Cited by 18Electoral Systems and Political ParticipationSpanish History and PoliticsPolitical Dynamics in Latin America

Cuarenta años de polarización ideológica en España

Open access
Rodriguez-Virgili, Jordi, Portilla-Manjón, Idoia, Sierra-Iso, Aurken·2022·Revista Empresa y Humanismo

Abstract

Este artículo analiza la evolución de la polarización ideológica en el sistema de partidos español desde 1979. Se propone una reformulación del índice de Dalton para medir la polarización en España y se aplica a las 14 elecciones generales celebradas desde la aprobación de la Constitución. Los resultados indican una evolución con dos periodos distintos de siete elecciones cada uno y un claro aumento de la polarización ideológica desde 2015, alcanzando un máximo histórico en la actualidad. La medición de la polarización ideológica se complementa con la volatilidad y la competencia electoral generada por la llegada de nuevos partidos. Los mayores incrementos de la polarización se produjeron en elecciones que encajan en el concepto de elecciones críticas, es decir, elecciones que producen un cambio sustancial y duradero en los alineamientos electorales

AI snapshot

Written from the paper’s full text.

TL;DR

This article reformulates Dalton's ideological polarization index for the Spanish case and applies it to the 14 general elections held since the 1978 Constitution, finding two distinct seven-election periods and a sustained rise in polarization since 2015 to a historic maximum. The authors complement the index with electoral volatility and competition measures, linking the largest polarization increases to "critical elections" (1982 and 2015).

Key findings

  • Polarization follows two periods of seven elections each: 1979–2000, where after a sharp 1982 rise the general trend is downward, and 2004–2019, where it rises continuously, reaching 5.43 points after the November 2019 election, its historic maximum.
  • Lowest values are 1979 (3.71) and 2000 (3.86); highest are 1982 (5.32) and 2015 (5.43). The 1982 increase of 1.61 points is the largest in the series, versus only 0.15 points after 1996.
  • Mean electoral volatility across the 14 elections is 15.26, five points above the European average since 1945. 1982 had alteration volatility of 43.8 (highest total volatility in Europe since 1871), and 2015 had total volatility of 35.5 with regeneration volatility of 19 points, the highest regeneration volatility in Europe since 1945.
  • The only statistically significant Spearman coefficient (α = .05) among IP and alternation, regeneration and total volatility is 0.552, showing a positive relation between polarization and alternation volatility. Electoral competition peaked in 1982 (21.86 points), hit a historic low in 1996 (1.17), and right-bloc competition reached its highest value since 1979 in April 2019 (0.84).

Methods

  • Design: longitudinal measurement of ideological polarization in the Spanish party system across 14 general elections (Congress of Deputies), March 1979 to November 2019; 1977 is excluded as pre-constitutional and lacking party-placement data.
  • Data: vote results from the Ministry of the Interior; party ideological placements mostly from CIS post-electoral barometers, except 1979 and 1982, which use the nearest pre-electoral surveys that asked about party placement (survey 1157, July 1978; survey 1279, April 1981). Only the five parties with the greatest parliamentary representation in each election are included, so vote shares do not sum to 100%.
  • Analysis: Dalton's standard-deviation-based polarization index, weighted by voters and vote share, with the divisor changed from 5 to 4.5 to fit the CIS 1–10 placement scale so the index still ranges 0–10. Volatility uses Chiaramonte and Emanuele's Pedersen-index data; electoral competition is measured as the vote gap between the two leading parties and between the first and second party of each bloc.

Limitations

  • Stated by the paper: it offers only a general framework of the evolution of ideological polarization; future work should analyze social differences among voters (age, gender, education, interest in politics) and the causes of polarization change, including media consumption, technological disruption and social networks, and whether the variables Gidron et al. identify for affective polarization also explain ideological polarization across countries.
  • Evident in the text: the index includes only the top five parties per election, which the authors acknowledge leaves vote shares below 100% and requires this to be accounted for in the calculation; the choice of parties is a judgment call that could exclude relevant actors or add noise.
  • Evident in the text: results differ from those of Casal Bértoa, Simón and Rodríguez-Teruel, which the authors attribute mainly to their own formula adjustment and to differences in the period analyzed, indicating measurement choices materially affect the findings.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.15581/015.xxv.2.75-103

Cites

54 of 54 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 5 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    The evolution of ideological polarization in Spain from 1979 to 2019 has two distinct periods of seven elections each: 1979-2000 and 2004-2019.

