Juan Manuel Ortiz de Zarate
Data Scientist and Developer
Location
Ciudad de Buenos Aires, Buenos Aires, Argentina
Toptal Member Since
November 6, 2019
Currently, Juan is a PhD candidate at the University of Buenos Aires, researching the subjects of AI, NLP, and social networks. He has over a decade of professional development experience under his belt. For the last few years, he’s been immersing himself in various types of data science projects and loving every minute of it. Juan relishes taking on data problems, building prediction models, and learning state-of-the-art techniques.
Juan is available for hire
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Fundar
Artificial Intelligence (AI), Big Data...
Universidad de Buenos Aires
R, Python
Massomedia S.A.
Python, R
Experience
Data Science - 5 yearsMachine Learning - 4 yearsPython 3 - 3 yearsRStudio - 3 yearsJupyter Notebook - 3 yearsPandas - 2 yearsMatplotlib - 2 yearsScikit-learn - 2 yearsLocation
Availability
Part-time
Preferred Environment
RStudio, Jupyter Notebook
The most amazing...
...thing I've coded is a an entire web app to monitor social networks. It has a back end in R for statistics and a PHP front end.
Work Experience
2022 - PRESENT
Senior Data Scientist
Fundar
- Managed and supervised external students in their research.
- Managed a different kind of research project with internal and external members.
- Interviewed external collaborators and consultants to hire for specific projects and technical works.
Technologies: Artificial Intelligence (AI), Big Data, Generative Pre-trained Transformers (GPT), GPT, Natural Language Processing (NLP), Team Management, Hiring, Data Analysis
2017 - PRESENT
Ph.D. Student Researcher
Universidad de Buenos Aires
- Created new techniques to analyze discussions on social networks with R and Python.
- Predicted movie reviews using the IMDB database with R.
- Predicted implication clauses with NLP through Python models.
- Developed new techniques to predict controversy with NLP techniques on social networks with R and Python.
- Created new techniques to graph clusters with NLP techniques on social networks with Python and R.
Technologies: R, Python
2016 - PRESENT
Freelance Data Scientist Advisor
Massomedia S.A.
- Predicted presidential votes via telephone surveys using Python.
- Analyzed several discussions on Twitter and Facebook using R.
- Developed a web app using R, PHP, and MySQL to monitor social networks and media.
- Built a product with Python that could analyze telephone surveys about product sales.
- Presented the results, conclusions, and explanations for each task to the client.
Technologies: Python, R
2023 - 2023
R Specialist
Beryl Capital Management LLC
- Configured and installed a script to download and analyze data from brokers.
- Repaired broken R libraries to fix the financial script.
- Connected to the client's computer and chatted in real-time to test the script and apply all the fixes.
Technologies: R, RStudio, SharePoint, Financial Data, Stock Market, Bloomberg, Bloomberg Terminal, Bloomberg API
2022 - 2022
Front-end Developer
Nixtla Inc.
- Developed new and custom plugins in TypeScript for JupyterLab.
- Researched JupyterLab documentation to understand how to create new features.
- Documented the creation of the new features and how they can be extended and installed in new environments.
Technologies: CSS, TypeScript, Front-end, Jupyter, Jupyter Notebook, Data Science, Forecasting, JupyterLab
2021 - 2022
Technical Editor
Auth0
- Corrected and edited technical articles about the latest technologies implementations.
- Tested technological implementations described in the articles.
- Evaluated writers' applications from all over the world for the company writers program.
Technologies: Python 3, PHP, Technical Writing, Writing & Editing, Auth0, Authentication, Authorization
2020 - 2022
Head Teaching Assistant
University of Buenos Aires
- Acted as the head teaching assistant at Data Organization subject. In this subject, we try to introduce students to data science. This subject is part of the mandatory career plan for informatics engineering.
- Designed all of the subject content together with another professor. Due to the COVID-19 lockdown, all of the online classes (in Spanish) are available on YouTube; if you would like to view them, contact me for the link.
- Taught half of the theoric classes and half of the practical lessons. I also have to coordinate the teachers of the practical lessons and prepare and correct the final exams and practical works.
- Designed the final test and the practical work that students must be approved to complete the subject.
Technologies: University Teaching, Data Science, Education, Machine Learning
2021 - 2021
Data Scientist
Carrie Beam Consulting
- Created new functionalities in R to give a graph of financial relations suggesting new unions that improved trade between the actors.
- Optimized algorithms on graphs so that they can work on large data sets.
- Found bugs in existing R code and suggested better ones.
Technologies: Graphs, igraph, R, Networks, Computer Science
2020 - 2021
Teaching Assistant
Universidad Católica Argentina
- Composed practical lessons for the Data Science class.
- Corrected exams and practical homework for the Data Science subject.
- Tutored and answered questions from students in the Data Science topics.
- Explained machine learning techniques, regularizations methods, feature extraction and selection, data visualization methods, and more tasks related to data science.
Technologies: Data Science
2020 - 2020
Statistical Developer
Decentral Park Advisors LLC (via Toptal)
- Predicted Bitcoin 1D, 3D, and 7D returns with multinomial regressions and generalized additive models (GAMs).
