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network was larger with more sharing between members than the Republican
network.
These results should be interpreted with care. First, we should note that
the extended parties we identify in this study are not exclusive. There are many
other organizations that informed observers might categorize as affiliated with a
political party (e.g. National Rifle Association—Republicans; MoveOn.Org—
Democrats) that do not appear in our dataset. This is likely due to our
measurement of name exchanges, which groups will not participate in if they do
not solicit small donors or new members from the general population. Second,
the links we find between specific organizations and the Democratic or
Republican parties are often indirect. We should not be hasty to label as
“partisan” specific organizations with a low number of indirect ties to parties.
However, we do have more confidence the general pattern of polarization that
emerges from these indirect relationships is valid and noteworthy.
Finally, as with any exploratory work, additional research is required to
validate and extend this project. It would be helpful, for example, to vary the size
of initial donations or location of mailing addresses, to change the initial sample
for a snowball study, or to utilize a large scale one-time survey. We hope that
our effort sparks additional investigation of extended party networks.
Convention