Germany 1984 - Documentation

Germany 1984 - Documentation Table of Contents A. GENERAL INFORMATION B. POPULATION AND SAMPLE SIZE, SAMPLING METHODS C. MEASURES OF DATA QUALITY D. DATA COLLECTION AND ACQUISITION E. WEIGHTING PROCEDURES F. DETERMINATION OF SURVEY UNIT MEMBERSHIP G. CHILDREN AND SPOUSES H. AVAILABILITY OF BASIC SOCIAL AND DEMOGRAPHIC INFORMATION I. AVAILABILITY OF LABOUR MARKET INFORMATION J. AVAILABILITY OF GEOGRAPHIC INFORMATION K. SOURCES AND AMOUNTS OF CASH INCOME L. TAXES M. BIBLIOGRAPHY OF MAIN PUBLICATIONS BASED ON THE CSP PANEL A. GENERAL INFORMATION back Official name of the survey/data source: Sozio-ökonomisches Panel (German Socio-Economic Panel Study) Administrative unit responsible for survey: German Institute for Economic Research (Deutsches Institut für Wirtschaftsforschung, DIW) Koenigin-Luise Straße 5 Phone: 0049-30-82991283 Fax: 0049-30-82991200 Funding for the German Socio-Economic Panel Study survey is provided for by the German National Science Foundation (Deutsche Forschungsgemeinschaft/ DFG,Bonn). Copies of the original codebook and other documentation can be obtained from the German Institute for Economic Research (Deutsches Institut für Wirtschaftsforschung, DIW) at the address above. For additional information to that provided here on various aspects of the survey the following people can be contacted: Sample Design: Dr. Gert Wagner/ Dr. Ulrich Rendtel

Phone: 0049-30-82991 290/300 Data collection process: Juergen Schupp/Elke Holst Phone: 0049-30-82991 238/281 Demographic Information: Joachim Frick Phone: 0049-30-82991 279 Income Information: Dr. Johannes Schwarze/ Dr. Gert Wagner Phone: 0049-30-82991 287/290 Editing and Survey Processing: Peter Krause/ Dr. Rainer Pischner Phone: 0049-30-82991 690/319 The principle users of the data collected in this survey are members of the "Special Collaborative Programme 3" (SfB 3) and members of the "German Institute for Economic Research" (DIW) and other interested researchers. The first year in which the SOEP was conducted was 1984, and was first made available as microdata in 1984. Field work for the seventh wave of the panel was begun in 1990. The main purpose of the survey is to provide microanalyses of the dynamics of individual welfare, and to evaluate the social impact of government social policy. A comprehensive concept of individual welfare is used in this survey, which includes economic, social and political aspects of well-being, both at the level of objective observable characteristics and at the subjective level of aspiration, perception, attitudes and satisfaction. The process of data collection (i.e. field work) for the first wave of LIS data was begun in February 1984 and completed in October 1984. The public has access to the data under the condition that a contract be entered into between the recipient of the data and the German Institute for Economic Research (DIW). The SOEP microdata have been made available to the

Luxembourg Income Study Project under the same conditions. A bibliography of the most important publications based on the SOEP data is provided in section N. Also included in the bibliography in section N is a list of the user documentation for the SOEP data. B. POPULATION AND SAMPLE SIZE, SAMPLING METHODS back The sampling design for the survey is based on the so-called ADM concept (Study Group of German Market Research Institutes). The final stage sampling frame which was used was the list of registered voters in the German Federal Government Election of 1980. Information from the 1970 population census was used to convert eligible voters per voting district into households. In addition, a subsample which included the main groups of guest workers (Spanish, Italian, Greek, Turkish, Yugoslavian) was selected. This was based on an area sample which was drawn separately for each nationality from regional administrative registers. The sampling units are both housing units and individuals. People living in institutions or other group situations are included in the survey in those cases where there are no extraordinary difficulties in obtaining an interview; e.g. persons living in homes for the elderly, dormitories, etc. Each sample member who moves into such an institution is followed in the panel. Military personnel living in military housing are excluded from the sample. However, military personnel living with their families are included, but it is not possible to identify them separately. These individuals are included in the occupational category of "judge, civil servant or professional soldiers." Once the sample was selected from the sampling frame, all sampling units were eligible for interview. 1. The Sample Design The SOEP employs a two stage stratified sampling design. In the first stage a sample proportional to household size was selected. For the second stage a random route sampling point (voting district) was used. Both stages result in equal selection probabilities for households. There were different selection probabilities for each group. Five important groups of foreign nationals (citizens of Turkey, Italy, Spain, Yugoslavia, Greece) were over-sampled in order to allow for sparate analysis later. There were a total of 26,019,000 units (households) in the population from which the SOEC sample was selected. The total number of respondents who were actually surveyed was 5,322. When weighted this amounts to 25,753 cases. Because of missing income data a number of households had to be excluded. The sample that was made available for the LIS database was comprised of 5,174 cases, of which LIS was able to make available to its users all 5,174 cases. 599 households in the the SOEP sample were not interviewed because they were found to be ineligible at the time of the interview. All geographic areas in the country were included in the sample design. Estimates of sampling variability (standard errors) have been computed for this survey. Available estimates are reported in: User Handbook Section K.4 U. Rendtel (1990) Hochrechnung und Stichprobenfehler in Panelerhebungen, SfB3 Arbeitspapier No. 321 Frankfurt/Mannheim and:

