So this is the same thing as the mean of population 1 minus the mean of population 2. And this was the neat result about the last video. This isn't just a 95% confidence interval for this parameter right here, it's actually a 95% confidence interval for this parameter right here. And this is the parameter that we really care about. The true difference in weight loss between going on the diet, going on the low-fat diet, and not going on the low-fat diet. And we have a 95% confidence interval that that difference is between 0.7 and 3.12 pounds, which tells us that we have a 95% confidence interval that you're definitely going to lose some weight. We're not 100% sure, but we're confident that there's a 95% probability of that.