Causal Inference Scientist, Search Ranking & Experiments

Functional Software Stockholm AB; Malmö kommun; On-site; SEK 900,000 - 1,300,000; Full time

Job summary

Functional Software Stockholm AB in Malmö seeks a senior statistics and causal inference expert to design experiments and analyze ranking performance in a production search system.

You will work with ML and Search engineers on experimental design, causal methods, and online/offline evaluation, translating results into actionable guidance for product teams. Fluent English required; Swedish a plus.

Qualifications

• Advanced degree in quantitative field (Statistics/ Econometrics/Applied Math).
• 8+ years of development experience with a strong causal inference focus.
• Strong grounding in classical statistical modeling and uncertainty quantification.
• Experience analyzing large-scale behavioral data (search logs, clickstreams).
• Proficiency in Python or R for independent analysis, not necessarily production code.

Responsibilities

• Design experiments (A/B tests, interleaving, quasi-experiments) for ranking and relevance changes.
• Apply causal inference methods to observational data where randomization is impractical.
• Diagnose confounding, selection bias, and interference in search experiments and metrics.
• Collaborate with ML and search engineers to interpret model behavior statistically.
• Develop models of user behavior and search outcomes to support offline evaluation.
• Communicate findings and caveats clearly to engineers and product stakeholders.
• Advise on experimentation infrastructure, guardrails, and sample ratio mismatch checks.

Skills

Statistics

Causal inference

Experiment design

Programming (Python/R)

Communication

Education

MS/PhD in Statistics or related field

Tools

DoWhy

EconML

CausalImpact

Job description

Functional Software Stockholm AB in Malmö seeks a senior statistics and causal inference expert to design experiments and analyze ranking performance in a production search system.

You will work with ML and Search engineers on experimental design, causal methods, and online/offline evaluation, translating results into actionable guidance for product teams. Fluent English required; Swedish a plus.