Rule based targeting, behavioural targeting, and contextual targeting are three different types of targeting methods, delivering customized ads based on different categories of variables. A rule based targeting method uses viewers’ own characteristics, while behavioural targeting delivers ads based on previous content users have browsed. At the same time, contextual targeting uses the characteristics of the webpage on which an ad will be displayed to decide which ads to display. On the other hand, all the three categories of factors and the interaction among them could impact the effectiveness of an online displaying ad. For organizations seeking to optimize their online marketing effort, it therefore becomes crucial to have a thorough understanding on how the variables from individual, behavioural, and contextual aspects moderate the effectiveness of a targeting method based on variables in other categories. But we have not yet found any study provides a theoretic framework to support such understanding. This paper thus proposes to investigate the moderation effect of variables in different categories on the effectiveness of a targeting method based on variables from other categories by using cookie-based data collected by an online marketing firm for its online displaying ads.