Various techniques are disclosed for facilitating on-line contextual analysis and/or advertising operations implemented in a computer network. According to some embodiments, various aspects may be used for enabling advertisers to provide contextual advertising promotions to end-users based upon real-time analysis of web page content which may be served to an end-user's computer system. In at least one embodiment, the information obtained from the real-time analysis may be used to select, in real-time, contextually relevant information, advertisements, and/or other content which may then be displayed to the end-user, for example, via real-time insertion of textual markup objects and/or dynamic content. According to specific embodiments, various operations may be performed for adapting or modifying a conventional context-based advertising systems to improve various features such as, for example, ad relevance estimation, click-through rate estimation, advertisement selection and layout, balancing exploration and exploitation, etc.