Editing Political polarization (section)

==Causes==
There are various causes of political polarization and these include political parties, [[redistricting]], the public's [[political ideologies|political ideology]], the mass media, and political context.

===Party polarization===
Some scholars argue that diverging parties has been one of the major driving forces of polarization as policy platforms have become more distant. This theory is based on recent trends in the [[United States Congress]], where the [[majority party]] prioritizes the positions that are most aligned with its [[party platform]] and political ideology.<ref name="ura-12">{{cite journal|last=Ura|first=Joseph Daniel|author2=Ellis, Christopher R.|title=Partisan Moods: Polarization and the Dynamics of Mass Party Preferences|journal=The Journal of Politics|date=10 February 2012|volume=74|issue=1|pages=277–291|doi=10.1017/S0022381611001587|hdl=1969.1/178724|s2cid=55325200|hdl-access=free}}</ref> The adoption of more ideologically distinct positions by political parties can cause polarization among both elites and the electorate. For example, after the passage of the [[Voting Rights Act]], the number of conservative Democrats in Congress decreased, while the number of conservative Republicans increased. Within the electorate during the 1970s, [[Southern Democrats]] shifted toward the [[Republican Party (United States)|Republican Party]], showing polarization among both the elites and the electorate of both main parties.<ref name="mann-12" /><ref name="abramowitz-98">{{cite journal|last=Abramowitz|first=Alan I.|author2=Saunders, Kyle L.|title=Ideological Realignment in the U.S. Electorate|journal=The Journal of Politics|date=August 1998|volume=60|issue=3|page=634|doi=10.2307/2647642|jstor=2647642|s2cid=154980825}}</ref><ref name="galston-09">{{cite journal|last=Galston|first=William A.|title=Political Polarization and the U.S. Judiciary|journal=UKMC Law Review|year=2009|volume=77|issue=207|url=http://heinonline.org/HOL/Page?handle=hein.journals/umkc77&div=15&g_sent=1&collection=journals}}</ref> In this sense, political polarization could be a top-down process, in which elite polarization leads to—or at least precedes—popular polarization.<ref>{{cite book|last1=Benkler|first1=Yochai|url=https://www.oxfordscholarship.com/view/10.1093/oso/9780190923624.001.0001/oso-9780190923624-chapter-10|title=Network Propaganda: Manipulation, Disinformation, and Radicalization in American Politics|publisher=Oxford Scholarship Online|year=2018|publication-date=2018-10-01|doi=10.1093/oso/9780190923624.003.0010|isbn=978-0-19-092366-2}}</ref> However, polarization among elites does not necessarily produce polarization within the electorate, and polarized electoral choices can often reflect elite polarization rather than voters' preferences.<ref name="fiorina-08" /><ref name="mccarty-06" /><ref name="hetherington-09" /><ref name="carmines-12" /><ref name="claassen-08" />

Political scientists have shown politicians have an incentive to advance and support polarized positions.<ref name="beniers-07">{{cite journal|last=Beniers|first=Klaas J.|author2=Dur, Robert|title=Politicians' motivation, political culture, and electoral competition|journal=International Tax and Public Finance|date=1 February 2007|volume=14|issue=1|pages=29–54|doi=10.1007/s10797-006-8878-y|hdl=1765/6632 |s2cid=39796862|url=https://papers.tinbergen.nl/04065.pdf}}</ref> These argue that during the early 1990s, the Republican Party used polarizing tactics to become the majority party in the [[United States House of Representatives]]—which political scientists [[Thomas E. Mann]] and [[Norman Ornstein]] refer to as [[Newt Gingrich]]'s "guerrilla war."<ref name="mann-12" /> What political scientists have found is that moderates are less likely to run than are candidates who are in line with party doctrine, otherwise known as "party fit."<ref>{{cite journal|last1=Thomsen|first1=Danielle M.|title=Ideological Moderates Won't Run: How Party Fit Matters for Partisan Polarization in Congress|journal=The Journal of Politics|date=2014|volume=76|issue=3|pages=786–797|doi=10.1017/s0022381614000243|jstor=0022381614000243|hdl=10161/8931|s2cid=154980416|hdl-access=free}}</ref> Other theories state politicians who cater to more extreme groups within their party tend to be more successful, helping them stay in office while simultaneously pulling their constituency toward a polar extreme.<ref name="hirano-09">{{cite journal|last=Hirano|first=Shigeo Jr. |author2=James M. Snyder|author3=Michael M. Ting|title=Distributive Politics with Primaries|journal=Journal of Politics|year=2009|volume=71|issue=4|pages=1467–1480|url=http://www.yale.org/leitner/resources/docs/snyder.pdf|doi=10.1017/s0022381609990247|s2cid=11453544|access-date=2013-04-22|archive-date=2014-05-31|archive-url=https://web.archive.org/web/20140531104933/http://www.yale.org/leitner/resources/docs/snyder.pdf|url-status=dead}}</ref> A study by Nicholson (2012) found voters are more polarized by contentious statements from leaders of the opposing party than from the leaders of their own party. As a result, political leaders may be more likely to take polarized stances.<ref name="nicholson-12">{{cite journal|last=Nicholson|first=Stephen P.|title=Polarizing Cues|journal=American Journal of Political Science|date=1 January 2012|volume=56|issue=1|pages=52–66|doi=10.1111/j.1540-5907.2011.00541.x|pmid=22400143|s2cid=147497906 }}</ref>

