Can’t say for sure without reading Green et al (edit: which I’ll now do; thanks, Gwern!), but they’re probably being run yearly. Assuming independence, a 3% year-on-year chance of changing parties gives roughly 20 years of stable party identification on average and 20% of all people sticking with the same party lifelong, which seems reasonable (though it’s less than I was expecting).
In actuality, of course, these numbers aren’t independent and a substantial portion of that variance is going to come from large-scale political events like the Southern shift you mentioned. That implies more stability in the absence of those shifts, though I don’t think we have enough information to say how common lifelong party identification is. Intuitively I’d expect a lot more than 20%.
A complicating factor is that political parties change, too. There is allegiance to a political party and there is allegiance to certain political ideology—and over time (e.g. a couple of decades) you can get a serious divergence.
they’re probably being run yearly
That may make more sense—I assumed (without a good reason) a much longer time horizon.
There is allegiance to a political party and there is allegiance to certain political ideology—and over time (e.g. a couple of decades) you can get a serious divergence.
I wouldn’t expect that to matter much. Political parties being made of people, I’d expect their ideological alignments to shift no more quickly than their constituents’; weird network effects might override this under certain circumstances, but in the context of US politics this historically doesn’t seem to happen very much. (Even the Southern shift was almost exclusively about emphasis on civil rights; both parties’ economic policies and broader ideologies remained more or less stable.)
Political parties being made of people, I’d expect their ideological alignments to shift no more quickly than their constituents’;
Political parties are also often made of factions. The outcomes of their power struggles might significantly change the party’s character.
In general, I suspect we need to be clear about when we are speaking about human universals and when we are speaking about politics in a given country. The US political parties are not the same as, say, the European political parties and I would expect the political behaviour (e.g. party loyalty) to be noticeably different between the continents.
In particular, under a two-party system the opportunities for changing party allegiance look to me much more limited compared to under a multi-party system.
Can’t say for sure without reading Green et al (edit: which I’ll now do; thanks, Gwern!), but they’re probably being run yearly. Assuming independence, a 3% year-on-year chance of changing parties gives roughly 20 years of stable party identification on average and 20% of all people sticking with the same party lifelong, which seems reasonable (though it’s less than I was expecting).
In actuality, of course, these numbers aren’t independent and a substantial portion of that variance is going to come from large-scale political events like the Southern shift you mentioned. That implies more stability in the absence of those shifts, though I don’t think we have enough information to say how common lifelong party identification is. Intuitively I’d expect a lot more than 20%.
A complicating factor is that political parties change, too. There is allegiance to a political party and there is allegiance to certain political ideology—and over time (e.g. a couple of decades) you can get a serious divergence.
That may make more sense—I assumed (without a good reason) a much longer time horizon.
So: politics is not about policy. But we already knew that...
Politics is complicated and multifaceted and diverse. It is about identity, and about policy, and about power, and about money, etc. etc.
I wouldn’t expect that to matter much. Political parties being made of people, I’d expect their ideological alignments to shift no more quickly than their constituents’; weird network effects might override this under certain circumstances, but in the context of US politics this historically doesn’t seem to happen very much. (Even the Southern shift was almost exclusively about emphasis on civil rights; both parties’ economic policies and broader ideologies remained more or less stable.)
Political parties are also often made of factions. The outcomes of their power struggles might significantly change the party’s character.
In general, I suspect we need to be clear about when we are speaking about human universals and when we are speaking about politics in a given country. The US political parties are not the same as, say, the European political parties and I would expect the political behaviour (e.g. party loyalty) to be noticeably different between the continents.
In particular, under a two-party system the opportunities for changing party allegiance look to me much more limited compared to under a multi-party system.