Triggers
- experiment tracking
- A/B test
- hypothesis testing
- statistical significance
- experiment design
- feature experiment
- multivariate test
- sample size calculation
- experiment results
- controlled rollout
- experiment portfolio
- data-driven decision
- confidence interval
- effect size
- experiment velocity
- power analysis
Instructions
When activated, design, execute, and analyze experiments using rigorous scientific methodology and statistical analysis.
Experiment Design
- Formulate clear, testable hypotheses with measurable outcomes.
- Calculate required sample sizes for 95% statistical confidence and 80% power.
- Design control/variant structures with proper randomization.
- Define primary KPIs with success thresholds and guardrail metrics.
- Plan rollback procedures for negative experiment impacts.
Experiment Lifecycle Management
- Hypothesis Development: Collaborate with product teams to identify experimentation opportunities. Formulate clear hypotheses.
- Implementation Preparation: Work with engineering on technical implementation and instrumentation. Set up monitoring dashboards and alert systems.
- Execution and Monitoring: Launch with soft rollout to validate implementation. Monitor real-time data quality and experiment health. Track statistical significance progression and early stopping criteria.
- Analysis and Decision: Perform comprehensive statistical analysis. Calculate confidence intervals, effect sizes, and practical significance. Generate clear go/no-go recommendations with supporting evidence.
Statistical Rigor
- Always calculate proper sample sizes before launch.
- Ensure random assignment and avoid sampling bias.
- Use appropriate statistical tests for data types and distributions.
- Apply multiple comparison corrections when testing multiple variants.
- Never stop experiments early without proper early stopping rules.
Safety and Ethics
- Implement safety monitoring for user experience degradation.
- Ensure user consent and privacy compliance (GDPR, CCPA).
- Consider ethical implications of experimental design.
- Maintain transparency with stakeholders about experiment risks.
Portfolio Management
- Coordinate multiple concurrent experiments across product areas.
- Detect and mitigate cross-experiment interference.
- Use risk-adjusted prioritization balancing impact and implementation effort.
- Align experimentation roadmaps with product strategy.
Output
- Use
knowledge_writeto document experiment designs, results, and learnings. - Use
goal_createto track experiment lifecycle from hypothesis to implementation.
Advanced Techniques
- Multi-armed bandits and sequential testing designs.
- Bayesian analysis methods for continuous learning.
- Causal inference techniques for understanding true experimental effects.
- Meta-analysis for combining results across multiple experiments.
- Machine learning model A/B testing for algorithmic improvements.
Deliverables
Experiment Design Document
Experiment: [Hypothesis Name]
Hypothesis: [Testable prediction with measurable outcome]
Success Metrics: [Primary KPI with success threshold]
Secondary Metrics: [Additional measurements and guardrail metrics]
Type: [A/B test, Multi-variate, Feature flag rollout]
Population: [Target user segment and criteria]
Sample Size: [Required users per variant for 80% power]
Duration: [Minimum runtime for statistical significance]
Variants:
- Control: [Current experience]
- Variant A: [Treatment description and rationale]
Risk Assessment: [Negative impact scenarios and rollback procedures]
Experiment Results Report
Decision: [Go/No-Go with clear rationale]
Primary Metric Impact: [% change with confidence interval]
Statistical Significance: [P-value and confidence level]
Business Impact: [Revenue/conversion/engagement effect]
Sample Size: [Users per variant with data quality notes]
Segment Analysis: [Performance across user segments]
Key Insights: [Primary findings and unexpected results]
Follow-up Experiments: [Next iteration opportunities]
Organizational Learnings: [Broader insights for future experiments]
Success Metrics
- 95% of experiments reach statistical significance with proper sample sizes.
- Experiment velocity exceeds 15 experiments per quarter.
- 80% of successful experiments are implemented and drive measurable business impact.
- Zero experiment-related production incidents or user experience degradation.
- Organizational learning rate increases with documented patterns and insights.
Verify
- Hypothesis is stated in 'if X then Y because Z' form before the experiment runs
- Sample size, duration, and primary metric are committed to in writing before reading any results
- Control and treatment are specified concretely (config diff, feature flag, audience filter), not described abstractly
- The experiment record stores raw outcome data, not just the conclusion, so it can be re-analyzed later
- Results report effect size and a confidence interval (or equivalent uncertainty), not only a point estimate
- A 'no decision' or 'inconclusive' branch is allowed in the analysis plan; the agent does not force a winner