

Callum Ballard
London-based Data Scientist & Machine Learning engineer, passionate about crafting and telling stories with data. Experienced in creating and communicating actionable insight to inform strategy, and managing projects and people in a high performing business environment. Tap icons below to view experience in detail.
Experience



Education



Key Skills
Data Science & Technical Skills
People & Project Management
Presenting & Client Management
Personal

McKinsey & Company - Finalta
Senior Manager
Jul 2018 – May 2019
- Developed, launched, and project managed Finalta’s Digital Telco benchmark – the company’s first ever product outside financial services – which identifies and quantifies opportunities in eCommerce and digital servicing for telecommunications companies.
- Responsible for commercial relationships across a number of markets (c.20 operators across the EMEA region currently participating in project).
- Line-manager to team of analysts, and responsible for training junior colleagues in both technical skills and knowledge.
Manager
Feb 2018 – Jul 2018
- Wrote and autonomously presented recommendation-driven key findings reports as part of workshops delivered to client board members and senior management.
- Redesigned Finalta’s largest existing benchmarking project, which analyses Digital & Multichannel performance for over 200 retail banks across the globe.
Consultant
Jan 2017 – Feb 2018
- Produced Finalta’s keynote document exploring global trends and best practices in digital banking, presented globally at various McKinsey & Co. conferences.
- Created pieces of analysis from large data sets to produce original insights, used to generate strategic recommendations to be implemented by clients.
- Managed the production and maintenance of analysis for Finalta’s global benchmarking studies, using Excel models and internally developed software.
- Responsible for data collection, and conducting research calls with key client stakeholders.
Senior Analyst
Jan 2016 – Jan 2017
- Voted as Finalta's "Most Supportive Analyst Colleague" by peers.
Analyst
Jan 2015 – Jan 2016
Associate Analyst
May 2014 – Jan 2015
Towards Data Science
Data Journalist
Jun 2019 – Present
- Freelance writer for Towards Data Science, one of the internet's most popular data science publications, with over 8 million monthly viewers.
- Articles can be found at Towards Data Science.
The Economist
Freelance Business Journalist
Jun 2013 – Jul 2013
- Published in The Economist newspaper’s business section, having made contacts and conducted interviews with subject experts in both the UK and USA.
- Writing can be found on The Economist website.
Flatiron School
Data Science & Machine Learning Student
May 2019 – Mar 2020
- Studied Flatiron School's comprehensive, MSc. style Data Science & Machine Learning course.
Module 1: Data Handling
- Extensive use of SQL, and Python Libraries such as Numpy and Pandas, Matplotlib, and Scikit Learn.
- Data cleaning and EDA techniques.
- Webscraping and API access with Requests, Beautiful Soup, and Splinter.
- Python APIs for NoSQL databases, such as MongoDB and JSON file structures.
Module 2: Statistics & Hypothesis Testing
- Statistical theory, Combinatorics, Bayesian statistics, T-Tests, Chi-Squared Tests, A/B testing etc.
- Permutation testing with Monte Carlo simulations.
- Basic regression techniques, including linear, polynomial, Ridge/Lasso, and model evaluation.
Module 3: Machine Learning
- Theory and implementation of classification models, including logistic regression, decision trees, ensemble methods such as random forests and XGBoost, and support vector machines.
- Hyperparameter tuning with GridSearchCV, and pipeline building.
- Un-supervised clustering algorithms, including k-nearest neighbours and Hierarchical Agglomerative Clustering.
- Graph theory with NetworkX.
Module 4: Big Data
- Machine learning in Pyspark using Docker.
- Recommendation systems using collaborative filtering.
Module 5: Deep Learning
- Theory and implementation of neural networks using Keras (both densely connected and convoluted networks for image recognition).
- Natural Language Processing and Word Embeddings using NLTK and Word2Vec.
London School of Economics
BSc. Mathematics & Economics (Joint Hons.)
Sep 2010 – Jun 2013
- Received an Upper Second Class degree in LSE's rigorous Mathematics & Economics joint honours degree programme.
- Achieved First Class scores in the following modules:
- Applications of Abstract Algebra
- Discrete Mathematics
- History of Industrialisation and Economic Growth
- President of LSE's Ultimate Frisbee team, which competed at national and international level.
Toot Hill School & College
A-Levels
Sep 2007 – Jun 2009
- A Grades in Mathematics, Further Mathematics, and Chemistry.
- Achieved Toot Hill's highest scores in both Mathematics and Further Mathematics for that academic year.
GCSEs
- 6 A* grades (Including English, Mathematics and Sciences), 3 A grades, and 1 B grade.
Data Science & Technical Skills
I have extensive experience translating datasets into actionable business insights and strategic recommendations.
- Proficient in SQL, Python and associated libraries including SQLite3, Pandas, scikit-learn, Keras, NumPy, NetworkX
- HTML, CSS, Webscrapers including Requests, BeautifulSoup4, and Splinter
- Data visualisation packages including Tableau, Matplotlib, Seaborn, and ThinkCell
- Produced personal website with Flask, and deployed with Heroku
- Experience in running hypothesis tests and other statistical methods.
- Regular contributer to Towards Data Science, one of the internet's most popular data science publications, with 300,000 subscribers, and over 8 million monthly viewers.
- Analytical style takes a "so what?" approach, using McKinsey's MECE technique, and ensuring that insights are actionable.
People & Project Management
As Senior Manager at McKinsey & Co, I had experience managing both projects and people.
- Independently managed projects, requiring the creation, implementation, and maintanance of project plans.
- Managed projects using 'sprint'-like philosophy, identifying key tasks across the team on a week by week basis and ensuring their completion.
- Line managed a team of analysts, and took steps to ensure their professional development. This included weekly catch ups to monitor progress and address concerns.
- Undertook extensive coaching training.
Presenting & Client Management
I was responsible for managing multiple clients at a project sponsor level, and presenting our findings to senior, non-technical audiences.
- Managed relationships with 40+ clients during my tenure, often working with 10+ clients simultaneously.
- Ran multiple workshops (at least one for each client) where I presented our key findings to very senior stakeholders (e.g. Heads of Digital, Heads of Retail Banking, etc.)
- Presented our work at industry conferences in the EMEA region.
Minor Royals 🤘
Minor Royals is a London-based five-piece band, writing and recording original music. I play bass guitar, and sing some backing vocals.
Our music is available on Spotify, Apple Music, and Bandcamp, amongst other streaming services globally. I create the band's artwork, run our social media presence, and work with venues and promoters to organise gigs.
