Andrey Veykher National Research University «Higher School оf Economics» in St-Petersburg, Russia The representative study of households based on the data of individual interviewing
Questions raised by clients of surveys 1) How many households with two children of school or preschool age are there in the city? 2) What is the percentage of single-livings person and couple households? 3) How are the households distributed by amount of total income? 4) What part of the households with total month income between $ 2,000 and $ 4,000 have real estate in the countryside and haven't car? 2ESRA - Lausanne
Methodological problem If the units of representative survey were individuals, how to recalculate the percentages, means, another parameters of distributions of individuals into the same parameters of distributions for units – households?
How many children are in your family? Survey of households Survey of individuals the number of households with 2 or 3 children – possible object of social assistance the number of people who live in the households with 2 or 3 children – data with no practical value 4ESRA - Lausanne
Differences of individuals and households distributions single-living couple (2 adult) in population (individuals) 20%42% in households Data source: survey company “Crona Corsinto Ltd” (St-Petersburg, 2009) 5ESRA - Lausanne
Differences of individuals and households distributions single-living couple (2 adult) in population20%42% in households38%40% Data source: survey company “Crona Corsinto Ltd” (St-Petersburg, 2009) 6ESRA - Lausanne
Algorithm as a part of complex Complex was created by survey company “Crona Corsinto” (© 2001): 4 steps stratified sample with quota sampling “age + gender” at the end stage Interview “face-to-face by houses adjoining survey” Algorithm of recalculating the data of population into the data of households Method of external validity of sampling and implementing data collection ESRA - Lausanne
Basic assumption Households of M members of the target populations age are represented in the probability sample at M times more than households of single-living.
where: X j – percentage of households with feature J; I – number of adult household members, I = 1,2,3…; n ij – number of respondents in the survey, who have feature J and belong to the household with I adult people 9ESRA - Lausanne
Steps of calculation - start Scale values in different distributions Adult person in household Sum No children (individuals) No children (households) One child (individuals) One child (households) Two children (individuals) Two children (households) 10ESRA - Lausanne
1 st steps of calculation – weight = 1 Scale values in different distributions Adult person in household Sum 1234 No children (individuals) No children (households) 1212 One child (individuals) One child (households) 2 Two children (individuals) Two children (households) 1 11ESRA - Lausanne
2 nd steps – weight = 0.5 Scale values in different distributions Adult person in household Sum 1234 No children (individuals) No children (households) One child (individuals) One child (households) 27 Two children (individuals) Two children (households) 12 12ESRA - Lausanne
3 rd steps – weight = 0.33 Scale values in different distributions Adult person in household Sum 1234 No children (individuals) No children (households) One child (individuals) One child (households) 276 Two children (individuals) Two children (households) ESRA - Lausanne
4 th steps – weight = 0.25 Scale values in different distributions Adult person in household Sum 1234 No children (individuals) No children (households) One child (individuals) One child (households) 2761 Two children (individuals) Two children (households) ESRA - Lausanne
Steps of calculation - finish Scale values in different distributions Adult person in household Sum No children (individuals) No children (households) One child (individuals) One child (households) Two children (individuals) Two children (households) ESRA - Lausanne
What is the household limits? ESRA - Lausanne In St-Petersburg: - more than 10% citizens live in another place than they are registered as electors; - 40% persons older after 70 live separately of adult children, but they have common family budget; - more often we observe how families of high middle class have two or three flats, where live older children without economical independence.
Condition and consequence of algorithm implement ESRA - Lausanne Condition – special question in survey questionnaires "How many people in your household who is over 18 years /or another limit of target population/?" Consequence – obtaining additional data for external validity for estimation of sample and data collection quality.
Result of real project ESRA - Lausanne In Saint-Petersburg (2007) the deviation of calculated from survey data number of children thousands – from statistics – 742 thousands (error - 1,3%) allows us to say that proportions of households distributions by number of children correspond to reality.
Conclusions: ESRA - Lausanne There are possibilities to obtain many answers about household by more cheap survey of individuals. Effective and attractive for clients control quality of sampling and data collection implementing is possible by estimation external data and the result of matrix sequential calculations on survey data about households.
Thank you for your attention! NIU HSE in St-Petersburg ESRA - Lausanne