Turn on the television or sign in to social media during election season and chances are you'll see plenty of negative campaigning. For decades, conventional wisdom has held that Americans hate negativity in political advertising, and some have even argued that its pervasiveness in recent seasons has helped to drive down voter turnout. Arguing against this commonly held view, Kyle Mattes and David P. Redlawsk show not only that some negativity is accepted by voters as part of the political process, but that negative advertising is necessary to convey valuable information that would not...