service delays and understand patterns affecting transport reliability.
What I Did I used K-means clustering to segment travel patterns and trained an ANN model to classify delay levels using historical bus movement data.
What It Enabled This allows transport operators to adjust scheduling and resources to improve reliability during peak congestion periods.

Business Goal The goal was to monitor support team performance and identify process improvements to reduce ticket backlog.
What I Did I built an interactive Looker Studio dashboard tracking ticket trends, resolution patterns, and departmental workload.
What It Enabled This helped identify where new hires and self-service options could reduce workload and improve response time.

Business Goal The goal was to monitor call centre performance and workforce efficiency using KPI metrics.
What I Did I built a reporting dashboard in Google Sheets tracking answer rate, abandon rate, and call trends over time.
What It Enabled This helped management understand peak periods, reduce abandon rates, and optimise staffing.

Business Goal The goal was to analyse sales performance, profitability, and product trends across regions.
What I Did I used SQL, DAX, and Power BI to build dashboards tracking revenue, profit, product performance, and regional trends over multiple years.
What It Enabled This allowed leadership to identify top-performing products, profitable regions, and yearly performance patterns.

Business Goal The goal was to translate large transactional data into clear sales and customer insights for decision-making.
What I Did I connected Tableau to a MySQL database and built dashboards showing KPIs, customer revenue contribution, and regional sales trends.
What It Enabled This helped management quickly identify key revenue drivers and customer segments contributing most to sales.

Business Goal The goal was to understand how product characteristics influenced sales performance.
What I Did I used Excel pivot tables and lookup functions to analyse breed characteristics, pricing, and quantity sold.
What It Enabled This informed which breeds to prioritise for stocking based on revenue potential rather than popularity.