Segregation describes the process of unmixing different elements in an observation area. Segregation is used when the tendency towards polarization and spatial division of the elements according to certain properties can be observed. The observation area is segregated along certain characteristics if a certain group or a specific element is concentrated in parts of the observation area, but is underrepresented in others.
City as an example
A frequent example or field of observation in sociological, geographical or economic studies are segregation processes within cities . This is where these processes come to light, as in terms of certain characteristics (e.g. income , ethnicity , religion ) in the city , very different population groups usually live together. It is now noticeable that urban space is segregated along these characteristics.
The phenomenon of urban segregation can be observed very early on. Already in the medieval and early modern cities of Europe (compare urban development ) there was a spatial separation, for example, of merchants and craftsmen in their own parts of the city. In addition to this segregation along the lines of occupation, there is also segregation according to ethnic and religious characteristics, for example in the case of the Jewish ghetto or the even more fragmented quarters of the classical oriental city, which are even more divided according to religion and ethnic group . On Muslim segregation see al-Walā 'wa-l-barā' .
Even today, sociologists and urban planners continue to observe segregation effects. In North American cities, this is evident in the neighborhoods that are almost exclusively inhabited by a certain group of immigrants (China Town, Greek Town, the Harlem district in New York). But also in European cities there are sometimes individual city districts with a high proportion of immigrant (former) guest workers from the Mediterranean region or with highly qualified foreign workers. Increased segregation in terms of education and income levels can also be observed. This increasingly creates a private area that is closed off from unauthorized persons (“ gated communities ”). The degree of segregation thus serves as an indicator of a polarization of society and, if the individual groups of characteristics are too clearly separated, it can indicate the risk of the development of conflict-ridden sub-societies. (See also parallel society )
In large European cities, income segregation is particularly pronounced where the structural forms of the housing stock are strongly segregated, e.g. where there are closed Wilhelminian-style districts or those that consist almost exclusively of prefabricated or social buildings ( large housing estates and satellite towns ). In Germany, for example, this is particularly true of Rostock , Erfurt and Potsdam , which were identified in a study from 2018 as large cities with the highest social segregation. An active housing construction policy, on the other hand, has a dampening effect, as has been practiced in Vienna in the form of municipal housing since the First World War, which is why many cities have been based on the Vienna model since around 1990. The destruction of the Second World War also had a compensatory effect in a certain way, since (partially) destroyed and rebuilt cities such as Mainz have heterogeneous structural forms on a small scale and, for example, attractive Wilhelminian-style buildings alternate with rather simple buildings from the post-war period within a street, which is also reflected in the rental prices and the Reflected the resident structure.
Property bearers can be population groups, residential buildings, commercial facilities, social infrastructure facilities and the like. Residential segregation describes the segregation of different population groups according to their place of residence. As a rule, segregation of subsets of a population is distinguished according to the following status characteristics:
- Segregation according to demographic status
- Segregation according to social status and / or
- Segregation by ethnic / religious affiliation
of the respective population group. The extent of the segregation is strongly dependent on the selected sub-units of the examination area and the characteristics.
There are three concepts for measuring segregation:
- Unequal distribution measures such as segregation, dissimilarity index , Gini coefficient and the Theil index ,
- Measures of exposure ( interaction / isolation between groups) and
- Urban dimensions ( clustering ).
Measurement of inequality
When describing the segregation of different population groups, the degree of inequality is assigned at the same time, ie a group that differs greatly from others is also assigned to a particularly sharply delimited area.
There are various measures to represent spatial inequality. The dissimilarity index and the segregation index are widespread. The former is used to compare the distribution of two population groups with one another, while the segregation index measures the distribution of a population group in relation to the total population. Both indicators can assume values between 0 (uniform distribution) and 100 (complete spatial segregation / dissimilarity).
For the calculation of the dissimilarity index of population groups A and B, the difference between the share of group A in the totality of A and the share of B in the totality of B is formed for each spatial unit. The amounts of these differences add up over all spatial units and then halve the dissimilarity index (ID) between A and B.
The segregation index (IS) is calculated in the same way using the sum of the share differences between group A in the i th spatial unit and the total population G minus the considered group A.
where: = total population - considered group A
Both indicator values can be interpreted as the percentage of the observed groups that would have to move in order to achieve an equal distribution.
The spatial distributions of the population groups segregated according to the individual status characteristics overlap. Investigations of Murdie (1969) showed that indicate the different concepts in the patterns of segregation after the three status characteristics basic types of urban structures urban structure models of the Chicago School , respectively.
- The segregation according to social status shows a sectoral structure.
- Segregation according to family status shows a ring-shaped structure.
- Ethnic segregation has a multi-core structure.
These basic socio-spatial dimensions were examined for various large cities and Murdie's statements were confirmed.
In view of the fact that the strong spatial unequal distribution of individual groups often goes hand in hand with increased crime rates and accelerated urban decay (through disinvestment ) and that the image of the city as a whole suffers, various desegregation strategies are being developed. However, one should warn against the 'ecological fallacy': Segregation does not have to be responsible for higher crime rates in an area (according to the context). They can simply arise from the addition of criminal acts by people that would be conspicuous everywhere - in which case, reducing segregation would not reduce crime.