With regards to [[multiparty systems]], [[Giovanni Sartori]] (1966, 1976) claims the splitting of ideologies in the public constituency causes further divides within the political parties of the countries. He theorizes that the extremism of public ideological movement is the basis for the creation of highly polarized multiparty systems. Sartori named this polarizing phenomenon [[polarized pluralism]] and claimed it would lead to further polarization in many opposing directions (as opposed to in simply two directions, as in a polarized two-party system) over policy issues.<ref name="sartori-66">{{cite journal|last=Sartori|first=Giovanni|title=European political parties: the case of polarized pluralism|journal=Political Parties and Political Development|pages=137–176|year=1966|doi=10.1515/9781400875337-006|isbn=978-1400875337}}</ref><ref name="sartori-76">{{cite book|last=Sartori|first=Giovanni|title=Parties and party systems : a framework for analysis|year=1976|publisher=ECPR|location=Colchester|isbn=978-0954796617|url=https://books.google.com/books?id=ywr0CcGDNHwC|edition=[Nouvelle édition]}}</ref><ref name="johnston-08">{{cite journal|last=Johnston|first=Richard|title=Polarized Pluralism in the Canadian Party System: Presidential Address to the Canadian Political Science Association, June 5, 2008|journal=Canadian Journal of Political Science|date=17 December 2008|volume=41|issue=4|page=815|doi=10.1017/S0008423908081110|s2cid=154599342}}</ref> Polarization in multiparty systems can also be defined along two ideological extremes, like in the case of [[India]] in the 1970s. Ideological splits within a number of India's major parties resulted in two polarized coalitions on the right and left, each consisting of multiple political parties.<ref name="davey-72">{{cite journal|last=Davey|first=Hampton|title=Polarization and Consensus in Indian Party Politics|journal=Asian Survey|date=1 August 1972|volume=12|issue=8|pages=701–716|doi=10.2307/2643110|jstor=2643110}}</ref>

Political fund-raisers and donors can also exert significant influence and control over legislators. Party leaders are expected to be productive fund-raisers, in order to support the party's campaigns. After ''[[Citizens United v. Federal Election Commission]]'', special interests in the U.S. were able to greatly impact elections through increased undisclosed spending, notably through [[Super PACs|Super political action committees]]. Some, such as ''[[The Washington Post|Washington Post]]'' opinion writer [[Robert G. Kaiser|Robert Kaiser]], argued this allowed wealthy people, corporations, unions, and other groups to push the parties' policy platforms toward ideological extremes, resulting in a state of greater polarization.<ref name="mann-12" /><ref name="kaiser-10">{{cite book|last=Kaiser|first=Robert G.|title=So damn much money : the triumph of lobbying and the corrosion of American government|year=2010|publisher=Vintage Books|location=New York|isbn=978-0307385888|url=https://books.google.com/books?id=AJxU1MzQZVoC|edition=1st Vintage Books}}</ref> Other scholars, such as Raymond J. La Raja and David L. Wiltse, note that this does not necessarily hold true for mass donors to political campaigns. These scholars argue a single donor who is polarized and contributes large sums to a campaign does not seem to usually drive a politician toward political extremes.<ref name="la-raja-11">{{cite journal|last=La Raja|first=R.J.|author2=Wiltse, D.L.|title=Don't Blame Donors for Ideological Polarization of Political Parties: Ideological Change and Stability Among Political Contributors, 1972–2008|journal=American Politics Research|date=13 December 2011|volume=40|issue=3|pages=501–530|doi=10.1177/1532673X11429845|s2cid=143588919}}</ref><ref name="tam-cho-07">{{cite journal|last=Tam Cho|first=Wendy K.|author2=Gimpel, James G.|title=Prospecting for (Campaign) Gold|journal=American Journal of Political Science|date=1 April 2007|volume=51|issue=2|pages=255–268|doi=10.1111/j.1540-5907.2007.00249.x|url=http://cho.pol.illinois.edu/wendy/papers/krige.pdf|access-date=22 April 2013|archive-date=3 April 2015|archive-url=https://web.archive.org/web/20150403154456/http://cho.pol.illinois.edu/wendy/papers/krige.pdf|url-status=dead}}</ref>