- Predicted Bitcoin 1D, 3D, and 7D positive or negative values through classification models as randomForest, XGBoost, and Bagging.
- Reported the results through Jupyter Notebooks and R Shiny dynamic graphs.
Technologies: RStudio Shiny, R, Jupyter, Matplotlib, Pandas, Scikit-learn, Python
2020 - 2020
Data Analyst
LL Media, LLC (via Toptal)
- Standardized multiple information sources about leads using Python and Pandas.
- Scored the performance of each source over different kinds of campaigns using Python, Pandas, and Matplotlib.
- Predicted good leads by demographic data using machine learning classifiers scikit-learn.
- Predicted bad leads by demographic data using machine learning classifiers scikit-learn.
- Analyzed lead data to find simple correlations between good and bad lead performance.
Technologies: Matplotlib, Pandas, Scikit-learn, Python, Data Engineering
2017 - 2018
Teaching Assistant
Universidad de Buenos Aires
- Composed practical lessons for the Computer Structures 1 class.
- Corrected exams and practical homework for the Computer Structures 1 class.
- Tutored and answered questions from students in the Computer Structures 1 class.
Technologies: Structure, Computer
2016 - 2017
Teaching Assistant
Universidad de Buenos Aires
- Composed and gave practical lessons for the Network Theory class.
- Corrected exams and homework for the Network Theory class.
- Tutored and answered questions from students in the Network Theory class.
Technologies: Network Theory
2014 - 2015
Senior Full-stack Developer
Telam
- Developed and maintained a system for journalists, which allowed them to write different types of notes and publish them on the news site.
- Built and maintained a system to administrate the advertisement money.
- Developed a REST API to connect with other media news sites.
Technologies: JavaScript, MySQL, PHP, Back-end
2010 - 2014
Senior Full-stack Developer
Intraway
- Built and maintained a system for call center assistance.
- Developed and maintained features to communicate with the STB Systems and reset them.
- Constructed and supported a dynamic decision tree to give the best answers to clients based on their specific problems and configurations.
- Created and maintained an internal ticket system to organize tasks and assign them to different teams.
Technologies: jQuery, JavaScript, SQL, PHP, Back-end, Front-end
2008 - 2010
Principal Developer
Imprek
- Developed the company's administrative system.
- Built a system to administer technique services.
- Maintained the stock system.
- Implemented a system to print digital photos from a Kodak machine.
- Developed the company's financial system.
Technologies: JavaScript, MySQL, PHP
Experience
Data scientist at Fundar
I am a data scientist researcher at Fundar. Fundar is an organization dedicated to studying, researching, and designing public policies focused on developing a sustainable and inclusive Argentina. There I have worked for different government dependencies, such as the Ministry of Tourism, the presidential secretary, and more. Also, I had to direct research scholarships that the foundation grants to students from different universities.
Professor of Data Science at University of Buenos Aires
https://orga-de-datos.github.io/I designed all of the subject content together with another professor.
I was responsible for giving theoretical and practical classes, correcting and designing midterms, and taking final tests. Due to the COVID-19 lockdown, all of the online classes (in Spanish) are available on YouTube; if you would like to view them, contact me for the link.
I was responsible for giving theoretical and practical classes, correcting and designing midterms, and taking final tests. Due to the COVID-19 lockdown, all of the online classes (in Spanish) are available on YouTube; if you would like to view them, contact me for the link.
Technical Editor
https://auth0.com/blog/I should correct and review technical articles that different authors write for the Auth0 technology blog. The subject of the articles includes various fields: machine learning, security, developing frameworks, design patterns, and more.
I should also test the applications or code the authors develop in the article to see if they were well designed and implemented.
I should also test the applications or code the authors develop in the article to see if they were well designed and implemented.
Social Network Analysis in R and Gephi: Digging Into Twitter
https://www.toptal.com/r/social-network-analysis-in-r-gephi-tutorialIn this article, I show how to make a social network analysis using the Twitter API, R, and Gephi. By downloading a specific conversation, I build the social graph, plot it through a meaningful layout, and identify its principal communities.
Understanding Twitter Dynamics With R and Gephi: Text Analysis and Centrality
https://www.toptal.com/r/social-network-analysis-in-r-gephi-2In this second article, I applied centrality measures to detect the principal actors of the discussion and natural language processing techniques to understand what they are talking about in each community.
Ensemble Methods: The Kaggle Machine Learning Champion
https://www.toptal.com/machine-learning/ensemble-methods-kaggle-machine-learnTwo heads are better than one. This proverb describes the concept behind ensemble methods in machine learning. In this article, I examine why ensembles dominate ML competitions and what makes them so powerful.
A Glimpse Into the Future of Data Science
https://www.pangea.ai/data-science-resources/future-of-data-science/Data science is changing the world, it is at the heart of the fourth technological revolution. But how do we get here? How is the world changing? What else does this future hold?
In this article, I introduce the irruption of data science in our life, how we get here, some representative cases, and where we are going.
In this article, I introduce the irruption of data science in our life, how we get here, some representative cases, and where we are going.
