C-Rank and D.I.A. are the main algorithms Naver uses to decide blog search results. C-Rank looks at the trustworthiness of the source (the blog), and D.I.A. at the quality of the document itself.
C-Rank evaluates a source's trustworthiness based on whether the blog has covered one topic consistently and in depth, and how much it is read and linked by other users. D.I.A. (Deep Intent Analysis) evaluates how well the experience and information in a post match the search intent.
In practice, a blog that narrows its topic and posts consistently, with concrete first-hand information in each post, fits both algorithms.
