Strong quality metrics can be misleading when cost is ignored. The Measuring Campaign Efficiency module covers the Efficiency phase of the Growth Framework, teaching you how to evaluate campaigns by comparing what you spend against what you get back. Using Mixpanel's demo eCommerce dataset, you'll analyze Total Ad Spend, Cost Per Click, and Return on Ad Spend (ROAS) to identify which campaigns are genuinely profitable — and which ones only look efficient on the surface.