===The public===
In democracies and other [[Representative democracy|representative governments]], citizens vote for the political actors who will represent them. Some scholars argue that political polarization reflects the public's ideology and voting preferences.<ref name="galston-09" /><ref name="garner-10">{{cite journal | last1 = Garner | first1 = Andrew | last2 = Palmer | first2 = Harvey | title = Polarization and issue consistency over time | journal = [[Political Behavior (journal)|Political Behavior]] | volume = 33 | issue = 2 | pages = 225–246 | publisher = [[Springer Science+Business Media|Springer]] | doi = 10.1007/s11109-010-9136-7 | date = June 2011 | s2cid = 143137236 }}</ref><ref name="mason-12">{{cite journal|last=Mason|first=Lilliana |title=The rise of uncivil agreement: issue versus behavioral polarization in the American electorate|journal=[[American Behavioral Scientist]]|date=January 2013|volume=57|issue=1|pages=140–159 | publisher = [[SAGE Publications|SAGE]] |doi= 10.1177/0002764212463363 |s2cid=147084342 }}</ref><ref name="murakami-07">{{cite journal|last=Murakami|first=Michael H.|title=How party polarization affects candidate evaluations: the role of ideology|journal=Paper Presented at the Annual Meeting of the American Political Science Association, Hyatt Regency Chicago and the Sheraton Chicago Hotel and Towers, Chicago, Illinois|year=2007|url=http://citation.allacademic.com/meta/p_mla_apa_research_citation/2/1/0/3/3/pages210336/p210336-1.php|access-date=2013-04-22|archive-date=2015-04-03|archive-url=https://web.archive.org/web/20150403113327/http://citation.allacademic.com/meta/p_mla_apa_research_citation/2/1/0/3/3/pages210336/p210336-1.php|url-status=dead}}</ref> Dixit and Weibull (2007) claim that political polarization is a natural and regular phenomenon. Party loyalism is a strong element of voters' thinking. Individuals who have higher political knowledge will not be influenced by anything a politician says. The polarization is merely a reflection of the party that the voter belongs to, and whichever direction it moves in.<ref>{{cite journal |last1=Barber |first1=Michael |last2=Pope |first2=Jeremy C. |title=Does Party Trump Ideology? Disentangling Party and Ideology in America |journal=American Political Science Review |date=February 2019 |volume=113 |issue=1 |pages=38–54 |doi=10.1017/S0003055418000795|s2cid=150286388 }}</ref> They argue that there is a link between public differences in ideology and the polarization of representatives, but that an increase in preference differences is usually temporary and ultimately results in compromise.<ref name="dixit-07">{{cite journal|last1=Dixit|first1=Avinash K. | last2 = Weibull |first2= Jörgen W. |title=Political polarization|journal=[[Proceedings of the National Academy of Sciences of the United States of America|Proceedings of the National Academy of Sciences]]|date=1 May 2007|volume=104|issue=18 |pages=7351–7356 |doi=10.1073/pnas.0702071104 |pmid=17452633 |pmc=1863477 | jstor = 25427490 | publisher = [[National Academy of Sciences]] |bibcode=2007PNAS..104.7351D |doi-access=free }}</ref> Fernbach, Rogers, Fox and Sloman (2013) argue that it is a result of people having an exaggerated faith in their understanding of complex issues. Asking people to explain their policy preferences in detail typically resulted in more moderate views. Simply asking them to list the reasons for their preferences did not result in any such moderation.<ref>{{Citation
 | last1 =Fernbach
 | first1 =Phillip
 | last2 =Rogers
 | first2 =Todd
 | last3 =Fox
 | first3 =Craig
 | last4 =Sloman
 | first4 =Steven
 | title =Political Extremism Is Supported by an Illusion of Understanding
 | journal =Psychological Science
 | volume =24
 | issue =6
 | pages =939–946
 | date =25 April 2013
 | url =https://scholar.harvard.edu/files/todd_rogers/files/political_extremism.pdf
 | doi =10.1177/0956797612464058| pmid =23620547
 | s2cid =6173291
 }}</ref>