    “Los resultados indican una evolución con dos periodos distintos de siete elecciones cada uno”
    • Also stated in: § 2.2. Volatilidad y competencia electoral · plain
      “La evolución de la polarización en España marca dos períodos distintos de siete elecciones cada uno: de 1979 a 2000 y de 2004 a 2019.”
    Quote in the paperSubstantial claim
  • Findingown data

    The 1982 increase in polarization was the largest in Spain, 1.61 points.

    “El primer incremento de 1982 es el mayor que ha experimentado la polarización en España, aumentando en 1,61 puntos”
    Quote in the paperNot a substantial claim
  • Findingown data

    Ideological polarization in Spain reached its historical maximum in the current period, with an index of 5.43 after the November 2019 elections.

    “alcanzando un máximo histórico en la actualidad.”
    • Also stated in: § 2.2. Volatilidad y competencia electoral · plain
      “alcanzando los 5,43 puntos tras las elecciones de noviembre de 2019, su máximo histórico.”
    Quote in the paperSubstantial claim
  • Findingreasoning

    The 1979 elections produced the lowest polarization index in the history of Spanish democracy, 3.71.

    “Tras 40 años de Dictadura, los españoles optaron por fuerzas mayoritariamente centristas, ofreciendo el IP más bajo de la historia de la democracia en España, un 3,71”
    Quote in the paperNot a substantial claim
  • Findingreasoning

    The largest increase in polarization between 2004 and 2019 occurred after the 2015 elections.

    “El mayor incremento de la polarización entre 2004 y 2019 se produjo tras las elecciones de 2015”
    Quote in the paperNot a substantial claim
  • May combine two claims. 15
  • Classified as probably not a substantial claim. 1
  • May combine two claims.

    Findingown data

    The 1982 elections had a polarization index of 5.32, the second highest since the return to democracy.

    “El mínimo histórico alcanzado a partir de 1979 contrasta con el IP de 1982 (5,32), el segundo más alto desde el retorno a la democracia.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingreasoning

    The 2015 elections pushed polarization above 5 points, something that had only occurred in 1982.

    “Este hecho impulsó la polarización, que rompió la barrera de los 5 puntos, algo que solo había ocurrido en 1982.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingown data

    In the first period (1979-2000), the general trend of the polarization index was downward, although it began with a strong increase.

    “Aunque en la primera etapa el Índice de Polarización (IP) comienza con un fuerte incremento, la tendencia general es a la baja.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingreasoning

    From 2015 to 2019, polarization in Spain continued to rise, more moderately, remaining above 5 points.

    “Desde entonces y hasta 2019, la polarización en España ha seguido subiendo, aunque de forma más moderada, manteniéndose por encima de la barrera de los 5 puntos.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingnone given

    The 2015 elections coincided with the entry of new national parties (Podemos and Ciudadanos) and the rupture of the imperfect bipartisanship that had prevailed in Spain since the Transition.

    “coincidiendo con la entrada de nuevos partidos nacionales (Podemos y Ciudadanos) y la ruptura del bipartidismo imperfecto que había imperado en España desde la Transición.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data

    The only statistically significant Spearman coefficient (α = .05) between IP and alternation, regeneration, and total volatility is 0.552, showing a positive relationship between IP and alternation.

    “Si medimos la correlación del IP con la alternancia, la regeneración y la volatilidad total, el único coeficiente de Spearman que es estadísticamente significativo ( α = .05)es el valor 0,552, que muestra una relación positiva entre IP y Alternancia: un nivel alto de IP corresponde a una volatilidad alta de la alternancia.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingcitation

    The 1982 elections had the highest total volatility in Europe since 1871, with alteration volatility of 43.8.

