eBay has been one of the largest advertisers on Google, but that might not be the case for much longer. It decided to do an A-B split test to determine how many of those clicks they would have eventually seen even without those paid placements; even going so far as to go dark in 30 market areas to provide a control. In a study conducted with eBay Labs along including fancy degree holders from Berkeley and U. Chicago, it showed that it only made back about 25 cents on the dollar spent.
The study shows that brand ads – and by that they mean ads that focus on the brand names of the products to be theoretically purchased, rather than “branding” ads – can be efficiently effective for potential new users to the retailer, but tend to be unnecessary for those who are already familiar with the retailer. eBay, more than most, would suffer from a high familiarity ratio, thus making its relative efficiency low.
One thing the full version of the study appears to miss, however, is that very high clickthrough rate experienced by an ad due to a specific brand reference that is common to the search term may have another financial benefit to the advertiser: increasing the “quality score” of the ad campaign, and thus reducing the expense of other clicks in the campaign.
eBay bids on a universe of more than 170 million keywords. It spends more than $50 million a year on online advertising.