Studies undertaken in the U.S. (2019) and the UK (2022) have found that political polarization is generally less acute among the public than is portrayed in the media.<ref>{{cite web
 |url= https://perceptiongap.us/
 |title= The Perception Gap
 |work= More in Common
 |author= Stephen Hawkins, Daniel Yudkin, Tim Dixon
 |date =June 2019
|access-date= 11 May 2022
}}</ref><ref name ="InCommon">{{cite web
 |url= https://ourglobalfuture.com/reports/the-centre-holds/
 |title= The Centre holds
 |work= Global Future
 |author= Renie Anjeh, Isabel Doraisamy
 |date= April 2022
 |access-date= 11 May 2022
 |archive-date= 1 May 2022
 |archive-url= https://web.archive.org/web/20220501112852/https://ourglobalfuture.com/reports/the-centre-holds/
 |url-status= dead
 }}</ref> Moreover, non-nuanced reporting by the media about poll data and public opinions can even aggravate political polarization.<ref>{{Cite journal |last1=Willems |first1=Jurgen |last2=Meyfroodt |first2=Kenn |date=2024-01-30 |title=Debate: Reporting pre-election polls: it is less about average Jane and Joe, and more about polarized Karen and Kevin |url=https://www.tandfonline.com/doi/full/10.1080/09540962.2024.2306912 |journal=Public Money & Management |volume=44 |issue=3 |language=en |pages=185–186 |doi=10.1080/09540962.2024.2306912 |issn=0954-0962|hdl=1854/LU-01HNDE8TMQF8BFNFMTD2P3A21T |hdl-access=free }}</ref>

[[Morris P. Fiorina]] (2006, 2008) posits the hypothesis that polarization is a phenomenon which does not hold for the public, and instead is formulated by commentators to draw further division in government.<ref name="fiorina-08" /><ref name="fiorina-06">{{cite book|url=https://archive.org/details/culturewarmythof00fior|title=Culture War? The Myth of a Polarized America|last=Fiorina|first=Morris P.|author2=Samuel J. Abrams|author3=Jeremy C. Pope|publisher=[[Pearson Longman]]|year=2006|isbn=978-0321276407}}</ref><ref name="born-94">{{cite journal|last=Born|first=Richard|title=[Split-ticket voters, divided government, and Fiorina's policy-balancing model]: rejoinder|journal=[[Legislative Studies Quarterly]]|date=February 1994|volume=19 |issue=1 |pages=126–129| publisher = [[American Political Science Association]] |jstor=439804}}</ref> Fiorina connects this phenomenon to what he describes as "party sorting", which is where political ideologies tend to associate with specific political parties (conservatives with the Republican Party and liberals with the Democratic party).<ref>{{Cite web |last1=Fiorina |first1=Morris |last2=Mathew |first2=Levendusky |date=2006 |title=Disconnected: The political class versus the people. Red and Blue Nation: Characteristics, Causes, and Consequences of America's Polarized Politics |url=https://bpb-us-w2.wpmucdn.com/web.sas.upenn.edu/dist/9/244/files/2016/10/fl_brookings_volume-1aluxd6.pdf |access-date=12 March 2024}}</ref> Other studies indicate that cultural differences focusing on ideological movements and geographical polarization within the United States constituency is correlated with rises in overall political polarization between 1972 and 2004.<ref name="abramowitz-08" /><ref name="abramowitz-05">{{cite journal | url = http://www.dartmouth.edu/~govt/docs/Abramowitz.pdf | last1 = Abramowitz | first1 = Alan | last2 = Saunders | first2 = Kyle L. | title = Why can't we all just get along? The reality of polarized America | journal = The Forum | volume = 3 | issue = 2 | pages = 1–22 | publisher = [[Walter de Gruyter|De Gruyter]] | doi = 10.2202/1540-8884.1076 | date = July 2005 | s2cid = 145471342 | url-status = bot: unknown | archive-url = https://web.archive.org/web/20131019203620/http://www.dartmouth.edu/~govt/docs/Abramowitz.pdf | archive-date = 2013-10-19 }}</ref>

