If celebrities are brands, and brands aspire to be celebrated by consumers, having the wrong celebrity endorse the wrong brand can be pretty detrimental.

To help put some science behind the practice of matching brands and celebrities, Millward Brown has developed a new way to match celebrity and brand equity.

"It helps minimize the risk that goes into celebrity partnerships," Ann Green, senior vice president of marketing solutions for Millward Brown, tells Marketing Daily. "Celebrity partnerships require significant investment."

The offering integrates consumer ratings of Familiarity (how much one knows about a celebrity or brand), Affinity (how strongly one likes or dislikes a celebrity or brand) and Buzz (how much cache a celebrity or brand has) to develop a Cebra (celebrity + brand) score.

Not all Cebra scores are the same. According to a survey of 2,000 U.S. adults ages 18-64, teen star Miley Cyrus had a score of 61, which is the same as William Shatner. However, the matching practice shows that Cyrus is a good fit for L'Oreal or Starbucks, while Shatner (who is already a spokesman for Priceline.com) matched well with GEICO and Dell.

"We were surprised by the fact that Miley Cyrus and William Shatner -- two very different celebrities at the opposite end of the age spectrum -- had the same scores," Green says. "We [also] found some major stars scored lower than you would think simply because they weren't as high on likeability or affinity: stars like Oprah, Angelina Jolie and even Justin Timberlake. They are well-known around the world and generate a lot of buzz but don't garner as much of an emotional connection."

Matching the right celeb with the right brand can be important, particularly when it comes to attracting Millennials. According to a new study from Mediaedge:cia, 30% of 18- to-34-year-olds said they would try a product promoted by an admired celebrity, compared with 14% of 35 to-54-year-olds and 11% of people over age 55.

And while 35% of respondents to the survey believe celebrity endorsements improve a brand's awareness, help define its personality and generate interest, more than half of them (53%) also said they have trouble remembering which celebrities are endorsing which brand.

"Although 25% of all adults have had their purchase influenced --either positively or negatively -- by celebrity endorsers, advertisers have to be selective in their choice of celebrities," said Fran Kennish, Strategic Planning Director for Mediaedge:cia, in a statement. "A careful match of the celebrity personality, the category and the brand they represent, and the consumer can magnify the value and the effectiveness of celebrities as a communication vehicle."

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