10 Best Data Science Development Frameworks to Use in 2021
In a world where data is more valuable than oil, the demand for data scientists and analysts is skyrocketing. In this article, I present the best tools for tapping into these data reserves. Hands down, Python is the clear choice for any aspiring developer trying to break into the field of data analysis.
Predicting Presidential Elections Through Surveys
Through telephone surveys, I predicted the votes of undecided voters.
Using clustering and machine learning techniques, I detected to which political cluster the undecided persons were close. With that information, I could predict with high accuracy their vote.
Using clustering and machine learning techniques, I detected to which political cluster the undecided persons were close. With that information, I could predict with high accuracy their vote.
Application to Monitor Social Networks
I developed, on my own, an entire application to monitor social networks like Instagram, Facebook, and Twitter. It has statistics about any public account needed and sends messages/alarms to the client through a telegram if something important is happening.
It has a back end in R to download information, process it, and calculate statistics and a PHP front end to show the data. I also used C to manage sessions, create, delete, modify searches, and more.
It has a back end in R to download information, process it, and calculate statistics and a PHP front end to show the data. I also used C to manage sessions, create, delete, modify searches, and more.
Stars Realigned: Improving the IMDb Rating System
https://www.toptal.com/data-science/improving-imdb-rating-systemIMDb ratings have genre bias: Dramas tend to score higher, for example. Is there a way to remove such biases and discover what makes a movie unique?
In this article, I show you how to refine IMDb scores and create a better ranking system through data science and machine learning techniques.
In this article, I show you how to refine IMDb scores and create a better ranking system through data science and machine learning techniques.
Predicting Kindle Reviews
I have developed an NLP Model with Fasttext to predict if a kindle review will be positive, neutral or negative based on the text write by the users
Hiring Data Scientists — Best Practices and Job Description Template
Hiring an IT candidate is one of the hardest tasks that human resource professionals have to accomplish. Demand for IT professionals is greater than available individuals on the market, which produces competition between companies for the scarcely qualified developers.
In this article, I advise you on how to improve your candidates' research and hire the best profiles for your team.
In this article, I advise you on how to improve your candidates' research and hire the best profiles for your team.
Publication
Stars Realigned: Improving the IMDb Rating System
https://www.toptal.com/data-science/improving-imdb-rating-system
Publication
Ensemble Methods: The Kaggle Machine Learning Champion
https://www.toptal.com/machine-learning/ensemble-methods-kaggle-machine-learn
Publication
Social Network Analysis in R and Gephi: Digging Into Twitter
https://www.toptal.com/r/social-network-analysis-in-r-gephi-tutorial
Publication
Understanding Twitter Dynamics With R and Gephi: Text Analysis and Centrality
https://www.toptal.com/r/social-network-analysis-in-r-gephi-2
Publication
Mining for Twitter Clusters: Social Network Analysis With R and Gephi
https://www.toptal.com/r/social-network-analysis-in-r-gephi-3
Publication
Advantages of AI: Using GPT and Diffusion Models for Image Generation
https://www.toptal.com/artificial-intelligence/advantages-of-ai-gpt-image-generation
Skills
Languages
PHP 7, Python 3, R, SQL, JavaScript, CSS, Python, PHP, TypeScript, HTML
Frameworks
RStudio Shiny, CodeIgniter, .NET
Libraries/APIs
igraph, Scikit-learn, Matplotlib, Pandas, Keras, Ggplot2, NumPy, jQuery, Caret, Bloomberg API
Paradigms
Data Science, Test-driven Development (TDD)
Platforms
RStudio, Jupyter Notebook, Linux, WordPress, Oracle, Gephi, SharePoint, Bloomberg Terminal
Storage
MySQL
Other
Data Visualization, Charts, Social Networks, Social Network Analysis, Visualization Tools, OOP Designs, Machine Learning, Data Analytics, Data Analysis, Big Data, Time Series, Time Series Analysis, Clustering, Statistics, Code Review, Source Code Review, Team Management, Interviewing, Network Theory, Computer, Structure, Education, University Teaching, Stock Market, Stock Trading, Graphs, Networks, Computer Science, Writing & Editing, Hiring, Technical Writing, Authentication, Authorization, Back-end, Front-end, Data Engineering, Forecasting, JupyterLab, Natural Language Processing (NLP), Artificial Intelligence (AI), Blogging, Blog Posting, Technical Hiring, Financial Data, GPT, Generative Pre-trained Transformers (GPT)
Tools
Dplyr, Seaborn, Jupyter, Auth0, R Studio, Bloomberg
Education
2017 - 2022
Ph.D. Degree (in Progress) in Computer Science
Universidad de Buenos Aires - Buenos Aires, Argentina
2010 - 2016
Master's Degree in Computer Science
Universidad de Buenos Aires - Buenos Aires, Argentina
Certifications
DECEMBER 2018 - PRESENT
Deep Learning
Coursera
OCTOBER 2018 - PRESENT
Machine Learning
Coursera
SEPTEMBER 2018 - PRESENT
Laboratory of Machine Learning
ITBA | Instituto Tecnológico de Buenos Aires