Religious, ethnic, and other cultural divides within the public have often influenced the emergence of polarization. According to Layman et al. (2005), the ideological split between U.S. Republicans and Democrats also crosses into the religious cultural divide. They claim that Democrats have generally become more [[moderate]] in religious views whereas Republicans have become more traditionalist. For example, political scientists have shown that in the United States, voters who identify as Republican are more likely to vote for a strongly [[evangelical]] candidate than Democratic voters.<ref name="campbell-11">{{cite journal|last1=Campbell|first1=David E.|last2 = Green | first2 = John C. | last3 = Layman | first3 = Geoffrey C. |title=The party faithful: partisan images, candidate religion, and the electoral impact of party identification|journal=[[American Journal of Political Science]]|date= January 2011|volume=55|issue=1|pages=42–58 |doi=10.1111/j.1540-5907.2010.00474.x | publisher = [[Wiley-Blackwell|Wiley]] |doi-access=free}}</ref> This correlates with the rise in polarization in the United States.<ref name="layman-05">{{cite journal|last1=Layman |first1= Geoffrey C. | last2 =Green | first2 = John C. |title=Wars and rumours of wars: the contexts of cultural conflict in American political behaviour|journal=[[British Journal of Political Science]]|date=January 2006|volume=36|issue=1 |pages=61–89 | publisher = [[Cambridge University Press|Cambridge Journals]] |doi=10.1017/S0007123406000044 | jstor = 4092316 |s2cid= 144870729 }}</ref> Another theory contends that religion does not contribute to full-group polarization, but rather, [[coalition]] and party activist polarization causes party shifts toward a political extreme.<ref name="brooks-04">{{cite journal|url=http://sociology.fas.nyu.edu/docs/IO/3858/A_Great_Divide.pdf|last=Brooks|first=Clem|author2=Manza, Jeff|title=A great divide? Religion and political change in U.S. national elections, 1972–2000|journal=[[The Sociological Quarterly]]|date=1 May 2004|volume=45|issue=3|pages=421–450|doi=10.1111/j.1533-8525.2004.tb02297.x|publisher=[[Wiley-Blackwell|Wiley]]|s2cid=1887424|access-date=22 April 2013|archive-url=https://web.archive.org/web/20100611202750/http://sociology.fas.nyu.edu/docs/IO/3858/A_Great_Divide.pdf|archive-date=11 June 2010|url-status=dead|df=dmy-all}}</ref>

In some post-colonial countries, the public may be polarized along ethnic divides that remain from the colonial regime.<ref name="bhavnani-08">{{cite journal|last1=Bhavnani|first1=Ravi | last2 =Miodownik | first2= Dan|title=Ethnic polarization, ethnic salience, and Civil War |journal=[[Journal of Conflict Resolution]] |date=February 2009 |volume=53 |issue=1 |pages=30–49 |doi=10.1177/0022002708325945 | publisher = [[SAGE Publications|SAGE]] |s2cid=145686111 }}</ref> In [[South Africa]] in the late 1980s, members of the conservative, pro-apartheid [[National Party (South Africa)|National Party]] were no longer supportive of [[apartheid]], and, therefore, no longer ideologically aligned with their party. Dutch [[Afrikaners]], white English, and native Africans split based on racial divisions, causing polarization along ethnic lines.<ref name="sisk-89">{{cite journal|last=Sisk|first=Timothy D.|title=White politics in South Africa: politics under pressure|journal=[[Africa Today]]|date=January 1989|volume=36|issue=1 |pages=29–39 | publisher = [[Indiana University Press]] |jstor=4186531}}</ref><ref name="darity-09">{{citation | url = http://www.cpc.unc.edu/research/publications/3710 | last = Darity | first = William A. | contribution = Economic theory and racial economic inequality | editor-last1 = Dodson | editor-first1 = Howard | editor-last2 = Palmer | editor-first2 = Colin A. | title = The Black condition | pages = 1–43 | publisher = Michigan State University Press | location = East Lansing, Michigan | year = 2009 | isbn = 978-0870138386 | postscript = . | access-date = 2016-02-12 | archive-date = 2017-05-10 | archive-url = https://web.archive.org/web/20170510105746/http://www.cpc.unc.edu/research/publications/3710 | url-status = dead }}</ref>

