Peer Reviewed Articles
Heerden, Sjoerdje van, and Didier Ruedin. 2017. ‘How Attitudes towards Immigrants Are Shaped by Residential Context: The Role of Neighbourhood Dynamics, Immigrant Visibility, and Areal Attachment’. Urban Studies. Forthcoming.
Ruedin, Didier. 2017. ‘Participation in Local Elections: ‘Why Don’t Immigrants Vote More?’’ Parliamentary Affairs. Forthcoming. doi:10.1093/pa/gsx024 [Link to Publisher | Supplementary and Replication Material | Post-print | Data]
I present a new representative survey on participation in the 2015 municipal elections in the Canton of Geneva, Switzerland, and predict electoral participation with logistic regression models. Most immigrant groups vote less than the majority population. Social origin (resources), political engagement, civic integration and networks, as well as socialization are associated with differences in electoral participation, but contrary to some recent studies, substantive differences between nationalities remain.
Ruedin, Didier and Laura Morales. 2017. “Estimating Party Positions on Immigration: Assessing the Reliability and Validity of Different Methods”. Party Politics. Forthcoming. doi:10.1177/1354068817713122 [Link to Publisher | Supplementary and Replication Material | Post-print]
A systematic assessment of various methods to position political parties on immigration in Austria, Belgium, France, Ireland, the Netherlands, Spain, Switzerland, and the UK, between 1993 and 2013. We find high levels of consistency between expert positioning, manual sentence-by-sentence coding, and manual checklist coding; and poor or inconsistent results with the CMP, Wordscores, Wordfish, and the dictionary approach. An often-neglected method – manual coding using checklists – offers resource efficiency with no loss in validity or reliability.
Berkhout, Joost, and Didier Ruedin. 2017. “Why Religion? Immigrant Groups as Objects of Political Claims on Immigration and Civic Integration in Western Europe, 1995–2009”. Acta Politica. 52(2): 156-178. doi:10.1057/ap.2016.1 [Link to Publisher | Supplementary Material | Pre-print | earlier SOM Working Paper ]
We use claims-making analysis to capture how immigrant groups are differentiated in seven Western European countries. We find that Muslim-related claims-making is associated with the parliamentary presence of anti-immigrant parties and the policy topic under discussion. By contrast, the evidence for policy-oriented and socio-structural explanations is inconclusive.
Ruedin, Didier. 2017. “Citizenship regimes and the politicization of immigrant groups”. Austrian Journal of Political Sciences. 46(1):7-19. doi:10.15203/ozp.1591.vol46iss1 [Open Access | Supplementary and Replication Material]
This article explores how immigrants and their integration are debated across citizenship regimes, with a focus on ‘voiceless’ groups without formal franchise and a precarious residence status: asylum seekers, refugees, and irregular immigrants. Having an ethnic citizenship regime is associated with more claims about voiceless immigrant groups. At the same time, the association between immigrant group size and the extent to which immigrant groups are politicized is moderated by the citizenship regime.
Zschirnt, Eva and Didier Ruedin. 2016. “Ethnic discrimination in hiring decisions: A meta-analysis of correspondence tests 1990–2015”, Journal of Ethnic and Migration Studies, 42(7):1115-34. doi:10.1080/1369183X.2015.1133279 [Link to Publisher | Pre-print on SSRN | Post-print | Replication Material]
We present a meta-analysis of 738 correspondence tests in 43 separate studies conducted in OECD countries between 1990 and 2015. In addition to summarizing research findings, we focus on groups of specific tests to ascertain the robustness of findings, emphasizing (lack of) differences across countries, gender, and economic contexts.
Pecoraro, Marco, and Didier Ruedin. 2016. “A Foreigner Who Doesn’t Steal My Job: The Role of Unemployment Risk and Values in Attitudes towards Equal Opportunities.” International Migration Review. 50(3):628-66. doi:10.1111/imre.12162 [Link to Publisher | peer reviewed FORS Working Paper (pre-print)| ☆ Finalist for the SAGW Prix Relève/Nachwuchspreis 2016]
We examine individual attitudes towards equal opportunities for foreigners and Swiss citizens, using cross-sectional data from the Swiss Household Panel. Individuals with low levels of education tend to oppose foreigners, while the opposition by individuals with high levels of education increases with the risk of unemployment. Values and beliefs explain the negative attitudes of individuals with low levels of education, but not the association with the risk of unemployment for individuals with high levels of education. Clearly, both values and economic factors are important for explaining attitudes towards foreigners.
