Introduction to the KLoWF

Introduces overall content of the KLoWF,
survey areas and methods

homeHomeIntroductionSampling Design of the KLoWF

Subjects of the survey

Households and female household members within the households which have women aged from 19 to 64

Household refers to a unit of living in which one or more persons share their livelihoods, such as cooking and sleeping.

Household members refer to all family members and their relatives/in-laws living in the household selected for the survey.

Population

Population of KLoWF includes households which exist in the territory of the Republic of Korea at the time of the survey of 2007.

Residences or dwelling places where the survey is practically impossible are excluded from the population. Such examples are facilities for national troops and combat police, jails, juvenile reformatories, detention centers at police stations, barracks for foreign military forces, and residences of foreigners who are excluded from the survey.

Sampling frame

About 260,000 enumeration districts (EDs) based on the results of 2005 Population and Housing Census are used as a basic sampling frame for selecting the primary sampling unit(PSU).

EDs from facilities and island areas (except for Jeju Island) are excluded from the EDs used as the sampling frame for selecting the primary sampling unit(PSU).

Method of selecting the primary sampling unit(PSU)

To select EDs for the primary sampling unit(PSU), the enumeration districts (EDs) of the results of 2005 Population and Housing Census are arranged based on the criteria for stratification.

Designation of stratification variables
1. Criteria for stratifying EDs: degree of urbanization, proportion of workers by industry, and proportion of households by housing type for the EDs
2. Stratification variables added in consideration of purposes and content of KLoWF: household distribution by number of household members, age of the head of household, and sex of the head of household

1,700 EDs are selected by applying the 'probability proportional to size systematic sampling.' When distributing the EDs selected from each region, the method of simple proportional distribution is not used but the method of distributing the EDs is used according to the square root proportion of the EDs by region.

In order to replace sample EDs which are impossible to survey due to dissolution or development of relevant EDs, 300 preliminary sample EDs are separately selected in the same manner.

Method of selecting the secondary sampling unit(PSU)

The secondary sampling unit (SSU) is a household in an ED selected as PSU.

Households to be surveyed are selected by systematic sampling from the finally selected 1700 households as PSU

About 5 households are selected by systematic sampling from one sampling ED to examine 10,000 female household members, which is the ultimate goal. In the actual survey, 4 to 7 households were selected per ED.

If there is no female household member aged between 19 and 64 in a household selected by systematic sampling as a sample household, then a household in the sub-level I is selected as a household to be surveyed. If no woman aged from 19 to 64 exists even in the sub-level household, the household at a level lower than the sub-level is selected as a household to be surveyed.

Replacement of sample EDs

As the EDs used in selecting the final sample households were based on 2005 Population and Housing Census, there were not enough information of the households to be surveyed in 2006. In other words, because of natural disasters, development or redevelopment of new towns, sample households did not exist in the EDs in 2006.

If there are not enough samples because the survey is impossible or many households refuse to answer, sample EDs are replaced with EDs which have the same characteristics as the sample EDs. In the actual survey, they were replaced with the EDs closest to administrative districts.

Replacement of sample households

If the household selected for a sample has no address, if there are no household members living in the selected household, or if the household refuse to answer, record the reasons for the impossible survey and then select other households for samples according to the principle of replacing samples,

The principle of replacing samples is to replace with the household which has the residence number next to the residence number given to the sample household in the list of households within the ED.

Selection of final respondents

Final respondents of KLoWF were selected from all women aged from 19 to 64 among the household members of the sample households who lived in the sample EDs.

As a result of the actual survey, a total of 9,997 women were surveyed from a total of 9,068 households.