摘要:Thanks to its wide range of targeting, Internet has become a very attractive medium for advertisers. Although the current technologies can collect data about an individual's online activities and utilize it for a precise targeting, the traditional way of targeting based on affinity is still widely used. The goal of this paper is to evaluate the possibility of the traditional way of demographic targeting by gender and age on the Czech Internet thorough data mining of NetMonitor database. Research findings show that, in certain cases, traditional affinity-based ad targeting can be effective. This is especially true when targeting men and younger users. On the other hand, this method also generates wasted ad impressions outside the target group. This is particularly problematic when targeting elderly users. Modern techniques of ad targeting which are based on tracking users’ activities are likely to further expand.