What I'm looking for is pretty simple but after half an hour on Google I still haven't found anything. What I need is a reliable statistical significance calculator to compare two samples. For example, say I'm comparing the performance of two landing pages: Page A had 5,000 visits and 500 people converted (completed the desired action); Page B had 5,500 visits and 490 people converted. Is Page A better than B with 80, 90, 95 or 99% confidence? Or are the results not statistically significant?
An online calculator, or even better, a spreadsheet would be extremely helpful. Thank you!
Looks like you want to find a calculator for performing a hypothesis test comparing two population proportions. Try this one http://epitools.ausvet.com.au/content.php?page=z-test-2