Carlos J. Gil Bellosta, Developer in Madrid, Spain
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Carlos J. Gil Bellosta

Verified Expert  in Engineering

Bio

Carlos is an experienced and highly versatile data scientist. He possesses a robust skillset covering applied statistics, Bayesian statistics, machine learning, R, Python, SQL, and other modern technologies. His career reflects his adaptability, having undertaken projects across a diverse range of industries: IoT, financial risk modeling, biotech, credit scoring, churn analysis, and digital marketing. Carlos's experience and skillset make him a valuable asset to any data-driven organization.

Portfolio

Circiter
R, Python, Statisticians, Data Science, eCommerce, ETL, Machine Learning...
SB Technology, Inc.
Python, Big Data, Data Science, Time Series Analysis, Trend Forecasting...
eBay
R, Python, Teradata, SQL, Spark, Data Science...

Experience

Availability

Full-time

Preferred Environment

R, Python, Scikit-learn, Statistics, Bayesian Statistics, Data Science, Forecasting, Time Series, PyMC, Marketing Mix Modeling

The most amazing...

...project I've developed involved creating a prediction model for COVID-19 medical device demand to optimize supply and ensure timely delivery to high-need areas.

Work Experience

CEO

2015 - PRESENT
Circiter
  • Created models to track and estimate flu, heat waves, and COVID-related deaths for the Spanish Ministry of Health.
  • Developed a system to optimize eCommerce campaigns, thereby minimizing customer impacts while maintaining an expected level of profitability.
  • Created a system to analyze customer flow in physical retail stores, which has been implemented in several big-name merchants with hundreds of stores in Spain.
  • Developed a churn analysis tool for a major security systems company in Spain.
  • Taught master's level courses in R and statistics in several universities (IE, EOI, UC3M, Complutense University of Madrid, and UNIR) and business schools (EAE and KSchool) in Spain, Peru, and Costa Rica.
  • Gave talks about machine learning, statistics, and big data in Spain, Colombia, Costa Rica, and Peru.
  • Developed models to predict product sales at a large dairy producer and a stock management and production optimization system.
  • Created tools and models to measure and improve keyword performance in Google Ads.
  • Developed tools and models to measure and improve the performance of keywords, ads, and targets for eCommercers on the Amazon platform.
  • Created tools and models to optimize the stock on Fulfillment by Amazon (FBA) for sellers on the platform.
Technologies: R, Python, Statisticians, Data Science, eCommerce, ETL, Machine Learning, Generative Pre-trained Transformers (GPT), Natural Language Processing (NLP), RStudio Shiny, Databases, JSON, Time Series Analysis, Data Science, Recommendation Systems

Data Scientist

2023 - 2024
SB Technology, Inc.
  • Developed several advanced AI prediction models for the demand for medical supplies.
  • Created advanced dashboards to track the model performance.
  • Achieved a 15-20% delivery efficiency and a 5-10% reduction in product disposal.
Technologies: Python, Big Data, Data Science, Time Series Analysis, Trend Forecasting, TensorFlow, R, RStudio Shiny, SQL, Bayesian Statistics

Senior Data Scientist

2014 - 2015
eBay
  • Developed tools to monitor the performance and engagement of new customers to the platform.
  • Created models to classify visits to the platform according to their browsing behavior, using novel techniques borrowed from natural language processing theory.
  • Played a key role in developing a company-wide platform to automate A/B testing and generate homogeneous campaign performance measures for all stakeholders.
  • Created tools to improve the performance of marketing campaigns.
  • Developed and maintained tools to detect fraud and illegitimate behavior of users in the platform.
Technologies: R, Python, Teradata, SQL, Spark, Data Science, Natural Language Processing (NLP), Generative Pre-trained Transformers (GPT), Machine Learning, OpenStack, Fraud Prevention, A/B Testing, eCommerce, Databases, Time Series Analysis, Data Science, Recommendation Systems

Statistical Consultant

2010 - 2014
Freelance
  • Participated in a large-scale ETL project in a major Spanish bank as part of the performance optimization team.
  • Developed the statistical engine for several laboratory data analysis workflows for a leading manufacturer of medical equipment.
  • Played a key role in the creation and first projects of one of the leading data analysis and data science working groups in Spain within BBVA, the global financial services group.
  • Assisted in the development of the R community in Spain, becoming the co-founder and serving as the first president of the association of Spanish R users.
  • Created a pioneering model, using the network of transactions among SMEs to predict their credit risk.
Technologies: Statisticians, R, SQL, Python, ETL, JSON, Time Series Analysis, Data Science

Senior Consultant

2009 - 2010
Everis Spain, S.L.U
  • Developed part of the internal analysis code for a financial risk management tool sold to several international banks.
  • Introduced modern code development standards for my team.
  • Created models for financial risk, especially credit risk for mortgages.
Technologies: R, SQL, MATLAB, Data Science, A/B Testing, Risk Models, Credit Risk, Market Risk

