Editing Political polarization (section)

===Elite polarization===

[[File:NOMINATE polarization.jpg|thumb|Political polarization in the United States House of Representatives (DW-Nominate scores){{Update needed|date=July 2024}}]]
Elite polarization refers to polarization between the party-in-government and the party-in-opposition.<ref name=baldassarri-08/> Polarized political parties are internally cohesive, unified, programmatic, and ideologically distinct; they are typically found in a [[parliamentary system]] of democratic governance.<ref name="mann-12">{{cite book|url=https://books.google.com/books?id=CQORs1_S2sgC|title=It's Even Worse Than It Looks: How the American constitutional system collided with the new politics of extremism|last=Mann|first=Thomas E.|author2=Ornstein, Norman J.|publisher=[[Basic Books]]|year=2012|isbn=978-0465031337|archive-url=https://web.archive.org/web/20140705154533/http://books.google.com/books?id=CQORs1_S2sgC&printsec=frontcover|archive-date=2014-07-05|url-status=dead}}</ref><ref name=mccarty-06/><ref name=layman-06/><ref name=carmines-12/>

In a [[two-party system]], a polarized [[legislature]] has two important characteristics: first, there is little-to-no ideological overlap between members of the two parties; and second, almost all conflict over legislation and policies is split across a broad ideological divide. This leads to a conflation of political parties and ideologies (i.e., Democrat and Republican become nearly perfect synonyms for liberal and conservative) and the collapse of an ideological center.<ref name="mann-12" /><ref name="mccarty-06" /><ref name="layman-06" /><ref name="carmines-12" /> However, using a cross-national design that covers 25 European countries, a recent study shows that it is not the number of parties itself, but the way a party interreacts with another that influences the magnitude and nature of affective polarization.<ref name="doi.org">{{Cite journal |last1=Hahm |first1=Hyeonho |last2=Hilpert |first2=David |last3=König |first3=Thomas |date=2022-11-07 |title=Divided by Europe: affective polarisation in the context of European elections |url=https://doi.org/10.1080/01402382.2022.2133277 |journal=West European Politics |volume=46 |issue=4 |pages=705–731 |doi=10.1080/01402382.2022.2133277 |s2cid=253432411 |issn=0140-2382}}</ref>

The vast majority of studies on elite polarization focus on legislative and deliberative bodies. For many years, political scientists measured polarization in the US by examining the ratings of party members published by interest groups, but now, most analyze [[recorded vote|roll-call voting]] patterns to investigate trends in party-line voting and party unity.<ref name="fiorina-08" /><ref name="mccarty-06" /> Gentzkow, Shapiro, and Taddy used the text of the Congressional Record to document differences in speech patterns between Republicans and Democrats as a measure of polarization, finding a dramatic increase in polarized speech patterns starting in 1994.<ref>Gentzkow, Matthew, and Shapiro, Jesse, and Taddy, Matt [https://web.stanford.edu/~gentzkow/research/politext.pdf Measuring Polarization in High-Dimensional Data: Method and Application to Congressional Speech]"</ref>