Tesing 1, 2, 3...

They disagreed, rolled out as planned ... and got drastically different results from the prior year.

You don’t need a degree in statistics to understand this simple rule: For a test to be valid, you need at least 50 responses (orders) in each cell. Any cell that gets fewer is meaningless.

And you can turn this around. When creating a test, plan to get at least 50 responses per cell. That’s the reason behind the 5,000-name minimum that most list rentals institute. A 1-percent response rate from 5,000 names will yield 50 orders — just enough to be statistically significant. If you’re expecting less than a 1-percent response rate, rent more names to bring your expected order quantity up to a minimum of 50 per cell.