U. Rendtel (1988), Population Estimates and the RepresentativeCharacter of the Data (English translation of an article in: Krupp/Schupp (Eds.), Lebenslagen im Wandel 1987, Frankfurt) C. MEASURES OF DATA QUALITY back 1. Item and Group Nonresponse Rates The overall non-response rate for the first wave of the SOEP survey was 38.3%, and for the second wave it was 11.1% (of those who participated in the first wave). The non-response rates of foreigners within the survey are available. These are reported in Table 4.1. Table 4.1 Non-Response Rates of Foreigners within the Survey Subgroup % Wave 1 SOEP: Foreigners 29.9-35.3 Wave 2 SOEP: Foreigners 17.4 2. Reporting and Under-Reporting and Income Data Quality An evaluation of the quality of the income data has been made by comparing the SOEP data with income data from other sources (National Income Accounts, Income and Consumer Survey, DIW Calculation). An evaluation of the quality of tax, demographic, wealth, expenditure and other data has also been made. This evaluation resulted in the use of a sample of income tax payers and a sub-sample from the Income and Consumer Survey in order to improve the data which was used for tax simulation models in the SOEP. Internal edits and checks for consistency errors or for data items have been performed. More detailed information can be found in Berntsen, Working Paper No. 291 and in Kassella/ Hochmuth, Working paper No. 299. 3. Data Corrections and Adjustments Adjustments to the original data of the SOEP have been made in order to improve the data quality. New variables were generated in order to supplement the income data and correct for non-plausible values among the different income components. In addition, "hot- decking" was employed in order to correct for item non-response. (See Berentsen, Working Paper no. 291). 4. General Assessment of Income Data Quality Although a number of corrections and adjustments have been made, users of the SOEP data should be aware of the following problems regarding the quality of the income data collected in this survey: 1. A relatively high number of missing values 2. Inconsistent answers 3. The use of different time periods D. DATA COLLECTION AND ACQUISITION back 1. Method of Data Collection

The data was collected via a personal visit by an interviewer. Telephone and mail interviews were used in special cases. Participation in the survey was voluntary and privacy was assured by German privacy laws. The explicit agreement of all household members to participate in the SOEP was required. 2. Structure of the Survey Instrument Four questionnaires were used in the SOEP: 1. Household head schedule 2. Schedule for each individual over 16 3. Schedule for foreigners 4. Address record (in order to follow people through the panel) 3. Survey Respondent Rules For the SOEP a single reference person--usually the head of household--responds to general questions regarding the household as a whole, and the dwelling in particular. Each household member 16 years or over is also interviewed. Members of the original sample are reinterviewed each year as long as they remain within the reference population. Original sample persons are generally followed when they split off and move to other households. Associated persons who move into a sample household are also interviewed. Respondents of the SOEP questionnaire were asked to consult pay records, tax returns, and other documents to help provide the most accurate income information possible. However, it is not known how many respondents used records to help them answer the income or other questions. E. WEIGHTING PROCEDURES back Survey weights have been assigned in the SOEP to each sample case. These weights were assigned in order to adjust for unequal sampling probabilities which were built into the sampling design; both for undercoverage in the first wave, and for differential response rates in subsequent waves. These weighting procedures did not help adjust for missing data or other nonsampling errors related to the income data. The sum of the survey weights is equal to the total number of units in the sampling frame. Estimates derived from the sample are representative of the total population as defined by the sampling frame. F. DETERMINATION OF SURVEY UNIT MEMBERSHIP back Households are housing and economic units, comprised of one or more individuals. Household members need not be related to each other. The basic unit of aggregation which was used in the SOEP was the individual. The overall sampling unit can be divided into subgroups in those situations where several families share the same housing unit. The survey unit head was defined as the person with the best knowledge of household living conditions (not in general the oldest person). Individuals other than the sampling unit head can be identified, and information about the relationship of individuals to the head of household is available. G. CHILDREN AND SPOUSES back

