Propaganda, USAltntveMedia, USMnstrmMedia

Measuring the Power of US Main Stream Media

Professor Andrea Prat of Columbia University has just published a fascinating paper on Vox about a new, and in my opinion much more effective, way of measuring the potential power of a particular corporate media source. —

How can we measure media power?

I quote from his paper –emphasis mine

Andrea Prat, 22 August 2014


The media index measures the potential for a given media company to shift vote shares from one political party to another.

To measure this maximum potential, we answer the question, “assuming that the only goal of a media owner were to favour one political party, and that media users took the information they receive at face value, how much could the media owner influence voting behaviour?” The answer to this question identifies an upper bound to the power of a media company. It provides a basis for prudential regulation by directing attention to the highest damage potential of any media ownership pattern.

The media power index values for all major US news organisations in 2012 are shown in Figure 1. For media conglomerates the index includes all owned news sources on any platform. For instance, in 2012 News Corp owned both Fox and the Wall Street Journal. The index also covers multiple distribution channels for the same source. For instance, the New York Times entry includes both print readers and online readers.

Power index, 15 major US media companies, based on the 2012 Pew Institute Media Consumption Survey

Figure 1. Power index, 15 major US media companies, based on the 2012 Pew Institute Media Consumption Survey

The 22% index value for News Corp means that within this model and based on data available their owner could potentially turn a an electoral defeat with a 22% vote margin into an electoral victory. Namely, suppose that under neutral reporting party A would win with 61% of the votes and party B would lose with 39% of the votes. News Corp could shift 11% of the votes, thus guaranteeing that party B wins with 50% of the votes plus one. Of course, this is an upper bound to potential influence. It does not imply that News Corp will actually be able or willing to shift 11% of the votes. It just says that there is a set of conservative assumptions that lead to that figure.

Crucially for media regulation, these large power estimates are in marked contrast with the low market concentration of most media platforms in the US as gauged according to standard measures (see Noam 2009). It is true that media markets appear relatively fragmented, but this is not the right level of analysis for media plurality. Most American voters receive their news from a very small number of news sources. This creates the potential for the large political influence that this index captures.”