Great explanations. For people, who prefer excel we have a calculator as an excel sheet: http://visualwebsiteoptimizer.com/split-testing-blog/ab-testing-signifi

Great explanations. For people, who prefer excel we have a calculator as an excel sheet: http://visualwebsiteoptimizer.com/split-testing-blog/ab-testing-significance-calculator-spreadsheet-in-excel/ http://visualwebsiteoptimizer.com/split-testing-blog/ab-test... We also have a blog post that explains mathematics of A/B testing: http://visualwebsiteoptimizer.com/split-testing-blog/ab-testing-significance-calculator-spreadsheet-in-excel/ http://visualwebsiteoptimizer.com/split-testing-blog/ab-test...