Doctoral Candidate at
News Ties: A Study of Media-Level
Agenda-Setting
Self-Commentary
The
research presented here proposes an exploration of inter-media agenda-setting.
One of the big questions in the field is whether proliferation of channels and
information overload have fragmented news content, rendering the idea of a
consistent mainstream media agenda obsolete. The study employs network analysis
methods to test this proposition. News outlets are seen as a set of
interconnected nodes with ties based on overlap of issue coverage. Two news
sources are linked if there is an above average similarity in their selection
of topics over a period of time. The research demonstrates that mainstream
media outlets not only have overlapping agendas at a given point in time, but
also exhibit patterns of shared coverage that persist over time. A QAP analysis
comparing networks of shared topics compiled for January and December of 2007
shows a strong and significant correlation (r=0.87, p<0.001) between the
two. Furthermore, both networks are dense, well-connected and have a relatively
high centralization index - something that goes against the idea of
fragmentation and disintegration of media agenda.
The study goes on to explore the set of properties that are likely to influence the overlap of media agendas. Factors taken into consideration include format (newspaper, radio, network TV, cable TV, Internet), common ownership, and volume of the outlet production. An ERG model including parameters for those factors as well as basic structural signatures is fitted to the December 2007 news outlet network. Results of the estimation indicate that both production volume and common ownership affect the topic overlap of news outlets. In order to investigate the patterns of shared coverage within and across media sectors, a blockmodel analysis is performed (results presented on the figure above). Network TV, Internet and radio outlets are likely to produce coverage similar to that of other media of the same type. This does not hold true for newspapers and cable TV. The Network TV outlets have dense ties with all of the other four sectors – a finding consistent with previous research on the influence of television news.
PEER REVIEW COMMENT
No. 1
This submission shows the topic similarity between news outlets, where a tie exists if two organizations cover a similar array of topics. The pairing of the block-model results and the detail graph is very helpful, as the detailed layout is so dense as to make identifying positions challenging. I wonder if the image would be improved by forcing the nodes into a positioning more similar to the block layout or somehow incorporating a weighting that differentiates within and between-block ties?
PEER REVIEW COMMENT
No. 2
The visualization uses a block-modeling approach to show that despite a proliferation of media outlets, there is much convergence on news topics. While the block model image portrays a general sense of the interconnectedness of the media system, the network image itself is somewhat swamped by density of ties, with little information aside from the size and centrality of the media outlet evident from the detailed image. The rendering itself is nicely done, with a color scheme that is easy to view and differentiate.
PEER REVIEW COMMENT
No. 3
This
visualization has excellent theoretical framing, providing an interesting
question, and an easily understood visual answer. The blockmodel and adjacency plots compliment
each other well, and give us both a sense of connectedness and structure. The use of loops in the blockmodel is
especially effective at giving us a sense of internal connectedness compared to
connectedness between. I'd be interested
to see a hybrid of the blockmodel and adjacency views.