Ruedin, Didier. 2015. “Increasing validity by recombining existing indices: MIPEX as a measure of citizenship models.” Social Science Quarterly 96(2): 629-638. doi:10.1111/ssqu.12162 [Link to Publisher | Replication Material | Additional figures | Post-print]
It is possible to increase the validity of research by recombining individual indicators of existing indices. This approach is demonstrated by using data from the widely used Migration Integration Policy Index (MIPEX), recombining some of the 148 indicators to approximate Koopmans et al.’s (2005) two-dimensional conception of citizenship models. The recombined MIPEX data match the desired conception of citizenship models and can be applied to all countries covered in the MIPEX. For the first time theoretically predicted ethnic-pluralistic citizenship models (segregationism) are observed.
Ruedin, Didier, Camilla Alberti, and Gianni D’Amato. 2015. “Immigration and integration policy in Switzerland, 1848 to 2014”, Swiss Political Science Review 21(1): 5-22. doi:10.1111/spsr.12144 [Link to Publisher | Post-print | Data]
We provide a systematic and truly historical assessment of immigration and integration policy in Switzerland: between the foundation of modern Switzerland in 1848 and 2014. The most recent MIPEX questionnaire was used to provide a systematic and multidimensional portrait of how immigration and integration policy has evolved in Switzerland. Using these data, we identify three distinctive periods (expansive, restricting, expanding), and argue that the changes in policies reflect the fact that immigrants are increasingly accepted as a permanent feature of Swiss society.
Morales, Laura, Jean-Benoit Pilet, and Didier Ruedin. 2015. “The Gap between Public Preferences and Policies on Immigration: A Comparative Examination of the Effect of Politicization on Policy Congruence” Journal of Ethnic and Migration Studies, 41(9):1495-1516. doi:10.1080/1369183X.2015.1021598 [Link to Publisher | Pre-print | Supplementary Material]
In this article we examine the potential drivers of variations in the opinion-policy gap on immigration in seven countries (1995–2010). We analyse the effect of the politicization of immigration on this opinion-policy gap. The strength of anti-immigrant parties is unrelated to the opinion-policy gap on immigration. The salience of the issue and the intensity of the public debate are associated with the opinion-policy gap, and the combination of negative attitudes with extensive media coverage seems particularly conducive to policy congruence.
Ruedin, Didier. 2013. “The role of language in the automatic coding of political texts.” Swiss Political Science Review 19(4): 539-45. doi:10.1111/spsr.12050 [Link to Publisher | Post-print | Replication Data]
To what extent does the source language of a text affect automatic approaches to coding party manifestos? Compares German-language and French-language manifestos using a keyword-based dictionary approach and Wordscores. Because of language differences, both stemming and particularly stop words are important to obtain comparable results for Wordscores.
Ruedin, Didier. 2013. “Obtaining party positions on immigration in Switzerland: Comparing different methods.” Swiss Political Science Review 19(1): 84-105. doi:10.1111/spsr.12018 [Link to Publisher | Post-print | Replication Data | R Code | Stopwords]
This paper examines different methods for obtaining party positions on immigration in retrospective. While there are high correlations between many methods, the different methods tend not to agree on the exact positions.
Ruedin, Didier. 2012. “The representation of women in national parliaments: A cross-national comparison.” European Sociological Review 28(1): 96–109. doi:10.1093/esr/jcq050 [Link to Publisher | Post-print]
Women’s representation in national parliaments is examined using a large cross-national sample. In line with some recent contributions, this article finds that the proportion of women in parliament is explicable in terms of culture—particularly attitudes towards women as political leaders. Once controlling for regional or cultural differences, the provision of voluntary party quotas does not appear to be significant at the national level.
Ruedin, Didier. 2012. “Individual representation: A different approach to political representation.” Representation 48(1): 115–29. doi:10.1080/00344893.2012.653248 [Link to Publisher | Post-print | R-package | old version with more figures: peer reviewed DISC Working Paper | ☆ Short-listed for the SPSA Prize for the Best Political Science Journal Article by a Young Researcher 2014]
This article presents a new conceptualisation and measure of political representation to complement conventional approaches. Individual representation scores place the individual rather than the legislature at the centre, providing a fresh perspective on the relationship between inequality and representation. They are calculated by comparing first the position of the individual with other citizens, and second the position of the individual with the legislature. The article outlines how to make sense of individual representation scores and includes an empirical example.