[[Economic inequality]] can also motivate the polarization of the public.<ref>{{cite journal |last1=Stewart |first1=Alexander J. |last2=McCarty |first2=Nolan |last3=Bryson |first3=Joanna J. |title=Polarization under rising inequality and economic decline |journal=[[Science Advances]] |date=2020 |volume=6 |issue=50 |doi=10.1126/sciadv.abd4201 |pmid=33310855 |pmc=7732181 |arxiv=1807.11477 |bibcode=2020SciA....6.4201S |doi-access=free}}</ref> For example, in post-[[World War I]] [[Germany]], the [[Communist Party of Germany]], and the [[Nazism|National Socialists]], a [[fascism|fascist]] party, emerged as the dominant political ideologies and proposed to address Germany's economic problems in drastically different ways.<ref name="sartori-66" /><ref name="sartori-76" /> In [[Venezuela]], in the late 20th century, presidential candidate [[Hugo Chávez]] used economic inequality in the country to polarize voters, employing a popular and aggressive tone to gain popularity.<ref name=":0">{{Cite book |last1=Márquez |first1=Laureano |title=Historieta de Venezuela: De Macuro a Maduro |last2=Eduardo |first2=Sanabria |publisher=Gráficas Pedrazas |year=2018 |isbn=978-1-7328777-1-9 |edition=1st |page=151 |chapter=Llegó la dictablanda |author-link=Laureano Márquez}}</ref>

===The media===
Also stated by Sheena Peckham, algorithms used by social media to operate creates an echo-chamber for the user causing selective exposure and thus leading to online hate, misinformation, malinformation and more (Peckham, 2023). A number of techniques were employed by the researchers and social scientist to trace the relationship between internet usage. Lelkes, along with his colleagues, use state right-of-way laws, which affect the cost of internet infrastructure, as an instrument used for internet access in their country (Lelkes et al. 2017) and discovered a positive relation between internet access and affective polarization in the country. At the same time, (Alcot et al. 2021) conducted another experiment in which individuals in the US. were asked to deactivate their Facebook account for a $102 incentive, prior to the US. midterm election. It was found that those who deactivated their accounts and did not use Facebook were less polarized as compared to those individuals whose accounts were still activated during the experiment.<ref>Peckham, S. (2023) What are algorithms? how to prevent echo chambers, Internet 
Matters. Available at: https://www.internetmatters.org/hub/news-blogs/what-are-algorithms-how-to-prevent-echo-chambers/ (Accessed: 14 February 2024).</ref><ref>Lelkes Y, Sood G, Iyengar S. 2017. The hostile audience: the effect of access to 
broadband internet on partisan affect. Am. J. Political Sci. 61(1):5–20</ref><ref>Alcott, H., Braghieri, L., Eichmeyer, S., & Gentzkow, M. (2020). The welfare effects of 
social media. American Economic Review, 110(3), 629-676</ref>

In addition, Boxell assess ANEX data from 1972-2016 by age cohorts analyzing their likelihood of using social media. He was shocked to found that the largest polarization index over time was occurred among oldest cohort, which was less likely to use social media (Boxell et al., 2017).<ref>Boxell L, Gentzkow M, Shapiro JM. 2017. Greater internet use is not associated with 
faster growth in political polarization among US demographic groups. PNAS 
114(40):10612–17</ref> Thus, he found a small or negative relation between internet usage and polarization. Also, Markus Prior in his article tried to trace the causal link between social media and affective polarization but he found no evidence that partisan media are making ordinary American voter more partisan, thus negating the role of partisan media as a cause of affective polarization (Prior, 2013).<ref>Prior M (2013) Media and political polarization. Annual Review of Political 
Science 16(1): 101–127</ref>

