AgentSkillsCN

a-b-test-analyzer

以严谨的统计方法分析A/B测试结果。计算显著性水平、置信区间、样本量要求,以及业务影响。清晰得出胜出方案,并提出切实可行的改进建议。

SKILL.md
--- frontmatter
name: a-b-test-analyzer
description: Analyze A/B test results with statistical rigor. Calculates significance, confidence intervals, sample size requirements, and business impact. Generates clear winner declarations and actionable recommendations.
license: MIT
tags: [analytics, experimentation, ab-testing, statistics, optimization]

A/B Test Analyzer

Overview

Rigorously analyze A/B test experiments using statistical methods to determine winners, validate significance, calculate business impact, and generate clear, decision-ready reports for product and growth teams.


When to Use

  • Evaluating the results of a pricing page test (variant A vs B)
  • Analyzing email subject line A/B tests for open rate lift
  • Determining if a product feature change improved conversion rates
  • Checking if enough traffic was collected to reach statistical significance
  • Presenting experiment results to stakeholders with clear business impact

Instructions

  1. Accept inputs: control data (impressions, conversions, revenue), variant data, confidence level (default 95%), primary metric, secondary metrics.
  2. Validate minimum sample size: calculate required sample size based on baseline conversion rate, MDE (minimum detectable effect), and confidence level.
  3. Perform statistical significance test:
    • For conversion rates: two-proportion z-test.
    • For revenue/continuous metrics: Welch's t-test.
    • For count data: chi-squared test.
  4. Calculate: p-value, confidence interval for the difference, observed lift (%), relative lift (%).
  5. Check for statistical significance at the configured confidence level.
  6. Segment analysis: break down results by device, geography, user segment if data provided.
  7. Calculate business impact: projected annual revenue lift based on current traffic and conversion rates.
  8. Return decision: Winner (control/variant/no winner), statistical summary, business impact, and next steps recommendation.

Environment

code
CONFIDENCE_LEVEL=0.95
MINIMUM_DETECTABLE_EFFECT=0.05
TEST_TYPE=two_tailed
SEGMENTATION=true
OUTPUT_FORMAT=report|json

Examples

Input:

code
control:
  visitors: 12450
  conversions: 498
  revenue: 24900
variant:
  visitors: 12380
  conversions: 559
  revenue: 30745
primary_metric: conversion_rate
confidence_level: 0.95

Output:

code
A/B Test Analysis Report
Winner: VARIANT (statistically significant)
Control CR: 4.00% | Variant CR: 4.51%
Relative lift: +12.8%
p-value: 0.0031 (significant at 95% CI)
Confidence interval: [+0.21%, +1.01%]
Revenue per visitor: Control $2.00 vs Variant $2.48
Projected annual impact: +$562,000 (based on current traffic)
Recommendation: Ship variant to 100% of traffic