The expansion of radio and television talk shows has given candidates access to more free airtime. An appearance by a presidential contender assures such programs instant ratings, and it gives candidates an opportunity to speak directly to the American people without having their statements analyzed by broadcast journalists. A similar advantage is gained from the so-called infomercial, in which candidates buy a half-hour block of time to explain their positions, although the costs are significant. H. Ross Perot used both of these longer formats quite successfully in the 1992 campaign.