What is A/B testing?
A/B testing is a method of comparing two or more versions of a product to determine which one performs better on given metrics. Its goal is to make decisions based on data, not assumptions.
How it works
- Two (or more) variants are created
- Variant A is the current (control) version.
- Variant B is the modified (experimental) version. For example: different button text, a different screen design, or a different recommendation algorithm.
- The audience is split randomly Each user sees only one of the variants. This rules out the human factor and makes the results objective.
- Data is collected Metrics are tracked: clicks, sign-ups, purchases, retention, conversion, and so on.
- Comparison and analysis Statistics are used to determine whether there is a significant difference between the variants. The winning variant is rolled out to the main version.
Where it's used
- UI/UX - buttons, text, colors, element placement.
- Marketing - email subject lines, banners, pages.
- Product decisions - pricing, recommendations, new features.
Important
- The test runs until statistical significance is reached (not based on "gut feeling").
- Parameters cannot be changed during the test, this distorts the result.
- The goal must be clearly defined in advance (for example, "increase sign-ups by 5%").
Conclusion
A/B testing is a tool for testing hypotheses that helps understand what actually works for users and make decisions based on facts, not intuition.
Short Answer
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