Czech Experience with the Tracing in EU-SILC Simona Měřinská Household Surveys Department Workshop on best practices for EU-SILC Warsaw, Poland, October 2018

TRACING in EU-SILC The specificity of EU-SILC survey is to trace respondents while they move. The tracing of respondents is a challenging task. If a respondent (or the entire household) from the original selected dwelling moves to another dwelling, municipality or even another region within the Czech Republic, the tracing process is initiated and the „investigation“ of the person is carried out. It requires: pretty tough logistics prompt reactions in the fieldwork good management of the whole process (interviewers have to cooperate with their regional coordinators and those have to cooperate between themselves among other regions)

It involves: moves between regions across the whole country splits off into more different addresses It is necessary: to find out appropriate information to trace panel persons from the selected household to interview them at their new address (before the end of the fieldwork period) Out of scope: persons moving abroad or to a collective household or institution (eg. prisons, hospices, retirement homes) are not considered to be traced.

Tracing Application for CZ-SILC at CZSO we created a dedicated logistics application for tracing of respondents it enables standard CAPI interviews also for movers, including across-regions mobility it allows to transfer all the data (information obtained from previous waves so far) with the moved people easily to a new address, then create a new identification for them and to survey them at the new address where they currently live.  Monitoring of the tracing process

SILC tracing data flows Central data repository The concerned new region coordinator receives notification and data move information file, processes it and assigns the new address to one of their interviewers Interviewer records the data about the move, and data move information file is sent to central repository by eDomSet module Regional coordinator receives notification about the move and handles the case If the new known address is in a different region, coordinator assigns new region New region into which the respondent moves Import file with new case data about moved respondents Region from where the move is taking place

Czech tracing APPLICATION List of all cases in given region – overview of all moved panel persons A simple form to be filled in about the moved household or each person individually, when the new address is known or even unknown

TIME SERIES Number of cases of moved households within Czech SILC survey during past 10 years varies around 160 and is rather low (only about 2 – 3 % of the sample), which means that moving is relatively rare in the country.

Number of moved persons in SILC 2017: somewhere within the country abroad to an institution or collective household no information Number of moved persons in SILC 2017: Panel person has moved another private HH within CR – 404 abroad – 42 institution – 31 not identified – 203

TRACING PROCESS successfully interviewed 266 address found out 294 not interviewed at new address 28 address found out 294 address not found out 110 to be traced 404

ANALYSIS OF DATA Who are the people who slip through our fingers? Those we can not find and interview again were already our respondents in the previous wave and unlike non-respondents we have a lot of information about them from last year. What is the impact of tracing process on our final SILC indicators? We have calculated the impact on the key published indicators removing all the moved people from the file, re-weighted it and tried to find out what is the effect. How about the comparison between traced respondents and not traced people? We have examined the characteristics of those who moved, which of them we can successfully trace and how many people are willing to further cooperate and how many people refuse on the new address.

NEW ADDRESS NOT KNOWN (NON-TRACED) Age 80 % of non-traced people is at age 0-34 years (i.e. families with little children and also young individuals) Education 60 % of them have secondary education with or without „leaving exam“ Economic activity They are most often full-time employees (43.6%) and students (12.7%) characteristics of panel persons we were not able to trace Housing They live mostly in their own homes or privately owned apartments Size of flat 60% of them live in larger flats with an area of 60-100 m2 Net income of the person They are mostly middle-income people but also those without any income

NEW ADDRESS KNOWN (TRACING SUCCEEDED) Age Half of the successfully traced people is at age 25-44 years plus 28.2% are pre-school children (i.e. young families) Education 44.4 % of them have secondary education, but also 15.1 % have tertiary education Economic activity Half of them are full-time employees characteristics of panel persons who were visited on their new address & interviewed again Housing They often live in rented flats (47.4 %) Size of flat 60 % of them live in medium-sized flats with area of 40-80 m2 Net income of the person Their income is only slightly higher than income of non-traced

TRACING INVOLVES PROBLEMS Tady ještě něco vymyslím k tomu srovnání nedohledaní, úspěšně došetření a odmítači na nové adrese TRACING INVOLVES PROBLEMS When one selected household is split into 2 households, each person moves to a different address elsewhere (eg. divorced couples, adult children become independent and move from their parents etc.) and when one of the panel persons even refuses to participate in the survey. successfully interviewed new address known not interviewed (refusals, non-contacts, ill)

KEY PUBLISHED INDICATORS FROM CZ-SILC 172 173 CZK Average yearly income per person in CR 134 334 CZK Poverty threshold 9.1 % At-risk-of-poverty rate (AROP)

Průměrný roční příjem na osobu v ČR Průměr hodnoty ukazatele Medián ukazatele Variační koeficient ukazatele 1. decil ukazatele 2. decil ukazatele 3. decil ukazatele 4. decil ukazatele 5. decil ukazatele 6. decil ukazatele 7. decil ukazatele 8. decil ukazatele 9. decil ukazatele Official 172 173 159 700 58,9 99 786 122 676 134 688 146 358 175 370 195 842 230 103 287 847 Without moved 171 893 159 521 57,8 99 158 122 400 134 502 146 180 175 200 195 151 229 680 287 531 ratio 99,8 99,9 98,1 99,4 99,6 Comparison of key indicators without moved panel persons prepare better tables! Poverty rate 60% official Without moved ratio Men 7,6 7,4 97,4 Women 10,7 10,8 100,9 Under 18 years 11,6 11,7 65+ 10,9 101,9 Working 3,5 3,6 102,9 Unemployed 48,6 47 96,7 Retired 11 without children 8,7 8,8 101,1 With children 9,6 9,5 99,0 1 adult with 1+ children 31,4 32,2 102,5 EU EQPRIJ =EU_PRIJ/EJ   Poverty60 Povert rate Official 134 334 9,1 without moved 134 218 ratio 99,9 100,0 The results are statistically identical. Everything is within the confidence interval. Even if we choose a more detailed sorting of people (eg. unemployed or single-parent with children), we still come within the sample error because these specific groups have a wider confidence interval.

CONCLUSIONS

In Czech conditions on relatively small sample I may say… Respondents who have moved from the original selected household to a new address have no such characteristics to change the results, so they do not have any effect on our outputs and key indicators. Excluding these people has no impact on published results. Obviously, it can not be taken in absolute terms, but in the context that all statistical results are estimates within a certain confidence interval. All the effort that our national Statistical Office devotes to the methodology of tracing and processing of longitudinal data and all the vigorous effort that our field workers spend on managing the required processes every year is essentially an inefficient capacity burden –”unnecessary luxury”. It is a challenge to do something about it, but under Regulation the tracing of panel persons within EU-SILC survey is still obligatory.

Ready for discussion! Contact us at: www.czso.cz simona.merinska@czso.cz