Giannis Tolios | Freelance Data Scientist

Giannis Tolios

Freelance Data Scientist

Based in Thessaloniki, Greece

About

As an experienced data scientist and researcher, I am passionate about statistics and machine learning. I am particularly interested in utilizing data science to mitigate climate change, and help accomplish the UN Sustainable Development Goals. I am also a contributing writer at established websites such as Towards Data Science. Furthermore, I have published a book titled Simplifying Machine Learning with PyCaret, that quickly became a best seller and got cited in scientific papers. Feel free to send an email if you want me to work on your projects!

Skills

View CV

Projects

Simplifying Machine Learning with PyCaret (book)

A beginner-friendly introduction to machine learning with Python, that is based on the PyCaret and Streamlit libraries. Readers will delve into the fascinating world of artificial intelligence, by easily training and deploying their ML models.

Stats Europa

An interactive dashboard that provides statistical indicators and analysis about European Union countries, based on data from reliable sources sources like Eurostat and Our World In Data. You can easily view the graph of your preference by selecting an indicator, or visit the Analysis page.

Renewcast

A dashboard app that provides forecasts for renewable electricity generation in EU countries, based on Streamlit and PyCaret . Users can select the country and the forecasting model of their preference, ranging from classical approaches to machine learning models.

Atmospheric CO2 Forecasting

In this project, I am comparing the performance of various forecasting models, including classical, machine learning and deep learning approaches, by using the darts library . My goal is to create a forecast for the atmospheric CO2 concentration of 2022, based on the the Mauna Loa CO2 dataset.

Experience

2022 - 2023

Data Scientist at Dataphoria

As a sustainability data scientist in a dynamic startup, I accomplished the folowing: • I upgraded the company data infrastructure with a pipeline based on Airflow • I developed software, including Python analytics tools and dashboards. • I collaborated with stakeholders to create new projects for their needs. • I worked with a local govt. organisation to analyze and visualize their efforts. • I utilized statistics and machine learning to extract insights from raw data.

2023-2025

Senior Research - Consultant at E3Modelling

I performed quantitative research and data analysis, as part of the Global Integrated Assessment Modelling team of E3-Modelling. More specifically, I accomplished the following: • Developed energy systems modelling software with GAMS, R and Python. • Ι participated in the OPEN-PROM development team, upgrading model functionality. • I developed mrprom, an R package for data collection and processing. • I improved the development workflow, establishing DevOps for testing. • Participated in EU research projects, like NDC ASPECTS. • Contributed to research papers published by the Global IAM team. E3-Modelling models are heavily utilized by organizations like the European Commission and Intergovernmental Panel on Climate Change (IPCC), to help shape important climate policy initiatives.

2018 - 2026

Freelance Data Scientist

I am offering my services as a data scientist on the Upwork freelancing platform, mostly working with Python libraries, such as Jupyter, pandas, scikit-learn and PyTorch. I have collaborated with numerous companies in North America, Europe and Asia, managing to successfully complete various projects. Therefore, I have acquired significant experience in machine learning, time series forecasting, data visualization and other tasks. Here's a selection of my past completed projects: • Collaborated with a retailer to create a pipeline for their Snowflake data warehouse. • Developed a dashboard with visualizations and statistics about marketing. • Created a multivariate time series forecasting model for a fitness company. • Applied geospatial analysis and NLP on Airbnb datasets.

Education

Computer Science BSc at TEI of Central Macedonia

Computer Science MSc at University of Hertfordshire