    “La alta volatilidad por alteración de esas elecciones (43,8), además de ganarse el apelativo de terremoto electoral, las sitúa como las elecciones con mayor volatilidad total en Europa desde 1871”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [45]
  • May combine two claims.

    Findingreasoning

    Regeneration volatility in 2015 rose to 19 points, the highest regeneration volatility in Europe since 1945.

    “Esto hizo que la volatilidad de la regeneración subiera hasta los 19 puntos, la mayor volatilidad de la regeneración en Europa desde 1945.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingreasoning

    In 1982, adding UCD's 11 seats, only 30 seats were left to distribute among seven political forces, greatly reducing the weight of anti-system parties.

    “Sumando los 11 escaños obtenidos por UCD, sólo quedaron 30 escaños a repartir entre siete fuerzas políticas, lo que redujo en gran medida el peso de los partidos antisistema.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingnone given

    In the 1979 elections, the electorate was very divided: 41.3% of votes went to the left and 42.9% to the right.

    “En las elecciones de 1979 el electorado estaba muy dividido: el 41,3% de los votos fueron para la izquierda y el 42,9% para la derecha.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingnone given

    In November 2019, PP recovered and Ciudadanos lost more than four million votes.

    “La repetición de las elecciones de noviembre de 2019, en la que el PP se recuperó y Ciudadanos perdió más de cuatro millones de votos”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingreasoning

    The 1982 and 2015 elections are the two cases that break the normality of the volatility trend, for different reasons.

    “Las elecciones de 1982 y 2015 son los dos casos que rompen la normalidad de la tendencia, aunque por motivos diferentes.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingown data

    In 2015, volatility was 35.5, 20 points above the historical mean of the country, making it the second most volatile election since 1979.

    “En primer lugar, la volatilidad fue 20 puntos superior a la media histórica del país (35,5), una cifra que, aunque inferior a la de 1982, las sitúa como las segundas elecciones más volátiles desde 1979.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Interpretationreasoning

    Los resultados que obtienen Simón y Rodríguez-Teruel son diferentes a los nuestros, debido principalmente a nuestro ajuste del modelo y a la diferencia en el periodo analizado.

    “Al igual que nosotros, utilizan el índice de polarización de Dalton, aunque los resultados que obtienen son diferentes a los nuestros, debido principalmente a nuestro ajuste del modelo y a la diferencia en el periodo analizado.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisereasoning

    Tanto Simón y Rodríguez-Teruel como nosotros utilizamos datos de las encuestas postelectorales del CIS, donde la escala de ubicación de los partidos es de 1 a 10.

    “Tanto Simón y Rodríguez-Teruel como nosotros utilizamos datos de las encuestas postelectorales del CIS, donde la escala de ubicación de los partidos es de 1 a 10, por lo que es necesario ajustar el divisor de la fórmula de Dalton y fijarlo en 4,5, que es la distancia máxima entre cada polo y el centro.”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisereasoning

    Simón y Rodríguez-Teruel utilizan el índice de polarización de Dalton, al igual que nosotros.

    “Al igual que nosotros, utilizan el índice de polarización de Dalton, aunque los resultados que obtienen son diferentes a los nuestros, debido principalmente a nuestro ajuste del modelo y a la diferencia en el periodo analizado.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Dalton, R. J. (2008) source
16 of 16
  • The paper relies on this without support.

    No research center in Spain conducts a systematic study on political polarization comparable to the periodic studies by the Pew Research Center or CSES.

    “En España, ningún centro de investigación realiza un estudio sistemático sobre la polarización política como el que de forma periódica realiza el Pew Research Center estadounidense o el Center or the Comparative Study of Electoral Systems (CSES).”
  • The paper relies on this without support.

    Polarization does not fully explain the political changes in Spain since 1979, nor the electoral strategy and behavior of political parties.

    “La polarización no explica por completo los cambios políticos que se han producido en España desde 1979, ni tampoco la estrategia electoral y el comportamiento de los partidos políticos.”
  • The paper relies on this without support.

    Los partidos prefieren formar pactos con partidos del mismo bloque ideológico y evitan pactar con partidos de bloques diferentes.

