Calling it a "mysterious algorithm," Amanda WestBook delves into the one about how higher click-through rates solely contribute to better quality scores, which isn't true. She explains the way tightly themed groups of keywords work, what "crappy quality score keywords" can do to a Web site, and how the landing page relies on the site's load time. That in turn leads to a better score, among other things. A related post details how higher positions in the search engine ranking influence quality scores, what happens when ads or keywords are paused, and why quality scores matter.