Most illuminating is how this documented chilling effect can be used, "Penney’s work may provide fodder for technology companies and others arguing for greater

Most illuminating is how this documented chilling effect can be used, "Penney’s work may provide fodder for technology companies and others arguing for greater restraint and disclosure about intelligence-gathering. Chilling effects are notoriously difficult to document and so have limited impact on laws and court rulings. More immediately, the research could aid a lawsuit filed by the American Civil Liberties Union on behalf of Wikipedia’s nonprofit parent organization and other groups against the NSA and the Justice Department." A study over a long period of time on many articles helps avoid the noise of news.