Ruedin, Didier. 2010. “The relationship between levels of gender and ethnic group representation.” Studies in Ethnicity and Nationalism 10(2): 92–106. doi:10.1111/j.1754-9469.2010.01066.x [Link to Publisher | Post-print | Data]
This article examines the relationship between levels of gender representation and levels of ethnic group representation in national parliaments. Taagepera (1994) and Lijphart (1999) predicted that because of shared mechanisms and covariates levels of representation in the two forms should be positively correlated. There is no evidence of an association between levels of gender and ethnic group representation. Representation scores tend to be higher in the forms of representation that are thought to be more salient.
Ruedin, Didier. 2009. “Ethnic group representation in a cross-national comparison.” The Journal of Legislative Studies 15(4): 335–54. doi:10.1080/13572330903302448 [Full Article | Data | Post-print | ☆ Winner of the 2010 SNIS International Geneva Award]
This paper compares the levels of ethnic group representation in parliament in 95 democracies. Considering both electoral and cultural variables, the results cast doubt on whether the role of the electoral system in shaping political representation is dominant. In contrast to what much of the literature suggests, once controlling for the ethnic make-up of society and cultural attitudes, electoral aspects seem of little significance. Levels of ethnic group representation are best explained with cultural variables, in particular liberal attitudes towards marginalised groups in society.
Ruedin, Didier. 2007. “Testing Milbrath’s 1965 Framework of Political Participation: Institutions and Social Capital.” Contemporary Issues and Ideas in Social Sciences 3(3). [Open Access | Full Paper | Full Simulation Code]
A computer simulation is used to empirically test Milbrath’s 1965 framework of political participation. It is found that both political institutions and social capital are significant contributors to political participation. Rather than the time spent in a community, personal contacts appear to be more important for political participation.
Peer Reviewed Monograph
Ruedin, Didier. 2013. Why Aren’t They There? The Political Representation of Women, Ethnic Groups and Issue Positions in Legislatures. Colchester: ECPR Press. [Link to Publisher | TOC | Sample Chapter | e-Book | e-Book (ECPR) | Book Review]
A comprehensive study of political representation in a cross-national format, examining the representation of women, ethnic groups, and policy positions.
Pecoraro, Marco, and Didier Ruedin. 2017. ‘The Share of Foreigners in One’s Occupation and Attitudes Towards Foreigners’. IRENE Working Papers 17 (6): 1–37. [ Full Paper ]
Ruedin, Didier. 2017. “Qualitative Regressions: Model the uncertainty in your (qualitative) data to make better inferences.” SocArXiv Working Paper, 1–12. DOI:10.17605/OSF.IO/TWQ5U [Full Paper]
Ruedin, Didier. 2017. ‘Not Everyone is Xenophobic in South Africa’. SocArXiv Working Paper, 1–4. DOI:10.17605/OSF.IO/3FUB5 [Full Paper]
Ruedin, Didier. 2017. “Attitudes to Immigrants of the Moderate Left in Switzerland.” SocArXiv Working Paper, 1–4. DOI:10.17605/OSF.IO/KBRKQ [Full Paper]
Ruedin, Didier. 2011. “Conceptualizing the integration of immigrants and other groups.” COMPAS Working Paper 89. [Full Paper]
This paper addresses the integration of immigrants and other societal groups from a conceptual point of view. With increased conceptual clarity and by working toward an objective definition as far as possible, the paper creates a possible foundation on which indicators of integration can be built. Integration is conceptualized as proximity, and a distinction is drawn between the integration of groups and individuals. It is argued that integration should be understood as assimilation in relevant dimensions, whereas in other dimension significant differences are accepted.
Ruedin, Didier. 2011. “The reliability of MIPEX indicators as scales.” SOM Working Paper 3: 1–19. [Full Paper | Replication Data]
This paper examines the reliability of the Migrant Integration Policy Index (MIPEX) as a scale. The results of the reliability analysis suggest that overall, MIPEX is a reliable scale. Moreover, the individual strands are also reliable, although in most instances the scales could be improved by removing specific items. In contrast, however, most of the dimensions identified are not reliable. It seems that the number of indicators in MIPEX could be reduced, and the data are probably better presented in a different way than the six strands MIPEX uses.
