Everything we have written about a/b testing.
A plain-English guide to the 4 statistics ideas behind most business reports, averages, variance, correlation and significance, with worked examples and Excel functions.
What conversion rate optimization is, a 5-step research-first CRO process and the common quick wins that help small business websites turn more visitors into customers.
A plain-English, step-by-step guide to A/B testing your website or emails: writing a hypothesis, estimating sample size, running the test and reading results honestly.
How feature flags work, the 4 main types teams use, and the cleanup habits that stop old flags turning into risky technical debt.
9 subject line formulas with examples, how to pair them with preview text, and the spammy habits that hurt deliverability or break the rules.