The mass media has grown as an institution over the past half-century. Political scientists argue that this has particularly affected the voting public in the last three decades, as previously less partisan viewers are given more polarized news media choices. The mass media's current, fragmented, high-choice environment has induced a movement of the audience from more even-toned political programming to more antagonistic and one-sided broadcasts and articles. These programs tend to appeal to partisan viewers who watch the polarized programming as a self-confirming source for their ideologies.<ref name="mann-12" /><ref name="hetherington-09" /><ref name="hollander-08">{{cite journal|last=Hollander|first=B.A.|title=Tuning Out or Tuning Elsewhere? Partisanship, Polarization, and Media Migration from 1998 to 2006|journal=Journalism & Mass Communication Quarterly|date=1 March 2008|volume=85|issue=1|pages=23–40|doi=10.1177/107769900808500103|s2cid=144996244}}</ref>

Countries with less diversified but emerging media markets, such as [[China]] and [[South Korea]], have become more polarized due to the diversification of political media.<ref name="yuan-07">{{cite book|last=Yuan|first=Elaine Jingyan|title=The New Multi-channel Media Environment in China: Diversity of Exposure in Television Viewing|year=2007|publisher=Northwestern University|isbn=978-1109940213}}</ref><ref name="kim-11">{{cite book|last=Kim|first=S.J.|title=Emerging patterns of news media use across multiple platforms and their political implications in south korea|year=2011|publisher=Northwestern University|id={{ProQuest|873972899}}}}</ref> In addition, most search engines and social networks (e.g., Google, Facebook) now utilize computer algorithms as filters, which personalize web content based on a user's search history, location, and previous clicking patterns, creating more polarized access to information.<ref>Rushkoff, D. (2010). ''Program or be programmed: Ten commands for a digital age.'' Berkeley, CA: Soft Skull Press.</ref> This method of personalizing web content results in ''[[filter bubble]]s'', a term coined by digital activist [[Eli Pariser]] that refers to the polarized ideological bubbles that are created by computer algorithms filtering out unrelated information and opposing views.<ref>Pariser, E. (2011). ''The filter bubble: What the internet is hiding from you''. New York, NY: The Penguin Press.</ref>

A 2011 study found ideological segregation of online news consumption is lower than the segregation of most offline news consumption and lower than the segregation of face-to-face interactions.<ref>{{Cite journal|last1=Gentzkow|first1=Matthew|last2=Shapiro|first2=Jesse M.|date=2011-11-01|title=Ideological Segregation Online and Offline *|journal=The Quarterly Journal of Economics|volume=126|issue=4|pages=1799–1839|doi=10.1093/qje/qjr044|issn=0033-5533|hdl=1811/52901|s2cid=9303073|url=https://kb.osu.edu/bitstream/1811/52901/1/Mershon_ShapiroJ_photos_2011-10-27.pdf|hdl-access=free}}</ref> This suggests that the filter bubbles effects of online media consumption are exaggerated. Other research also shows that online media does not contribute to the increased polarization of opinions.<ref>{{Cite journal|last1=Hohenberg|first1=Clemm von|last2=Bernhard|last3=Maes|first3=Michael|last4=Pradelski|first4=Bary S.R.|date=2017-05-25|title=Micro influence and macro dynamics of opinions|doi=10.2139/ssrn.2974413 |ssrn=2974413|s2cid=157851503 }}</ref> [[Solomon Messing]] and Sean J. Westwood state that individuals do not necessarily become polarized through media because they choose their own exposure, which tends to already align with their views.<ref>{{Cite journal|last1=Messing|first1=Solomon|last2=Westwood|first2=Sean|date=31 Dec 2012|title=Selective Exposure in the Age of Social Media|journal=Communication Research|volume=41|issue=8|pages=1042–1063|doi=10.1177/0093650212466406|s2cid=35373607}}</ref> For instance, in an experiment where people could choose the content they wanted, people did not start to dislike their political opponents more after selecting between pro or anti immigration content.<ref name="Dahlgren, P. M. 2021">{{cite journal |last1=Dahlgren |first1=Peter M. |title=Forced vs. Selective Exposure: Threatening Messages Lead to Anger but Not Dislike of Political Opponents |journal=Journal of Media Psychology |date=2021 |doi=10.1027/1864-1105/a000302|s2cid=266491415 }}</ref> People did, however, start to counterargue the content.<ref name="Dahlgren, P. M. 2021" />