Ruedin, Didier. 2011. “The role of social capital in the political participation of immigrants: Evidence from agent-based modelling.” SFM Discussion Paper 27. [Full Paper | Full Simulation Code]
Research commonly finds that immigrants are less likely to participate in politics than members of the mainstream society. Using agent-based modelling, this paper suggests that social capital and contacts in the community may be a relevant mechanism to account for differences in political participation observed between immigrants and the mainstream society.
Ruedin, Didier. 2010. “Wie würden Personen ohne den roten Pass wählen: Wahlverhalten von Ausländerinnen und Ausländern.” SFM Discussion Paper 24. [Full Paper]
Dieser Artikel untersucht das Wahlverhalten von Ausländerinnen und Ausländern und eingebürgerten Personen: Gehen sie mehr oder weniger häufig wählen als Schweizerinnen und Schweizer? Empirische Forschungen im Ausland und in der Schweiz zeigen auf, dass sich das Wahlverhalten von Ausländer und Ausländerinnen den lokalen Gegebenheiten entspricht, weil das Umfeld für das Wahlverhalten dominant ist.
Ruedin, Didier. 2009. “The proportion of women in national parliament as a measure of women’s status in society.” Oxford Sociology Working Papers 5. [Full Paper]
Representation in decision-making is often used as an indicator of the wider integration of women in political and everyday life. It is argued that the proportion of women in parliament is a reasonably good indicator of status, with the benefit of being based on readily available data.
Van der Brug, Wouter, Gianni D’Amato, Joost Berkhout, and Didier Ruedin, eds. 2015. The Politicisation of Immigration: A Comparative Study of Seven Countries (1995-2009). Abingdon: Routledge. [Link to Publisher]
This edited book examines the politicization of immigration in seven Western European countries, drawing on research undertaken in the SOM Project.
Söderström, Ola, Shalini Randeria, Didier Ruedin, Gianni D’Amato, and Francesco Panese, eds. 2013. Critical Mobilities. Abingdon: Routledge. [Link to Publisher | Cover and TOC | Book Review (in French) | Extract]
This edited book brings together the work of several scholars affiliated with the MOVE Network on mobility studies. Instead of assuming a seamless world of flows, as is common in mobility studies, the volume highlights questions of power, inequality, and moorings as integral to mobility of capital, goods, images, practices, or people. My role was managing the publication, and trying to encourage contributors to be more systematic, precise and coherent in their accounts of mobility.
Chapters in Edited Volumes
Ruedin, D. 2019 forthcoming. ‘Ethnic and Regional Minorities’. In Handbook of Political Representation in Liberal Democracies, edited by Robert Rohrschneider and Jacques JA Thomassen. Oxford: Oxford University Press. Under contract.
Ruedin, Didier, Sieglinde Rosenberger, and Nina Merhaut. 2017 forthcoming. ‘Tracing Anti-Deportation Protests: A Longitudinal Comparison of Austria, Germany, and Switzerland’. In Comparative Analysis of Protest Movements in Refugee, Asylum and Deportation Policies, edited by Sieglinde Rosenberger. IMISCOE Research. New York: Springer. [Supplementary analysis as SSRN Working Paper on protest against the deportation of rejected asylum seekers in the local and national press in Switzerland]
Rosenberger, Sieglinde, and Didier Ruedin. 2017. ‘The Politicization of Asylum Seekers and Other Immigrant Groups in a Comparative Perspective’. In Asylrecht Als Experimentierfeld: Eine Analyse Seiner Besonderheiten Aus Vergleichender Sicht, edited by Franz Merli and Magdalena Pöschl, 13–26. Wien: Verlag Manz. [Link to Publisher]
Van der Brug, Wouter, Gianni D’Amato, Joost Berkhout, and Didier Ruedin. 2015. “A Framework for Studying the Politicisation of Immigration.” In The Politicisation of Immigration, edited by Wouter van der Brug, Gianni D’Amato, Joost Berkhout, and Didier Ruedin. Abingdon: Routledge.
Van der Brug, Wouter, Didier Ruedin, Joost Berkhout, and Kevin Cunningham. 2015. “A Cross-Country Comparison.” In The Politicisation of Immigration, edited by Wouter van der Brug, Gianni D’Amato, Joost Berkhout, and Didier Ruedin. Abingdon: Routledge.