Statistical Consultant

2005 - 2009
Freelance
  • Implemented a SAS-based tool for Basel II compliance at Krung Thai Bank (KTB) in Thailand while serving as the main technical expert.
  • Implemented a SAS-based tool for Basel II compliance at Barclays Bank, London, as a member of a team of technical experts.
  • Provided technical support in the implementation of SAS risk management tools in several banks in Croatia, Belgium, and Pakistan.
Technologies: R, SAS, Risk Models

SAS Consultant

2004 - 2004
Bank of Spain (via Soluziona)
  • Maintained the SAS-based technological infrastructure in the bank supervision department at the Bank of Spain.
  • Improved the performance of the SAS code in the bank supervision department at the Bank of Spain.
  • Provided SAS support to several SAS projects within the Bank of Spain.
Technologies: SAS, SQL, Risk, Finance

SAS Consultant

2003 - 2004
SAS
  • Provided technical support in the sales process for SAS-related risk management products.
  • Developed models to assess the market risk of diverse portfolios, including financial and real assets in energy firms.
  • Beta-tested products for risk management during early development within SAS.
Technologies: SAS, Risk, Market Risk, Credit Risk, ETL

Demand Forecasting for Medical Supplies

I led a project to develop a large-scale prediction model for the demand for medical devices, which is crucial for optimizing their logistics and distribution. Leveraging machine learning techniques, I analyzed diverse data sources, including infection rates, healthcare capacities, and supply chain constraints. The model accurately forecasted the demand for these essential devices, enabling better resource allocation.

By integrating real-time data and predictive analytics, the model helped reduce shortages, minimize overstock, and ensure timely delivery of critical supplies to high-need areas. Collaboration with cross-functional teams, including healthcare professionals and supply chain experts, was key to refining the model's accuracy.

COVID-19 Mortality Model in Spain

An official application sponsored by the Ministry of Health to track COVID-related mortality in Spain. I developed the statistical models behind the application, which are based on a GAM Poisson model that includes controls for heatwaves, cold spells, age, sex, and other covariates.

Optimization of Email Marketing Campaigns

I created models to estimate openings, clicks, and conversions on email marketing campaigns at the customer level. Then I created a system to optimize the weekly number of sendings to minimize the number of contacts while maintaining the required profitability level of the individual campaigns.

HR Dashboard for a Global Consultancy Company

A global consultancy was interested in building an HR dashboard to provide information on its hiring funnel, which I created and maintained. I created a database that integrated data from different onboarding systems, integrated them in a combined database, and created dynamic reports and dashboards for the global, distributed HR team.

Retail Time Series Prediction

I implemented several state-of-the-art, large-scale prediction algorithms on thousands of sales-related time series for a major supermarket chain. I assessed their performance in terms of accuracy and other business goals, such as robustness, training speed, and maintainability.

Medical Device Data Analysis Project

I handled a data-centric project involving sensor data from several health-related devices. The data was properly cleaned, and an embedding was created from the raw signal data. These embeddings were then stored in a vector database for retrieval and analysis. Finally, to visualize and analyze the results, I developed a custom dashboard tailored to the project's specific needs.

Bid Optimization for Online Marketplaces

The customer is a large consultancy firm that specializes in eCommerce and marketplace strategies. I worked with them to create a model to optimize bids on online marketplaces for a variety of categories and products based on historical performance and using advanced SOTA time series prediction and Bayesian statistical methods.
1998 - 2003

Completed Ph.D. Coursework (ABD Status) in Statistics

Washington University in St. Louis - St. Louis, MO, USA

1997 - 1998

Master's Degree in Mathematics

Washington University in St. Louis - Saint Louis, MO, USA

1992 - 1997

Bachelor's Degree in Mathematics

University of Zaragoza - Zaragoza, Spain

Libraries/APIs

Scikit-learn, Caret, XGBoost, Pandas, NumPy, PyMC, TensorFlow

Tools

Jenkins, MATLAB, ARIMA, ARIMAX, Amazon QuickSight

Languages

R, Python, SQL, Snowflake, SAS

Frameworks

RStudio Shiny, Spark, Streamlit

Paradigms

ETL, Linear Programming

Platforms

Linux, Windows, H20, Google Cloud Platform (GCP), OpenStack, Kubernetes, Amazon Web Services (AWS)

Storage

Databases, JSON, Teradata, PostgreSQL, MySQL

Industry Expertise

Marketing, Retail & Wholesale, High-frequency Trading (HFT)

Other

Statisticians, Bayesian Statistics, Programming, Data Science, Time Series, Machine Learning, A/B Testing, Forecasting, Data Analysis, Data Engineering, Time Series Analysis, Data Science, Recommendation Systems, Stan, eCommerce, Natural Language Processing (NLP), Email Marketing, Finance, Generative Pre-trained Transformers (GPT), Principal Component Analysis (PCA), Epidemiology, Risk Models, Risk, Market Risk, Credit Risk, Biostatistics, Fraud Prevention, Marketing Mix Modeling, Supply Chain Management (SCM), Supply Chain Optimization, Custom Models, Statistical Analysis, Supply Chain, Big Data, Trend Forecasting, Handling Outliers, NumPyro

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