Academic studies found that providing people with impartial, objective information has the potential to reduce political polarization, but the effect of information on polarization is highly sensitive to contextual factors.<ref>{{Cite journal|last1=Duhaime|first1=Erik|last2=Apfelbaum|first2=Evan|date=2017|title=Can Information Decrease Political Polarization? Evidence From the U.S. Taxpayer Receipt |journal=Social Psychological and Personality Science|volume=8|issue=7|page=736|doi=10.1177/1948550616687126|s2cid=151758489}}</ref> Specifically, polarization over government spending was reduced when people were provided with a "Taxpayer Receipt," but not when they were also asked how they wanted the money to be spent. This suggests that subtle factors like the mood and tone of partisan news sources may have a large effect on how the same information is interpreted. This is confirmed by another study that shows that different emotions of messages can lead to polarization or convergence: joy is prevalent in emotional polarization, while sadness and fear play significant roles in emotional convergence.<ref>Hilbert, M., Ahmed, S., Cho, J., Liu, B., & Luu, J. (2018). Communicating with Algorithms: A Transfer Entropy Analysis of Emotions-based Escapes from Online Echo Chambers. Communication Methods and Measures, 12(4), 260–275. https://doi.org/10.1080/19312458.2018.1479843 ; https://www.martinhilbert.net/communicating-with-algorithms/</ref> These findings can help to design more socially responsible algorithms by starting to focus on the emotional content of algorithmic recommendations.

Research has primarily focused on the [[United States]], a country with high polarization that has also increased over time. In [[Sweden]], on the other hand, there is a stable ideological polarization over time.<ref>{{cite book |last1=Oscarsson |first1=Henrik |last2=Bergman |first2=Torbjörn |last3=Bergström |first3=Annika |last4=Hellström |first4=Johan |title=Demokratirådets rapport 2021: polarisering i Sverige |location=Stockholm |publisher=SNS |year=2021 |isbn=978-9188637567 }}</ref> Experiments and surveys from Sweden also give limited support to the idea of increased ideological or affective polarization due to media use.<ref>{{cite book |last1=Dahlgren |first1=Peter M. |title=Media Echo Chambers: Selective Exposure and Confirmation Bias in Media Use, and its Consequences for Political Polarization |date=2020 |publisher=University of Gothenburg |location=Gothenburg |isbn=978-91-88212-95-5 |url=https://gupea.ub.gu.se/handle/2077/67023?locale=en}}</ref>

{{further|Social media#Political polarization|Echo chamber (media)}}

=== The political context ===
Some of recent studies emphasize the role of electoral context and the way parties interact with each other. For example, a recent study shows that coalition partnership can moderate the extent of affective polarization over parties.<ref name="auto"/> However, this study does not find evidence that the number of political parties and district magnitude that captures the proportionality of electoral systems would influence the extent of affective polarization. Also, electoral context, such as electoral salience, involvement in elections, elite polarization, and the strength of Eurosceptic parties, can intensify the divide.<ref name="doi.org"/>

The impact of redistricting—potentially through [[gerrymandering]] or the manipulation of electoral borders to favor a political party—on political polarization in the United States has been found to be minimal in research by leading political scientists.<ref>{{Cite web |last=Prokop |first=Andrew |date=2014-08-05 |title=Does gerrymandering cause political polarization? |url=https://www.vox.com/2014/8/5/17991982/gerrymandering-political-polarization-partisan |access-date=2024-07-15 |website=Vox |language=en-US}}</ref> [[Ranked-choice voting in the United States|Ranked-choice voting]] has also been put forward as a solution to political polarization.<ref>{{Cite web |last=Slaughter |first=Anne-Marie |date=2019 |title=Idea: Ranked-Choice Voting |url=https://politico.com/interactives/2019/how-to-fix-politics-in-america/polarization/ranked-choice-voting/ |access-date=2024-07-15 |website=politico.com |language=en}}</ref>

When politicians repeatedly favor partisan media outlets, they reinforce their supporters' existing biases, which can further fuel political polarization within the public.<ref>{{Cite web |title=Six ways the media influence elections {{!}} School of Journalism and Communication |url=https://journalism.uoregon.edu/news/six-ways-media-influences-elections |access-date=2024-10-14 |website=journalism.uoregon.edu |language=en}}</ref>