In the SOEP no specific rule is used to define children. However, information on individual relationships to the head of household is available (e.g. own or adopted children). Hence it is possible to identify children--including adult children--of the head. The survey also provides information which allows one to distinguish made between children of the unit head (or spouse), and children of some other household member, or of someone living outside the household. In this survey spouses are not explicitly defined. However, as with children, spouses can be identified through their relationship to the head of household. H. AVAILABILITY OF BASIC SOCIAL AND DEMOGRAPHIC INFORMATION back In Table4.2 are summarized the basic social and demographic information which is available in the SOEP. Table 4.2 Social and Demographic Information Category Available Persons for whom information available Sex Yes All persons Age Yes All persons Year of Birth Yes All persons Relationship to unit head Yes All persons Ethnicity/nationality Yes All persons Race No - Legal marital status or cohabitation Yes All persons Disability status Yes All persons I. AVAILABILITY OF LABOUR MARKET INFORMATION back Labor force status information is available for the month of the interview, and for the previous year. Part-time work was defined as 20-34 hours per week, and full-time work as more than 34 hours per week. This and other labor market information is summarized in Table 4.3. Table 4.3 Labor Market Information Category Available Persons for whom information available Reference period Labour force status Yes All persons Actual, monthly, previous year Hours worked Yes Persons employed at Actual, usual, previous

time of interview month Full/part-time (part-time = 20-34 hours) Type of occupational training/apprenticeship* Yes All persons Actual, previous year Yes All persons Completed training since last year Occupational group Yes Employed, unemployed, looking for a job Industry group Yes Employed, unemployed, looking for a job Actual Actual Worker or professional status Yes All persons Last year, actual Weeks employed last year Yes All persons Last year Duration of unemployment last year Yes All persons Last year Wage/salary income Yes All persons Usual, actual, last year, last month Self employment income Yes(gross/net) All persons Usual, actual, last year, last month J. AVAILABILITY OF GEOGRAPHIC INFORMATION back Because of the high risk of re-identification of respondents, the only geographic information which is available in the SOEP is the Boustedt region. K. SOURCES AND AMOUNTS OF CASH INCOME back Sources and amounts of income are recorded for a monthly and an annual period. Both actual and usual amounts received were recorded. Some income components (such as capital income, child allowances, proprty income, housing benefits, and social assistance benefits) are available only at the household level. L. TAXES back Taxation information is available for the SOEP. Direct taxes have been estimated. M. BIBLIOGRAPHY OF MAIN PUBLICATIONS BASED ON THE CSP PANEL back Autorengemeinschaft Panel (Eds.);1990: Das Sozio-ökonomische Panel für die Bundesrepublik Deutschland nach fünf Wellen. in: Vierteljahreshefte zur Wirtschaftsforschung (Berlin), Heft 2.

Witte, James C.; 1990: The Potential for Comparative Panel Research using data from the U.S. Survey of Income and Programme Participation (SIPP) and the German Socio-Economic Panel(SOEP), DIW working paper, Berlin. Hanefeld, U.; 1987: Das Sozio-ökonomische Panel, Grundlagen und Konzeptionen, Frankfurt/ New York. Hanefeld, U.; 1984: The German Socio-Economic Panel, American Statistical Association, 1984 Proceedings of the Social Statistics Section, Washington D.C. Rendtel, U.; 1987: Methodische Konzepte für die Hochrechnung von Paneldaten. in: Vierteljahreshefte zur Wirtschaftsforschung, Heft 4-1987. Rendtel, U.; 1988: Panelmortalität. in: Vierteljahreshefte zur Wirtschaftsforschung, Heft 1/2-1988. Rendtel, U.; 1989: Über den Einfluß der Panelselektivität auf Längsschnittanalysen. in: Vierteljahreshefte zur Wirtschaftsforschung, Heft 1-1989 Rendtel, U.; 1990: Hochrechnung und Stichprobenfehler in Panelerhebungen, SfB 3 Arbeitspapier Nr. 321. Berntsen, R.; 1989: Einkommensanalyse mit den Daten des Sozio-ökonomischen Panels unter Verwendung von generierten Einkommensdaten, SfB 3 Arbeitspapier Nr. 291. Kassella, T.; U. Hochmuth; 1989: Ein synthetisches Mikrodatenfile des Haushaltssektors für steuerpolitische Simulationen, SfB 3 Arbeitspapier Nr. 299. Berntsen, R; W. Dobroschke-Kohn; 1990: Update 1984/85, Dataset Description Federal Republic of Germany, SfB 3 Documentation. Rendtel, U.; 1988: Population Estimates and Representative Character of the Data, english translation of an article in: Krupp/Schupp (Eds.); 1987: Lebenslagen im Wandel: Daten 1987, Frankfurt. Rendtel, U.; 1990: Teilnahmebereitschaft in Panelstudien: Zwischen Beeinflussung, Vertrauen und sozialer Selektion. in: Kölner Zeitschrift für Soziologie und Sozialpsychologie, Nr.2/1990, pp. 280-299. Sonderforschungsbereich 3 (SfB 3), (ed.): Benutzerhandbuch (user handbook), Frankfurt/M./Mannheim, Berlin. Source: Das Sozio-ökonomische Panel Deutsches Institut für Wirtschaftsforschung Frau Christine Kurka Koenigin- Luise- Straße 5 Phone: 030-82991-283 Fax: 030-82991-200