Top Selection Data Scientist

Senior Data Scientist at Top Selection, salary 300,000-320,000 RUB/month, remote work available. Build and optimize mathematical models, run A/A/B tests, mentor juniors.

Responsibilities: - Selecting and building suitable mathematical models for assigned tasks - Choosing optimal solution architecture for product tasks - Identifying and eliminating product weaknesses - Finding product growth points - Synthesizing optimal mathematical models for product tasks - Close interaction with business customers, consultants, and team - Setting up and conducting A/A, A/B, A/B/N experiments - Maintaining the product codebase and keeping it at a high level - Setting tasks and monitoring their execution by other analysts - Coordinating solutions with management - Presenting and defending results - Mentoring Junior and Middle analysts

Requirements: - Relevant education or certificates in data analysis and machine learning - 3+ years of experience in data science - Python (PEP 8) with ability to write code to quality standards - Knowledge of standard algorithms and data structures - Proficiency in data analysis libraries and numerical methods - Ability to write time- and memory-optimal code, algorithm complexity, debugging and optimization - Test-driven development - Strong OOP skills - Experience in project architecture design - Scheduling processes (airflow, cron) - Deploying projects to production - Experience with CI/CD - SQL basics (join, group by) - Experience with relational databases - Experience with PySpark (broadcast join, Spark UI) - Data skepticism and validation - Ability to implement any query, knowledge of window functions, identify non-optimal queries - Understanding pros and cons of different database types - Experience building ETL pipelines - Ability to design database structures - Working with query plans, transactions/ACID/indexes - Basic probability and statistics, A/B testing concepts, hypothesis testing - Classical ML methods, full A/B test lifecycle - Advanced hypothesis testing: multiple comparisons, parametric/non-parametric methods, bootstrap - Advanced ML models: Bayesian models, PGM, VBI, RL, etc. - Variance reduction methods in experiments - Intuition about data noise and independent groups - Analyzing effects without control/test groups - Experience writing articles, speaking at conferences - Experience with well-described tasks - Building analytical reports with given requirements - Presenting analytical findings and validated hypotheses - Understanding product metrics, translating business tasks into DS/DA/DE, decomposing complex tasks, building proxy metrics - Forming new research directions - Identifying strengths/weaknesses of product business logic - Experience consulting and working closely with product/business owners - Decomposing business goals into stories for analysis, estimating timelines - Ability to set tasks for mid-level analysts Stack: Python, SQL, data visualization (matplotlib, seaborn, plotly/BI tools), Git, PyTest, Spark 2.2+, Grafana/Airflow, Docker, Kubernetes (K8S)

Salary: from 300,000 to 320,000 RUB per month. Work format: remote possible.