Red-Blue Roundtable: Valdis Krebs
For a social network scientist, Amazon is a great sandbox for experimenting and searching for interesting patterns!
I started mapping book networks in the last century. It was 1998 when an on-line conversation raised my curiosity. Here is the original white paper I wrote about that initial investigation.
After the late Tim Russert brought us the "red states – blue states" meme during the 2000 election I started to investigate patterns of political books. I tried various data collection techniques and found an interesting outcome –- no matter how I collected the data I ended up with highly similar patterns. I use snowball sampling -- start at a known point and follow the data out 1 or 2 steps. Once the snowball sample is complete, I start to eliminate the noise in the network -– I want to find the strong patterns that multiple overlapping networks provide. When the patterns emerge I usually see two strong clusters, with a minor cluster or scattering of books between the two large components. I only color the components after my network analysis software finds the emergent groups in the data –- then it is obvious which cluster is blue and which is red.
Below is the first political book map I published on my web site. It showed the famous red-blue divide that had become common wisdom by 2003. It was ironic, and a commentary on our situation, that the center book -– holding both sides together -– was titled: What Went Wrong!
The sharp left-right divide remained in place for the 2004 US presidential election. Below are two graphs of the same data. The first graph is the emergent cluster view –- those similarly connected are closer together. This map was done about 1 year after the 2003 map above. They both contain many different books, yet reveal a very similar pattern and a strong divide.
The second view is of the very same data as above. This view was made after the emergent view showed us who was in which cluster. This view accentuates the divide by putting each side into facing arcs and then sorting the books alphabetically for easy reference. As in the diagram above most links are within the cluster with no direct links between clusters, only through 3 intermediary books that ended up spanning the boundary between red and blue.
During the 2008 US presidential election we expected a different pattern to appear. After all both candidates were initially talking of bridging the divide and the 2006 mid-term elections showed us several examples where the strong boundaries were becoming more fuzzy. The blues and the intermediates [often books outside of 2-party mainstream thinking] started to overlap. Ron Paul, Jesse Ventura, and Lou Dobbs were finding more blue readers than red readers.
The map below was done just before the two major party conventions in 2008. We again see: different books, same pattern. We also now see [based on on current snowball sampling scheme] that the left reads a greater number of books than the right. This map does not indicate volume or quantity of sales. It is very possible that the right buys more books of a more focused set. As a general rule we do not compare quantities of books sold, we just use it a bar to include/exclude books in our starting sample -– a top % of Amazon’s bestsellers are chosen as our starting point. Our maps reflect patterns found in the bestsellers on Amazon –- we do not know what is happening amongst low volume books. Our maps capture the most common patterns.
As we have witnessed, after both national conventions this summer,
there is still a strong and vocal divide between red and blue. The war
of words and accusations grows louder as election day draws nearer.
Arms merchants do well in times of war –- no matter if the ammunition
are bullets or words! --Valdis Krebs
See the whole Red-Blue Roundtable