Variance tells us how spread out the ages are in each racial group of people killed by police. If everyone were the same age, variance would be zero because there’s no spread. But in real life, ages vary, so we get a number that tells us how much they differ from the average age. For different racial groups have different variances in ages. This is important because when we use methods like ANOVA (Analysis of Variance), we assume that these variances are roughly the same across groups. But that’s not the case here, which means we might need to use different statistical methods that don’t make this assumption to accurately understand the data.