A nice article (linked below), is well worth reading.
< Research shows that online advertising is effective even at low CTR.
Indeed, comScore maintains that the primary value of online ads is the exposure itself and not necessarily the act of clicking.
In a study titled "How Online Advertising Works: Whither The Click?" comScore has shown that two-thirds of internet users do not click on any display ads over the course of a month and only 16 percent of internet users account for 80 percent of all clicks. Furthermore, clickers tend to be younger and less affluent than non-clickers. The comScore research confirmed that there is latency effect and branding value to online advertising, driving users to the advertiser's website even without clicking. >
< The research by comScore also indicates that display advertising has an effect on user behavior even at low CTR.
In the research, which included 139 display campaigns from seven verticals, comScore recorded substantial effects on traffic, sales and branding despite low CTR. The campaigns yielded a 46 percent lift in advertiser website visits over a four week period.
During the same period, exposed users were 38 percent more likely to conduct an advertiser-related branded-keyword search, and 27 percent more likely to make a purchase online.
Furthermore, exposed users were 17 percent more likely to make a purchase at the advertiser's retail store.>
< Search and display overlap
Our search-display overlap research revealed that one of every five users that arrived at an advertiser's site was exposed to a display ad.
Measuring search activity can be a good way to assess if a display campaign is performing.
For example, if users are searching for the tagline from your campaign, product name, or other branded keyword, you can be confident those terms are resonating with users. If there is no increase in branded keyword searches during the campaign, it may be time to revisit your ads. >
iMedia Connection:5 display advertising metrics you should know