Should Viewability statistics be provided in Paid Search?
With Google recently moving the right hand side ads to the bottom of the page, many advertisers are concerned that their ads’ performance will drop, especially if the prices for the ads at the top of the page are inaccessibly expensive for their budget.
Forward3D's head of paid search, Tom Manning.
By bringing the new search results layout in line with what users have seen on mobile since 2011, Google has implemented a layout that is longer than it is wide, the opposite of typical desktop screens. As a result, any ads at the bottom of the page are now going to be below the fold. This means that these ads at the bottom could be gathering impressions without ever being seen if the user either doesn’t scroll down or chooses to click on one of the top ads or the natural search results. In theory, this will inevitably mean lower click through rates for bottom of the page ads, as they can’t be clicked on without being seen, but they will still gather impressions.
Although our data seems to suggest that bottom of the page ads do not suffer a lower click through rate compared to the side ads, there must still be a large number of impressions gathered when the ads are never actually seen by users in comparison to the side ads. This means that bottom of the page ads may actually have a much higher click through rate than their data shows.
As a result, I propose that Google should define whether users actually scrolled to the bottom of the page or not, and split impressions into two categories; ‘viewed impressions’ and ‘non-viewed impressions’. This echoes data available for display campaigns where viewable and non-viewable impressions are already treated very seriously.
This would allow users to calculate their actual click through rate for ads, using viewed impressions only, rather than making changes to ads based on potentially misleading data, e.g. an ad at the bottom may appear to have a low click through rate because users clicking on something else before they even see the ad, rather than there being a fundamental issue with the ad itself. Provided with this information, users could also see how much potential traffic they are missing by appearing at the bottom of the page rather than the top, providing useful information on which to base bid changes. I believe this would, in turn, actually benefit Google too if users were to increase their bids and attempt to reach the top positions, thereby creating more competition.
In Display a lot of pressure is put on publishers around viewable impressions because their inventory is charged on an impression basis and advertisers (understably) do not want to pay for non-viewed impressions. However, because Google’s paid search system charges for a click, there is actually no drawback in showing how many impressions are viewed or not as it does not affect what an advertiser pays for.
Forward3D have conducted a full analysis of the impact that the change in ad structure has had across its accounts, which can be downloaded for free here.
Tom Manning is head of paid media at Forward3D.