The Federal Statistical Office and the Statistics Department of the Federal Employment Agency together have developed a project concept to calculate and present geo-referenced rates of SGB II benefits for Germany. A proof of concepts (PoC) has shown the high potential of geo-referenced data.
Results of the statistics on basic security benefits of the Federal Employment Agency and anonymised 2011 Census data form the basis for determining the groups of people entitled to SGB II benefits as a proportion of the population. The reference month is May 2011.
Results can be obtained in a breakdown by the following variable attributes:
- sex (male / female)
- age (under 15, 15 to under 25, 25 to under 55, 55 to under 65)
nationality (German / not German)
Grid maps are used to visualise the rates of SGB II benefits. A rate is shown for each grid cell provided that the following minimum cell frequencies are ensured (for each demographic group such as women, non-Germans, age groups, etc.):
- At least 100 people of the demographic group concerned must have their main place of residence (according to the 2011 Census) in the area of the grid cell (denominator of the rate),
- these must include at least three people entitled to SGB II benefits (numerator of the rate).
The grid width, that is the edge length of a cell, may vary. In the map application, the grid width is 5 km across Germany as a whole. However, additional grid cells of an edge length of 1 km are shown for 25 cities with more than 250,000 inhabitants.
Link to the interactive map: https://arcg.is/0u5SXK
A breakdown of the rates according to the above mentioned variable attributes is not yet possible in the web application due to performance reasons. However, this breakdown is available in a file for download.
Rates of SGB II benefits – Background information
As a standard practice, the Federal Employment Agency has so far determined the rates of SGB II benefits for rural districts and towns not attached to an administrative district. The map application on the rates of SGB II benefits shows the proportions of SGB II recipients in the population by means of geographical grid cells. The rates shown refer to data of May 2011 (confer the „Population“ section).
Methodological notes
Rates of SGB II benefits
The rates of SGB II benefits show the proportions of persons in need of benefits in given groups of the population. “Persons in need” are people who are entitled to receive SGB II benefits. Rates of SGB II benefits are produced for all persons entitled to SGB II benefits (LB) and for the subgroups of “persons entitled to benefits and able to work” (ELB) and “persons entitled to benefits and unable to work” (NEF).
The group of persons entitled to benefits and able to work comprises people who are entitled to unemployment benefit II and, where appropriate, to further benefits pursuant to SGB II. They are at working age (from 15 years to under the standard age limit). The group of persons entitled to benefits and unable to work typically comprises children under 15 years who live together with people entitled to benefits and able to work in a community in need of benefits. They are entitled to a social benefit. The reference variable used to determine the respective rates is the size of the relevant age group of the population living in Germany.
The following three rates are produced:
- SGB II rate = LB / population under 65 years
- ELB rate = ELB / population aged 15 to 65 years
- NEF rate = NEF / population under 15 years
Rates are also calculated for other socio-demographic subgroups (e.g. foreigners). More information on the rates of SGB II benefits is available under "Berechnung von SGB II-Hilfequoten und Bezugsgrößen im SGB II".
Population
The population figures are based on the 2011 Census. The 2011 Census produced population figures for the Federation, Länder and municipalities. These figures were the most important census result. In the framework of the 2011 Census, data related to geographical grids were evaluated for the first time. These data are also used here. As intercensal population updates are not yet produced in a grid-based form, current data at grid level will only be available after the next population census (2021).
More information is available at 2011 Census.
Geographical grids
A grid is a structure which consists of uninterrupted, identical and square-shaped segments. It subdivides a geographical area, e.g. that of Germany, into a set of squares of the same size. The grid width, that is the edge length of a cell, may vary. In the map application, the grid width is 5 km across Germany as a whole. However, additional grid cells with an edge length of 1 km are shown for 25 cities with more than 250,000 inhabitants.
The grid used is based on the coordinate reference system of the Lambert azimuthal equal-area projection with the geodetic system “ETRS89“ (ETRS89-LAEA) the projection centre of which is the point 52°N, 10°E). For clear identification of a grid cell, a cell code is used which consists of the cell size and the coordinates of the bottom left corner in the ETRS89-LAEA reference system (example: 1kmN2684E4334 = grid cell with a side length of 1 km).
Geocoding of addresses
To be able to allocate the "variable carriers" to geographical grid cells, the coordinates associated with the addresses of their places of residence are determined using geo-referenced basic data. The reference data are taken from the “Geocoded addresses (GA)” data set of the Federal Agency for Cartography and Geodesy (BKG). Further information is available at https://gdz.bkg.bund.de/. Based on the determined coordinates, the values of grid cells with any edge length can be added up. Regarding borderland regions, all grid cells are shown which are located at least in part in the German territory. However, the data for these grid cells only relate to the German territory.
Some address information cannot be precisely allocated due to different spellings or spelling errors in the source data. For roughly 150,000 people entitled to SGB II benefits (about 2%), valid information is only available for the post code and place. In those cases, it is not possible to determine the precise location within 1-km or 5-km grid cells. For this reason, these cases were not taken into account in the map application. Some administrative districts are more affected by this problem than other districts. This is why the rates of SGB II benefits are underestimated in the grid cells of these districts. The layer on “Kreise mit den Anteilen ungenauer Adressangaben“ shows, based on categories, the cases not taken into account as a proportion of all people entitled to SGB II benefits of the given districts. This allows the extent of distortion to be assessed in the areas concerned.
Calculation of rates
A meaningful rate can only be obtained if the denominator is sufficiently large. Otherwise the rates would give the impression of a higher accuracy than that of the basic figures used (see DIN 55 301: 1978-09 “Gestaltung statistischer Tabellen“). As a matter of fact, the rate of benefits is calculated for a grid cell only if the reference population for a given variable attribute comprises not less than 100 people. Grid cells which do not fulfil this requirement are highlighted in grey.
Confidentiality
The population data in the denominator are kept confidential using the so-called "SAFE procedure" of the statistical offices of the Federation and the Länder, which is a data perturbation method. See Nutzer-Kurzinformation zu SAFE for more information.
The SAFE procedure is applied before the benefit rates are calculated. This means that grid cells may have 100 inhabitants before the confidentiality procedure is applied and less than 100 inhabitants afterwards - and vice versa. Whether or not a benefit rate is calculated for a given cell depends on the relevant results (see above). Analyses have shown that such deviations occur very rarely and therefore are negligible.
To safeguard statistical confidentiality, the so-called cell suppression method is used in order not to disclose the number of people entitled to SGB II benefits. If a grid cell contains only one or two persons entitled to benefits, the rate of benefits is not shown for this cell. See Regeln der statistischen Geheimhaltung for more information.