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I'm a data scientist.

ChatGPT-4o’s Perspective of What I Do:
 

“Ender connects the dots between data and human behavior — turning Python into clarity, dashboards into decisions, and pull-ups into balance.”

   • 5+ years of experience applying analytics and machine learning to solve business challenges.

   • Led projects in product segmentation, sales forecasting, and recommender systems.

   • Ranked 1st in class at Sabancı University (BSc GPA 3.93 / MSc GPA 3.95), where my Master’s thesis         focused on data-driven inventory and production decision-making for a major tire manufacturer.

   • Skilled in Python, R, SQL, advanced statistical methods, and data visualization.

   • Passionate about calisthenics, jump roping, and maintaining a healthy lifestyle.

   • Deeply interested in reading about cognitive biases, logical fallacies, and decision-making.

• Led analytics projects by analyzing large-scale search logs and user behavior using Python, SQL, clustering, and statistical modeling to uncover trends, track key metrics (e.g., DAU, CTR), and guide data-driven improvements to search quality through experimentation and cross-functional collaboration.

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• Designed and led the SBS-NPS project to evaluate search quality through statistical analysis of human-labeled comparisons, transforming qualitative judgments into a reliable metric for experimentation, evaluation, and product improvement.

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• Built automated data pipelines and dashboards to collect, validate, and visualize key evaluation metrics, ensuring data quality, transparency, and actionable feedback across the search quality workflow.

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Yandex Search Turkey
2024 - Present

Afiniti 
2022 - 2024

•  Developed machine learning models to personalize agent-customer interactions using Python, SQL, and R, leveraging large-scale behavioral data to predict preferences and rank call recommendations.


• Applied data mining, feature engineering, A/B testing, and statistical bootstrapping to enhance model accuracy and robustness in a real-time production environment.


•  Collaborated with research scientists and engineers to refine recommendation logic, contributing to a 5% increase in sales revenue.

Brisa
2020 - 2022

• Applied the CRISP-DM framework to lead end-to-end analysis of inventory and sales data, aligning stock keeping unit (SKU) strategy with production and business goals using Python.


• Designed and implemented a scoring-based SKU prioritization system using unsupervised learning techniques to support production planning.


• Performed scenario and counterfactual analysis, along with simulation studies, to evaluate the impact of prioritization strategies, enabling data-driven production decisions and reducing excess inventory by 20%.

Unilever
2018-2020

• Designed a hybrid forecasting framework that combined machine learning models with human expertise to improve inventory planning and forecast accuracy across product lines.

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• Conducted empirical research on human intervention in algorithmic forecasting, identifying when to rely on automation, human judgment, or a human-in-the-loop approach.

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• Optimized forecasting performance by segmenting products based on predictability and business context, leading to more accurate inventory decisions and reduced planning errors.

Philip Morris SA 
2018

• Designed and deployed a data-driven web interface with real-time dashboards to support strategic planning and sales decision-making. View Project Report

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Developed sales forecasting models using historical demand data and applied predictive techniques, including power, logarithmic, exponential, and polynomial regression, improving forecast accuracy by 10%.

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• Applied association rule mining (market basket analysis) to identify frequently co-purchased products, informing van loading strategies that reduced logistics costs and improved retailer satisfaction.​

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