Meta is acting on its vow to reduce ad discrimination through technology. The company is rolling out a Variance Reduction System (VRS) in the US that ensures the real audience for an ad more closely matches the eligible target audience — that is, it shouldn't skew unfairly toward certain cultural groups. Once enough people have seen an ad, a machine learning system compares the aggregate demographics of viewers with those the marketers intended to reach. It then tweaks the ad's auction...