• by Laurie Sullivan  @lauriesullivan, July 7, 2015

Ebay.com is the most visible Web site in Google Shopping image-based product listing ads (PLAs), and Amazon is the most visible in Google AdWords text-based paid search advertising, according to data released Tuesday. 

Findings from Searchmetrics' analysis, detailed in the white paper Google Shopping & AdWords: The 10 Most Important Players, analyzed the search results for millions of keywords throughout 2014 to rank the top ten Web sites displayed in the two Google ad formats. The rankings were drawn up according to a PLA Visibility score and a PPC Visibility score, which are a measure of how frequently and prominently the sites’ ads appear within search results. 

Ebay.com took the top spot in the ranking of top sites in Google Shopping PLAs with a visibility score of 7,591,817.  Walmart.com and rakuten.com followed with 6,198,399 and 2,289,424; respectively, with Macy's and Etsy rounding out the top five.

Interestingly, the top five most visible sites in AdWords paid-search advertising were Amazon with 9,381,597; wow.com at 6,577,132; ask.com with 6,366,023; webcrawler.com with 3,013,297; and about.com at 1,769,772.

Among retailers, Target came in at No. 7 in the ranking of the most visible Web sites in AdWords paid-search advertising with 1,430,896; zappos.com at No. 9, with 1,387,534; and bestbuy.com at No. 10 with 1,289,807.

Searchmetrics' studies show that PLAs have a slightly higher click-through rate than AdWords ads for shopping related searches, but also cost slightly more with a higher cost-per-click. PLAs are more expensive, but typically yield better results than AdWords.

Marcus Tober, Searchmetrics’ founder and CTO, explains in the white paper that in the second quarter of 2014, the average click-through rate for PLAs was 5.91%, whereas AdWords ads had a CTR of 4.91%. The differences are reflected in prices. The average advertising costs for a PLA click was $1.63, and the CPC for a text ad for product-related searches was $1.07.

Searchmetrics estimates the share of search engine results pages displaying PLAs has more than doubled in 2014 from 7.5% to 16% of all search results. With AdWords, the numbers remain constant. At the end of 2014, 63% of all search results included at least one AdWords ad, which is fairly constant for share of search results during the entire year.

Google served PLAs in significantly fewer search results in June and July 2014, compared with the rest of the year. The trend is the same for AdWords, according to Searchmetrics.