Simona, Jehane, Marco Pecoraro, and Didier Ruedin. 2014. “Gender Gaps in Mental Health among the Migrant Population in Switzerland.” In Women’s Mental Health: Resistance and Resilience in Community and Society, edited by Nazilla Khanlou and F. Beryl Pilkington. [Link to Publisher | Post-Print]
Ruedin, Didier, and Gianni D’Amato. 2013. “Immigrant Integration, Public Acceptance and Social Cohesion.” In 10 Observations on the Future of Migration: Costs, Benefits and Policy Responses, edited by Veronika Bilger, Sabine Klinglmair, and Martin Hofmann, 125–50. Vienna: International Centre for Migration Policy Development (ICMPD). [Executive Summary | peer reviewed Report]
Recent decades saw increasing levels and diversity of immigrant populations in Europe, often seen as a challenge to social cohesion. Reactions to this perceived challenge differ because immigrants adjust to the recession, and because of historical legacies of immigration and the welfare state. Adapted version of a report published by the Migration Policy Institute as part of the EUI series on Improving US and EU Migration Systems: here.
Söderström, Ola, Shalini Randeria, Didier Ruedin, Gianni D’Amato, and Francesco Panese. 2013. “Of Mobilities and Moorings: Critical Perspectives.” In Critical Mobilities, edited by Ola Söderström, Shalini Randeria, Didier Ruedin, Gianni D’Amato, and Francesco Panese, 1–22. Abingdon: Routledge.
Ruedin, Didier. 2009. “Symbolic and Ideological Representation in National Parliaments: A cross-national comparison of the representation of women, ethnic groups, and issue positions in national parliaments.” PhD Thesis. University of Oxford. [First Chapter | ☆ ORSAS Scholarship]
Comparative quantitative analysis of political representation. Examines the factors that are associated with levels of gender, ethnic group, and ideological representation in a cross-national comparative study, finding that cultural variables and aspects of salience are probably more central to understanding political representation than generally acknowledged in the literature.
Ruedin, Didier. 2005. “A Simulation of Political Participation.” MSc Thesis. University of Oxford. [Full Document | Derived Article | Full Simulation Code | ☆ Distinction, ☆ Best dissertation]
Agent-based (ABM) computer simulation of political participation, implementing Milbrath’s framework of political participation.
Reports & Other
Efionayi-Mäder, Denise, and Didier Ruedin. 2017. Etat des lieux du racisme anti-Noir·e en Suisse. SFM Studies 67. Neuchâtel: SFM University of Neuchâtel. [Report (in French), Report (in German), Report (in Italian TBA)]
Ambruso, Martina, Denise Efionayi-Mäder, and Didier Ruedin. 2017. Accès aux prestations municipales de proximité : collectivités migrantes dans les quartiers de la Ville de Genève. SFM Studies 66. Neuchâtel: SFM University of Neuchâtel. [Report (in French)]
Fibbi, Rosita, and Didier Ruedin. 2016. “La participation des résidents étrangers aux élections municipales d’avril 2015 à Genève.” Geneva: Bureau de l’intégration des étrangers. [Report (in French) | Summary (in French) | Executive Summary (in French) | Raw Data]
Representative survey of voters in the canton of Geneva focusing on reasons why foreign citizens are participating less in local elections.
Morlok, Michael, Harald Meier, Andrea Oswald, Denise Efionayi-Mäder, Didier Ruedin, Dina Bader, and Philippe Wanner. 2016. “Sans-Papiers in der Schweiz 2015.” Bern: Staatssekretariats für Migration (SEM). [Report DE | FR | Sample news coverage (in English)]
Situation of sans-papiers in Switzerland, including an estimate of the number of irregular migrants in Switzerland
Ruedin, Didier and Denise Efionayi-Mäder. 2015. “Civil Society Platform on Migration and Development: Assessment of Needs and Potential.” Bern: Swiss Civil Society Organizations Platform on Migration and Development. [Draft Report]
Ruedin, Didier. 2015. “Rassistische Diskriminierung und Rassismus in der Schweiz: Datenlage.” In Rassistische Diskriminierung in der Schweiz: Bericht der Fachstelle für Rassismusbekämpfung 2014. Bern: Fachstelle für Rassismusbekämpfung FRB. [Full Report | Longer (Standalone) Version]
Report on racial discrimination in Switzerland drawing on existing data.
