Celebrity endorsements in advertising: All that glitters is not gold.

David Duchovny - Baume & Mercier Celebrity EndorsementWe love our celebrities, don’t we?

Christina Applegate takes motherhood … to celebrity status.

Zsa Zsa Gabor is a fabulous celebrity … and a panel of experts has been commissioned to find out why.

 His very existence … makes Prince William a celebrity.

Because the public goes so (Lady) gaga over celebrities, celebs have been used to hawk products and services for decades. Often, they can add pizzazz to what is otherwise a pretty routine advertising campaign. But how effective are the added glitz and glamour in ringing up additional sales?

I’ve long suspected that the value of celebrity endorsements might be over-hyped. Now we have some quantifiable proof. Ace Metrix, a California-based ad measurement firm, evaluated ~2,600 television ads shown during 2010. The company tested 263 unique national ads featuring celebrity endorsements, spanning 16 industries and 110 separate brands. All ads were tested within 48 hours of breaking nationally in order to capture immediate rather than “cultivated” ad effectiveness.

The celebrity ads were then evaluated against a control group of non-celeb ads in order to determine their comparative effectiveness in generating ad “lift” (better performance).

What the Ad Metrix analysis found was that only ~12% of the ads using celebrities showed more than 10% lift over average advertising norms in their respective industries. Even more startling, ~20% of the celebrity ads yielded 10% or worse (net negative) performance over the average advertising norms.

Here are some of the celebrities who had a “net negative” effect on their clients’ TV advertising effectiveness during 2010 – worst listed first:

Tiger Woods (Nike) – I guess this hardly comes as a surprise!
Lance Armstrong (Radio Shack)
Kenny Mayne (Gillette)
Dale Earnhardt, Jr. (Nationwide Auto Insurance)
Donald Trump (Macy’s)

Which celebrities managed to generate better-than-average scores? Queen of the heap is Oprah Winfrey for her 2010 spots for Liberty Mutual and Progressive Insurance. Ed Burns (iShares) and Carl Weathers (Bud Light) took the other top honors in positive lift.

Peter Daboll, head of Ace Metrix, had this to say about the findings: “This research proves unequivocally that, contrary to popular belief, the investment in a celebrity in TV advertising is rarely worthwhile. It is the advertising message that creates the connection to the viewer in areas such as relevance, information and attention, and this remains the most important driver of ad effectiveness.”

Interestingly, Oprah’s ads weren’t pitching products per se, but rather addressing current issue topics – in this case, warning against texting while driving. So one way to get through to the consumer via a celebrity is if the content is informational rather than a sales pitch.

But if the goal of the advertising is product sales, chances are the more the celebrity is truly “connected” to an advertiser’s product or service, the more successful he or she will be in engaging the target audience beyond simply the “curiosity factor.”

You can read detailed findings from the Ace Metrix analysis here.