The richest and the poorest are always the most segregated in a city: "The rich live where they want - the poor where they have to." The poorest usually include immigrants, whose spatial segregation is particularly often criticized without at the same time would be told how to reduce it.
In simple terms, stronger social control and a more pronounced territorial binding of an existing resident structure should ensure that the negative effects of segregation are limited. In addition to general improvements in the living environment, legislation that protects the interests of the tenant (preventing or limiting gentrification ), rent subsidies (e.g. housing benefit), opening clauses in the social housing stock , increased school integration of foreign-language minorities and various anti-discrimination initiatives are associated with this. In addition to the availability of the necessary financial resources, it is essential for the success of such strategies that there is a complementary societal consensus on how to deal with minorities.
- Gerhard Braun, Heribert Müller: Analysis of inner-city migrations - theories and methods of social and factor ecology. In: Eckart Elsner (ed.): Demographic planning information. Theory and technology. Kulturbuch-Verlag, Berlin 1979, pp. 239-277.
- Rauf Ceylan : Ethnic Colonies. Origin, function and change using the example of Turkish mosques and cafes. VS - Verlag für Sozialwissenschaften, Wiesbaden 2006, ISBN 3-531-15258-0 (Also: Bochum, University, dissertation, 2006).
- Jan Dohnke, Antje Seidel-Schulze, Hartmut Häußermann : Segregation, concentration, polarization - socio-spatial development in German cities 2007–2009 (= Difu-Impulse. Vol. 4, 2012). Difu, Berlin 2012, ISBN 978-3-88118-507-3 .
- Jürgen Friedrichs : City Analysis. Social and spatial organization of society (= Rororo study 104 social science ). Rowohlt, Reinbek near Hamburg 1977, ISBN 3-499-21104-1 .
- Jürgen Friedrichs: Urban Sociology. Leske + Budrich, Opladen 1995, ISBN 3-8100-1409-5 .
- Tammo Grabbert: Shrinking Cities and Segregation. A comparative study on Leipzig and Essen. wvb - Wissenschaftlicher Verlag, Berlin 2008, ISBN 978-3-86573-338-2 .
- Hartmut Häußermann, Walter Siebel : urban sociology. An introduction. Campus-Verlag, Frankfurt am Main u. a. 2004, ISBN 3-593-37497-8 .
- Roderick J. Harrison, Daniel H. Weinberg: Racial and ethnic residential segregation in 1990. US Bureau of the Census, Washington DC 1992.
- Annette Harth, Gitta Scheller, Wulf Tessin (eds.): City and social inequality. Leske + Budrich, Opladen 2000, ISBN 3-8100-2657-3 (essays by Friedrichs, Dangschat, Häußermann and Siebel).
- Institute for State and Urban Development Research and Construction of the State of North Rhine-Westphalia a. a. (Ed.): Social space analysis. Social, ethnic and demographic segregation in the cities of North Rhine-Westphalia (= Institute for State and Urban Development Research and Construction of the State of North Rhine-Westphalia. ILS NRW. 201). ILS NRW, Dortmund 2006, ISBN 3-8176-6201-7 .
- Elisabeth Lichtenberger : urban geography. Volume 1: Terms, concepts, models, processes. Teubner, Stuttgart a. a. 1986, ISBN 3-519-03424-7 .
- Friedhelm Steffens: Integration and Segregation Patterns of Turkish Migrants. People in the field of tension between tradition and modernity. The Ford employees in Cologne (= series of publications studies on migration research. Vol. 9). Dr. Kovač, Hamburg 2008, ISBN 978-3-8300-3736-1 (also: Hagen, Fernuniversität, dissertation, 2008).
- Günter Thieme: Segregation. In: Helmuth Köck (Hrsg.): Handbuch des Geographieunterrichts. Volume 2: Dieter Börsch (Ed.): Population and space. Aulis Verlag Deubner, Cologne 1993, ISBN 3-7614-1484-6 , pp. 167-171.
- Ethnic segregation and intercultural urban development in the Ruhr area at westfalen-regional.de
- Student, cross-media project on segregation at the University of Bremen
- The privatization of public space in the USA. (PDF) In: Raummuster - Plannerstoff. Festschrift for Fritz Kastner on his 85th birthday. Institute for Spatial Planning and Rural Reorganization of BOKU, Vienna: 29-39. Vienna. G. Weber G., 1999, accessed April 5, 2008 .
- Marcel Helbig and Stefanie Jähnen: How fragile is the social architecture of our cities? Trends and analyzes of segregation in 74 German cities . Berlin, 2018 (PDF, 207 pages, 2.4 MB).
- The dissimilarity index corresponds to the Hoover unequal distribution .
- The Gini coefficient is based on the Lorenz curve .
- umgabe.de - The online unequal distribution calculator also determines a Hoover unequal distribution of 73.6 directly, i.e. i.e. without the need to determine percentages. (Some other information from the calculator applies to income or wealth distributions and is not relevant to this example.)
- Annette Harth, Ulfert Herlyn, Gitta Scheller: Social segregation in East German cities. Past and future development trends. in: From politics and contemporary history . Supplement to the weekly newspaper Das Parlament . B 5/99. January 29, 1999. p. 38 with reference to: Homer Hoyt: One Hundred Years of Land Values in Chicago. New York 1970.