Topfolio
Career TracksMicro Free CoursesTask CoursesPracticeInterview PracticeWork ExperienceProjects
Career TrackBlog
Support
Dashboard
Career TracksMicro Free CoursesTask Courses
SQL & Python
Interview Prep
Work ExperienceProjectsResume Feedback
CertificatesMy OrdersRefer & Earn
Join Community

Navigation

Dashboard
Learn
Career TracksMicro Free CoursesTask Courses
Practice
SQL & PythonInterview Prep
Career
Work ExperienceProjectsResume Feedback
My Stuff
CertificatesMy OrdersRefer & Earn
Join Community
Topfolio

Learn data analytics online. Real skills, real projects, real community.

courses

  • Career Tracks
  • Work Experience
  • Best Data Analyst Course in India
  • SQL Fundamentals
  • SQL Advanced
  • Python for Data
  • Micro Free Courses

practice

  • SQL Fundamentals Interview Test
  • SQL Advanced Coding Test
  • All Practice Tests

resources

  • How to Become a Data Analyst
  • SQL Interview Questions
  • Data Analyst Salary Guide
  • Free Datasets for Practice
  • SQL vs NoSQL Guide
  • Data Analyst vs Data Engineer vs Data Scientist

employers

  • Enterprise Screening
  • AI Proctoring Demo
  • Volume Pricing
  • Employer Portal

company

  • About
  • Terms
© 2026 Topfolio. All rights reserved.Made with ❤️ for aspiring analysts
Topfolio
Career TracksMicro Free CoursesTask CoursesPracticeInterview PracticeWork ExperienceProjects
Career TrackBlog
Support
Dashboard
Career TracksMicro Free CoursesTask Courses
SQL & Python
Interview Prep
Work ExperienceProjectsResume Feedback
CertificatesMy OrdersRefer & Earn
Join Community

Navigation

Dashboard
Learn
Career TracksMicro Free CoursesTask Courses
Practice
SQL & PythonInterview Prep
Career
Work ExperienceProjectsResume Feedback
My Stuff
CertificatesMy OrdersRefer & Earn
Join Community

Two-Proportion Z-Test & Confidence Interval

advanced~14 min35 pts
📊 View Insights

Problem

You're the analyst supporting a subscription SaaS company's growth team. They redesigned the signup page and ran a two-week A/B test:

  • Control (old page): 1,230 conversions out of 10,000 visitors
  • Treatment (new page): 1,310 conversions out of 10,000 visitors

Compute the absolute lift, run a two-sample z-test for proportions, and compute a 95% confidence interval on the difference (treatment − control).

Return a dict result with keys absolute_lift, z_stat, p_value, ci_low, ci_high — all rounded to 4 decimal places.

A/B TestingHypothesis TestingConfidence IntervalProportions
📊
📊 View Question Telemetry & Insights
Failure rate, silent bug autopsy & optimal query construction
Inspect →

Master SQL & Data Analytics

Ready to take your skills to the next level? Enroll in our comprehensive Data Analyst Career Track to master SQL, Python, Excel, and Power BI.

Explore the 12-Week Data Analyst Career Track

Related questions

  • Sample Ratio Mismatch (SRM) Checkintermediate
  • A/B Test Sample Size Calculatorintermediate
  • Select a Single Columnbeginner
  • Select Multiple Columnsbeginner
  • Filter Rows by Conditionbeginner
  • Filter with Multiple Conditionsbeginner
  • Sort DataFrame by Columnbeginner
  • Get Top N Rowsbeginner
Python Editor

Run your code to see the result here.

Topfolio

Learn data analytics online. Real skills, real projects, real community.

courses

  • Career Tracks
  • Work Experience
  • Best Data Analyst Course in India
  • SQL Fundamentals
  • SQL Advanced
  • Python for Data
  • Micro Free Courses

practice

  • SQL Fundamentals Interview Test
  • SQL Advanced Coding Test
  • All Practice Tests

resources

  • How to Become a Data Analyst
  • SQL Interview Questions
  • Data Analyst Salary Guide
  • Free Datasets for Practice
  • SQL vs NoSQL Guide
  • Data Analyst vs Data Engineer vs Data Scientist

employers

  • Enterprise Screening
  • AI Proctoring Demo
  • Volume Pricing
  • Employer Portal

company

  • About
  • Terms
© 2026 Topfolio. All rights reserved.Made with ❤️ for aspiring analysts