News Reporting of Opinion Polls: Journalism and Statistical Noise

Polls play a key part in news media coverage of politics and election campaigns ( Benoit, Stein, & Hansen, 2005 ; Strömbäck & Dimitrova, 2006 ; Strömbäck & Shehata, 2007 ). This media focus on the “ horse race ” of politics is not a new phenomenon (e.g., Lazarsfeld, 1944 , p. 323; McCombs and Shaw, 1972 , pp. 179–180), but polls on voting intentions have steadily become more prevalent in the news, and they now constitute a ubiquitous part of election campaign coverage ( Strömbäck, 2012 ). Given the prominent role played by polls, it is not surprising that they have been studied quite extensively, often as indicators of the media’s tendency to frame politics as a strategic game ( Aalberg, Strömbäck, & de Vreese, 2012 ). A substantial amount of literature has focused on the causes behind the extensive poll coverage (e.g., Crespi, 1980 ; Frankovic, 2005 ; Matthews, Pickup, & Cutler, 2012 ; Rosenstiel, 2005 ; Strömbäck, 2009 ), whereas an even larger body of literature has focused on the effects of polls and strategic framing in general (e.g., Adriaansen, van Praag, & de Vreese, 2010 ; Cappella & Jamieson, 1997 ; de Vreese, 2004 , 2005 ; de Vreese & Semetko, 2002a ; Hahn & Iyengar, 2002 ; Moy & Rinke, 2012 ; Pedersen, 2012 ). While the causes and consequences of poll reporting have been studied comprehensively, less systematic work has been conducted on how the media report on polls ( Matthews, Pickup, & Cutler, 2012 ). However, poll coverage may have substantial political impact, not least on voters ( Moy & Rinke, 2012 ). Therefore, some studies have investigated the quality of such coverage, primarily by studying whether it includes explicit methodological information, for example, about statistical uncertainty ( Andersen, 2000 ; Brettschneider, 2008 ; Gahner Larsen & Straubinger, 2012 ; Hardmeier, 1999 ; Miller & Hurd, 1982 ; Sonck & Loosveldt, 2008 ; Welch, 2002 ).