Media bias in presidential elections: a meta-analysis

A meta-analysis considered 59 quantitative studies containing data concerned with partisan media bias in presidential election campaigns since 1948. Types of bias considered were gatekeeping bias, which is the preference for selecting stories from one party or the other; coverage bias, which considers the relative amounts of coverage each party receives; and statement bias, which focuses on the favorability of coverage toward one party or the other. On the whole, no significant biases were found for the newspaper industry. Biases in newsmagazines were virtually zero as well. However, meta-analysis of studies of television network news showed small, measurable, but probably insubstantial coverage and statement biases.