Official name of the survey/data source:
Income and Property Distribution Survey

LIS name:
Norwegian Income Survey - 1986

Administrative unit responsible for the survey:
Central Bureau of Statistics.

Funding for the Norwegian Income Survey is provided for by the budget of the Central Statistical Office. Copies of the original codebook and other documentation can be obtained from the Central Statistical Office - Section for Income and Wage Statistics at the above address. The principle users of the data collected in this survey are research institutions, government departments, etc..

The Norwegian Income Survey was set up in 1982. The survey is conducted annually. The main focus of the survey is to provide information about the structure and distribution of income and property for households and individuals.

The process of data collection for the 1986 Income Survey was begun in August 1987 and was completed in November 1987; the information being collected retrospectively for 1986.

Use of this data is restricted. Certain legal requirements must be met (i.e. anonymity of individuals and an official permit for the data recipient to establish a data register).

A bibliography of the most important publications based on the Norwegian Income Survey is provided in the bibliography in Section M. Also included in the bibliography in Section M is a list of available user documentation for the Norwegian Income Survey.

B POPULATION AND SAMPLE SIZE, SAMPLING METHODS back

The basic sample is a two-stage sample with stratification in the first stage and one primary sampling unit (psu) selected from each stratum. The construction of the psu is based on the municipalities of Norway. Those with less than 3,000 inhabitants according to the census in 1970 are collapsed such that every psu has at least 3,000 inhabitants. Before selection the primary sampling units are stratified according to size, region and type of economic activity. The large cities form their own strata and are so-called self- representing. In each of the other strata one psu is selected with a probability proportional to the size according to the population census 1970. The selected primary sampling units become the primary areas and are used repeatedly year after year, preserving the continuity and investment of a core of trained interviewers and of established frames. In the second stage a sample of persons or households is selected from the Central Register of Persons.

In many aspects the sample is designed in the same way as similar surveys are designed in other statistical agencies. Only the selection in the second stage differs from what is done elsewhere, because of the existence of detailed registers of persons in Norway.

The sampling frame includes the total population of household heads. People living in institutions, such as prisons, old people's homes, wards, etc. (ca. 2% of the population), have been excluded from the survey. If a person is considered to belong to the household (i.e. having a common board) he/she is included.

The total number of units for which the sample was selected was 3,151,752 (i.e. the 1986 number of persons in Norway, older than 15). A total number of 14,271 persons (weighted: 4,118,852) and 4,975 households (weighted 1,708,345) were actually surveyed. About 2/3 was selected for a panel, first introduced in 1982. This is the sample size that was made available to the Luxembourg Income Study.

C. MEASURES OF DATA QUALITY back

The overall non-response rate to the Norwegian Income Survey is 22%. As only household composition was actually asked, administrative records (Central Population Register) were used to establish household composition in case of non-response. Thus there are no missing data for the Norwegian Income Survey. Only administrative records were used to collect income data. Child benefits have been estimated.

The survey had to deal with the problem that, by using administrative records to collect income data, the survey does not contain information on the income from the informal sector. Furthermore, as estimates are based on tax assessments and not on actual market value, the value of the real capital is supposed to be understated. There is also no information available on the household members labor participation (i.e. there is no information about the relationship between hours worked and received wages and salaries).

D. DATA COLLECTION AND ACQUISITION back

Data collection is almost exclusively done by face-to-face interviews, with the use of optical readable forms (The Norwegian Income Survey was also part of the Level of Living Survey). All other data, such as all income data, was collected from public registers. The interview was organized by individuals (age > 15 years). The participation in the survey was voluntary. One person was allowed to answer for all the other members of the household.

E. WEIGHTING PROCEDURES back

The Norwegian Income Survey is weighted to report population estimates, etc.. The weighting did not help to adjust for missing data or other nonsampling errors related to income. The sum of survey weights is equal to the total number of units in the sampling frame.

However, estimates derived from the sample are not representative of the total population defined by the sampling frame, as the survey does not include persons living in institutions (ca. 50,000 persons).

F. DETERMINATION OF SURVEY UNIT MEMBERSHIP back

The basic units of aggregation of the Norwegian Income Survey are persons and households. All persons which the respondent considers to belong to the household is included. In most cases they also include household members being temporarily absent (Children, students away from home or attending school or other educational institutions, husbands away from home at work or on military duty, etc.). The household head was defined as the person having the highest gross income. In case of doubt it is the oldest person in the household.

G. CHILDREN AND SPOUSES back

In the Norwegian Income Survey all persons under the age of 17 are considered to be children. Children in the household that are not the children of the head or spouse can be distinguished by the use of the family number. Spouses are defined according to the administrative records and the tax returns.

H. AVAILABILITY OF BASIC SOCIAL AND DEMOGRAPHIC INFORMATION back

In Table 7.2 are summarized the basic social and demographic information which is available in the Norwegian Income Survey.

Table 7.2
Basic Social and Demographic Information

I. AVAILABILITY OF LABOUR MARKET INFORMATION back 

Labor force status information is available for this survey. No groups were excluded at the time of interview through filter questions relating to the employment status of the respondent, although only income recipients were requested to provide answers to the income schedule. The labor market information which is available in the survey is summarized in Table 7.3.

Table 7.3:
Labor Market Information

J. AVAILABILITY OF GEOGRAPHIC INFORMATION back

The size of the municipality is available for each household.

K. SOURCES AND AMOUNTS OF CASH INCOME back

To record the sources and amounts of income received a reference period of one year was used. The amounts received are actual amounts. The sources and amounts of income are recorded for every individual household member. Income from tax returns and other income (transfers, etc.) are collected from administrative registers.

L. TAXES back

Taxation information is available for this survey.

M. BIBLIOGRAPHY OF MAIN PUBLICATIONS back

Norwegian Official Statistics: "Income and Property Statistics" (Biannual).

Norwegian Official Statistics: "Wages, Salaries and Income" (Biannual).