Senior Applied Data Scientist - Large-Scale Entity Matching

Bain & Company; Warszawa; On-site; PLN 180,000 - 250,000; Full time

Job summary

Bain & Company in Warsaw is seeking a Senior Applied Data Scientist to advance entity matching at scale. You will develop and evaluate ML, embeddings, and LLM approaches to improve data quality and matching accuracy across large datasets.

You will collaborate with data scientists, data engineers, and software engineers to deploy production‑grade solutions, measure impact, and communicate results to stakeholders.

Qualifications

• 5–8 years of relevant professional experience in applied data science, machine learning, or a related field.
• Strong applied machine learning expertise, including hands‑on experience building and evaluating models using real‑world data
• Excellent Python and SQL skills
• Practical experience with embeddings, semantic similarity, LLMs or related AI techniques
• Hands‑on experience training supervised and unsupervised models, including classification and NLP applications
• Working knowledge of neural networks and transformer architectures
• Experience with machine learning frameworks such as TensorFlow, PyTorch, or PyCaret
• Experience retraining taxonomy classifiers or maintaining classification models in production
• Strong experimental judgment, including the ability to define baselines, evaluation metrics, test sets, and error analyses
• Ability to clearly explain model behavior, technical trade‑offs, and edge cases to engineering and business stakeholders

Responsibilities

• Develop Smarter Entity Matching using machine learning, embeddings, and LLM‑based approaches.
• Evaluate data quality for entity matching, including name variations, domains, multilingual records, and firmographics.
• Develop scoring and ranking approaches to distinguish genuine matches from lookalikes and duplicates.
• Evaluate AI techniques balancing accuracy, scalability, and cost.
• Design scalable production solutions and collaborate with engineers to deploy prototypes.
• Provide clear model specifications, evaluation results, edge cases, and rollout criteria.
• Measure impact, diagnose regressions, and suggest improvements to models and matching logic.
• Communicate trade-offs across model quality, scale, cost, latency, explainability, and risk.

Skills

Python

SQL

Machine learning

Embeddings

LLMs

NLP

TensorFlow

PyTorch

PyCaret

Data science

Entity resolution

Tools

Spark

Snowflake

Databricks

BigQuery

Job description

Bain & Company in Warsaw is seeking a Senior Applied Data Scientist to advance entity matching at scale. You will develop and evaluate ML, embeddings, and LLM approaches to improve data quality and matching accuracy across large datasets.

You will collaborate with data scientists, data engineers, and software engineers to deploy production‑grade solutions, measure impact, and communicate results to stakeholders.