When Millward Brown tested 30 targeted TV commercials before an audience of African-American consumers in 2010, we found that 90% of the ads that featured black casting and cultural elements that blacks could relate to performed above average. But 85% of the commercials with no cultural elements other than black casting fell below that average.
The issue of casting among Hispanic consumers is trickier because Latinos can be of any race, and it is hard to determine (without falling into stereotypes) whether casting is Hispanic or not. In most cases, the only way one can be sure is if an ad is in Spanish. But when it comes to language, research shows that in-culture communication, depicting familiar situations, is more relevant to Hispanics than just hearing an advertisement in Spanish.
Read the entire article at Ad Age.