    “La mayor polarización y la elevada complejidad del actual sistema de partidos español pueden facilitar los pactos entre partidos situados en un mismo bloque, pero dificultan los acuerdos entre los que pertenecen a bloques diferentes.”
3 of 3

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • The reported 2015 and November 2019 polarization peaks are equal

    Major

    The paper reports an index of 5.43 for both 2015 and November 2019. Those values do not support its claim that polarization continued to increase after 2015 to reach a new maximum in November 2019.

  • The 1982 competition maximum reverses the paper's definition

    Major

    The paper defines a smaller vote-share gap as greater electoral competition. Calling the roughly 22-point gap in 1982 a maximum of competition applies that definition in reverse.

  • The 2015 election is numbered as the ninth legislature

    Minor

    The paper calls the 2000 election the seventh legislature. Its election sequence then places 2004 eighth, 2008 ninth, 2011 tenth and 2015 eleventh, contradicting its designation of 2015 as ninth.

3 of 3

Cites

Flagged first, then by citations

1 of the 55 references couldn’t be matched to a known paper.

Research works printed but not linked: 9

  1. Casal Bértoa, Fernando (2019), "Causas y consecuencias de la polarización", Cuadernos de Pensamiento Político, nº 64, pp. 5-16.
  2. Gidron, Noam; Adams, James y Horne, Will (2018), "How Ideology, Economics and Institutions Shape Affective Polarization in Democratic Politics". Presented at the Annual Conference of the American Political Science Association, Boston, August 30-September 2.
  3. Knutsen, Oddbjørn y Kumlin, Staffan (2003), "Value Orientations and Party Choice-A Comparative Longitudinal Study of Five Countries", Presented at the 2nd ECPR Conference, Marburg, 18-21 September, pp. 18- 21.
  4. Maihold, Günther (2007), "La crispación. Instrumentos y efectos de la polarización política en España", en España: Del Consenso a La Polarización: Cambios En La Democracia Española, pp. 393-408.
  5. Mainwaring, Scott (ed.) (1996), Building Democratic Institutions: Party Systems in Latin America, Stanford Univ. Press, Stanford.
  6. Maravall, José Antonio (1981), "Los apoyos partidistas en España: polarización, fragmentación y estabilidad", Revista de Estudios Políticos, vol. 23, pp. 9-32.
  7. Rama Caamaño, José (2016), "Ciclos electorales y sistema de partidos en España, 1977-2016", Revista Jurídica, vol. 34, pp. 241-266.
  8. Santamaría, Julián; Rabasco, María Esther y Toharia, Luis (eds.) (1982), Transición a la democracia en el sur de Europa y América Latina, Centro de Investigaciones Sociológicas, Madrid.
  9. Schmitt, Johannes (2016), "How to Measure Ideological Polarization in Party Systems", Presented at the ECPR Graduate Student Conference, Tartu, 10-13 July.

Cited by

Sorted by citations

Authors
Rodriguez-Virgili, J., Portilla-Manjón, I., & Sierra-Iso, A.
Venue
Revista Empresa y Humanismo
Published
2022-06-24
Pages
75-103
ISSN
  • 1139-7608 (ISSN-L)
  • 2254-6413
OpenAlex
W4283587798
Cited by
18
References
55
Citations by year
2026: 1 · 2025: 7 · 2024: 4 · 2023: 6
FWCI
14.02
Type
journal article
Language
es
Open access
Locations
  • Revista Empresa y Humanismo (publishedVersion, cc-by-nc-nd)
  • Deposito Adademico Digital Universidad De Navarra (University of Navarra) (submittedVersion, other-oa)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
Topics
  • Social Sciences › Political Science and International Relations › Electoral Systems and Political Participation
  • Social Sciences › Arts and Humanities › History › Spanish History and Politics
  • Social Sciences › Political Science and International Relations › Political Dynamics in Latin America
Keywords
ideological polarization, Spanish party system, general elections, electoral volatility, electoral competition, new political parties, critical elections, electoral realignment, Spanish Constitution

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