Ruedin, Didier, and Denise Efionayi-Mäder. 2014. “Wenn aus vorläufig endgültig wird…” Terra cognita, 25:102-4. [Open Access: Full Article | Detailed Report and Analysis | Press Coverage]
Study of temporary admitted immigrants, highlighting that for many this ‘temporary’ status is rather long-term.
Iseni, Bashkim, Didier Ruedin, Dina Bader, and Denise Efionayi-Mäder. 2014. “The Population of Bosnia and Herzegovina in Switzerland”. Bern: Federal Office for Migration (FOM) and Swiss Agency for Development and Cooperation (SDC). [D F | example News coverage | Radio interviews]
Description of the Bosnian immigrant population in Switzerland, with a particular focus on their potential in development in the country of origin.
Ruedin, Didier. 2014. “Where Are the Ethnic Minorities?” Government Gazette, July, 54. [Article]
Summary of my research on the political representation of ethnic groups in national legislatures.
Galanxhi, Emira, Majlinda Nesturi, Ledia Thomo, Elira Jorgoni, and Didier Ruedin. 2014. “Migration in Albania”. Tirana: INSTAT. [Full Report]
Comprehensive portrait of migration in Albania (internal, intrnational), using Census data
Pecoraro, Marco, and Ruedin, Didier. 2013. “Wie Arbeitslosigkeitsrisiko und kulturelle Werte die Einstellung gegenüber Ausländern beeinflussen.” Die Volkswirtschaft 11: 54-8. [Full Article]
Summary of our research on attitudes to foreigners.
Ruedin, Didier with Gianni D’Amato, Nicole Wichmann, and Marco Pecoraro. 2013. Migrationsängste der Schweizer Bevölkerung: Eine Studie im Auftrag von swissstaffing. [Report | Newspaper Article]
Comparison of the profiles of newly arrived immigrants and Swiss workers who entered the labour market in the past three years. Generally there is little competition in the labour market. Despite this, there is unease with immigrants. Using a representative survey, I show that most Swiss citizens are not strongly opposed to immigrants, but there are clear differences in how various immigrant groups are perceived.
Ruedin, Didier. 2013. “The Politicization of Immigrant Groups.” FORUM magazine 8: 117-9. [Full Paper]
Ruedin, Didier, and Marco Pecoraro. 2013. “Attitudes toward Foreigners in Switzerland: Of Education and Values.” FORUM magazine 8: 112-3. [Full Paper]
Ruedin, Didier. 2012. “Legal and Policy Situation of Immigrants: Switzerland.” SOM Working Paper 5: 1–15. [Full Paper]
Wichmann, Nicole, Michael Hermann, Gianni D’Amato, Denise Efionayi-Mäder, Rosita Fibbi, Joanna Menet, Didier Ruedin. 2011. Gestaltungsräume im Föderalismus: Migrationspolitik in den Kantonen. Bern: EKM. [I was responsible for statistical analyses, German | French | Italian | Romansh]
Migration policies in the different Swiss cantons.
Ruedin, Didier. 2011. “Indicators of the political opportunity structure (POS).” SOM Working Paper 1: 1–19. [Full Paper]
Ruedin, Didier. 2011. “Demographics of immigration: Switzerland.” SOM Working Paper 9: 1–19. [Full Paper]
Ruedin, Didier. 2010. “Why aren’t they there? Ethnic minorities in parliaments.” FORUM magazine 7: 55–7. [Full Paper]
Ruedin, Didier. Agrmt: Agreement A in R. R-Forge, 2012. http://agrmt.r-forge.r-project.org/. [CRAN]
This package calculates agreement in ordered rating scales. It implements van der Eijk’s (2001) measure of agreement “A”, which can be used to describe agreement, consensus, or polarization among respondents.
Ruedin, Didier. Polrep: Political Representation in R. R-Forge, 2012. http://polrep.r-forge.r-project.org/.
Implementation of different measures of political representation, covering both descriptive representation (unordered groups) and substantive representation (issue positions). Includes functions to calculate individual representation scores.
My Dataverse: https://dataverse.harvard.edu/dataverse/ruedin
My Figshare account: http://figshare.com/authors/Didier_Ruedin/100835
Dataverse of the SOM project: https://dataverse.harvard.edu/dataverse/som