Jedrzej Kardach
Verified Expert in Engineering
Data Scientist and Machine Learning Developer
Jedrzej is an accomplished full-stack data scientist and ML engineer with five years of experience. With strong Python back-end engineering skills, he excels in fast-paced, customer-value-centric work environments. Jedrzej collaborated with Princeton University's ORFE department to develop cutting-edge simulation environments to build sponsored search auction algorithms. Additionally, he has successfully delivered multiple NLP-based classification algorithms and reinforcement learning solutions.
Portfolio
Experience
Availability
Preferred Environment
MacOS, Jupyter Notebook, PyCharm, Python, Django, Machine Learning, Deep Learning, TensorFlow, Scikit-learn, Pandas
The most amazing...
...thing I have accomplished is obtaining a 5-fold improvement in the performance of a model created by a specialist with two levels of seniority above me.
Work Experience
Machine Learning Engineer
Kalepa
- Delivered an NLP binary classification model involving both topic classification and named entity recognition, achieved a 5-fold improvement in F1 score over the predecessor, defined target variables, and supervised labeling efforts.
- Rolled out multiple multi-label NLP classification models for drawing insights about business entities from large unstructured textual data.
- Built an information retrieval algorithm from large, unstructured textual data.
- Maintained the back-end infrastructure for models and deployed them using serverless AWS Lambda, AWS Step Functions, and Amazon SageMaker.
- Integrated ChatGPT API into the company's client-facing services, which included prompt engineering to maximize ChatGPT's utility for a given use case.
Data Scientist
Booksy
- Developed an event-based product monitoring architecture for parts of the application, designed performance monitoring for A/B tests, and suggested improvements to the product resulting in a 30% increase in B2C acquisitions.
- Designed and implemented ETL pipelines and machine learning models for churn prediction and user clustering.
- Delivered business intelligence dashboards using Microsoft Power BI, SQL, and BigQuery.
Data Scientist
Ora Ai
- Conducted a yearlong R&D process with the operations research and financial engineering department at Princeton University, which focused on developing a simulator of Google Ads environment for policy testing in a reinforcement learning setting.
- Built countless machine learning-based modules to forecast time series, solve regression and classification problems, or approximate values of specific metrics. All these modules aid the main bidding algorithm in making final bidding recommendations.
- Participated in the development of AI technology that optimally manages the bidding process in sponsored search auctions alongside researchers from Princeton University.
- Collaborated in the development of a simulator for a hotel economic environment using the Monte Carlo method that allowed testing algorithms for automated marketing.
- Co-developed reinforcement learning algorithms for automated marketing in hotels. This included setting an optimal price on special offers and choosing the right communication channel and time.
- Co-created a web application that facilitates the supervision of digital marketing campaigns as well as the AI that manages these campaigns.
- Developed a Django REST API and an ETL pipeline for real-time data collection from the hotel management software.
Experience
Optimal Motivation Scheme System for a Call Center
https://www.cambridge.org/engage/miir/article-details/61831286ad7f7c742d5411f5Skills
Languages
Python, Python 3, SQL, Java
Libraries/APIs
Scikit-learn, Pandas, NumPy, Matplotlib, XGBoost, TensorFlow, Django ORM, SQLAlchemy, Keras, TensorFlow Deep Learning Library (TFLearn), Natural Language Toolkit (NLTK), Google AdWords, SciPy, Requests
Tools
Seaborn, Jupyter, PyCharm, Git, GitHub, BigQuery, Postman, Bitbucket, AWS Step Functions, ChatGPT, Amazon SageMaker, Jira, Confluence, Microsoft Power BI, Docker Hub, Docker Compose, Plotly, Pytest
Paradigms
Data Science, ETL, Business Intelligence (BI), REST, Linear Programming
Platforms
MacOS, Jupyter Notebook, Amazon Web Services (AWS), AWS Lambda, Firebase, Google Cloud Platform (GCP), Docker, Amazon EC2, NoCodeAPI
Other
Data Mining, Machine Learning, Natural Language Processing (NLP), Logistic Regression, Linear Regression, Data Inference, Classification, Text Classification, Text Mining, Simulations, Clustering, K-means Clustering, Learning, Artificial Intelligence (AI), Data Scientist, Data Analysis, Data Analytics, Predictive Modeling, Data Modeling, Classification Algorithms, Programming, Modeling, Algorithms, Random Forests, Support Vector Machines (SVM), Decision Trees, Gradient Boosted Trees, Time Series, Time Series Analysis, Data Structures, Deep Learning, Hyperparameters, Web Scraping, APIs, Google BigQuery, User Monitoring, Real-time Bidding (RTB), Online Bidding, Reinforcement Learning, Bayesian Statistics, Predictive Analytics, Forecasting, Data Visualization, OpenAI GPT-3 API, Language Models, GPT, Generative Pre-trained Transformer 3 (GPT-3), Data-driven Marketing, Pricing Models, Dashboards, Analytical Dashboards, OpenAI GPT-4 API, Exploratory Data Analysis, Linear Algebra, Statistics, Statistical Methods, Probability Theory, Optimization, Partial Differential Equations, Finance, Mathematics, Analysis, Mathematical Analysis, Cryptography, Discrete Mathematics, Operations Research, Sorting Algorithms, Random Forest Regression, Support Vector Regression, Decision Tree Regression, Ad Optimization, Google Ads, Dash, Web Dashboards, Dashboard Design, Bayesian Inference & Modeling, Information Retrieval, Data Collection, Generative Pre-trained Transformers (GPT), Interactive Dashboards, Integration, Consumer Behavior
Frameworks
Django, Django REST Framework, Flask
Storage
PostgreSQL, MySQL, SQLite, Docker Cloud, Amazon S3 (AWS S3)
Industry Expertise
Project Management
Education
Master's Degree in Mathematics
The London School of Economics and Political Science (LSE) - London, United Kingdom
Bachelor's Degree in Mathematics
King's College London - London, United Kingdom
Certifications
Project Management Advanced Topics
Project Management Institute (PMI)
Project Management Fundamentals
Project Management Institute (PMI)
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