Measuring Migration: Best Practices in Censuses and Household Surveys

1. Measuring Migration: Best Practices in Censuses and Household Surveys Gero Carletto Carlo Azzarri

2. Background • Migration policy research hampered by availability of data • Definitions and measurements of migration varies across and within countries (from ≠ sources), and overtime • Best practices? • Lack of consensus • Who is an international migrant? • What type of migration?

3. What type of migration? • Flow vs. Stock • Immigrant vs emigrant (net migration) • Permanent/L-T vs. temporary/S-T • Circular, returnees • Internal • Undocumented/irregular • International migrants vs. international migration (multiple moves)  Different definitions/dimensions, different sources

4. Outline • Concepts and definitions • Data sources • Sampling and survey options • Questionnaire contents/design • Conclusions and next steps

5. Concepts • (Change in) Place of usual residence • Time/duration of stay • Purpose of stay • Citizenship • Place of birth • Alone or in combinations … • in which order? • for which purpose?  Used differently by different sources and depending on objective

6. Definition of Int’l Mig (FLOW) • An international migrant is a person who changes his/her own country of usual residence (UN RSIM, Rev. 1) • Place of usual residence? • “… normally spends daily period of rest” • Usual ≠ legal • Boarding students? “Weekly commuters”? • No provision for … • Duration of stay • Purpose of move

7. Long- vs. Short-term migrants (UN RSIM Rev 1.) • A long-term migrantis a person who moves to a country other than that of his/her usual residence for a period of at least a year (12 months) • A short-term migrant is a person who moves to a country other than that of his/her usual residence for a period of at least 3 months but less than a year (12 months)(except for recreation, holiday, business, medical treatment, …)

8. Definition of Int’l mig.(STOCK) • “Persons who have ever changed their country of usual residence i.e. spent at least 1 year in a country other than the one in which they live at the time data gathered” (UN RSIM Rev. 1) • Relevant population groups: • foreigners (non-citizens of country of usual residence) • foreign-born (born in country other than one in which they are being enumerated) • provisions for 14 special groups

9. Alternative definition (Bilsborrow et al, 1997) “An international migrant is a person who have lived for at least 6 months in a country other than that in which they are being interviewed and whose move into the country of interview occurred during the 5 years preceding the interview” … but definition assumes presence!

10. Complementary definition (Bilsborrow et al., 1997) “An international migrant is a person who used to live in the country in which the interview is being conducted and was a member of the household of the person being interviewed but who left at some point in time during the 5 years preceding the interview to live abroad for at least 6 months”

11. Operationalizing definitions • Usual Place of residence • Some countries do not use concept of “migrant” • Why 3-6-12 months? • Intended vs. actual duration of stay? • at time of arrival based on intention • upon completion of 12-month period • Lots of provisions!

12. Data sources • Population registers • Other administrative records • Population censuses • Surveys

13. Data sources: Pop Registers • PROS • Continuous • Measure of FLOWS (consistent with STOCKS) • De facto duration of stay/absence (if centralized) • CONS • Not run by NSO; coordination • Only limited information • Often not public access • Often only nationals; only documented • (dis)Incentive to register/deregister • Intended vs. actual duration of stay • Quality variability (if decentralized) • Feasible for LDCs? (EU from PopCensus to Registers) • Only 15 countries reporting flows figures (mostly from pop registers; UK, NZ from border statistics)

14. Data sources: Other admin records • Border crossings (flows) • Registry of foreign workers • Embassy/consular data • Resident permit holders/applicants • Diaspora organizations/NGOs in D country • Emigration clearance certificates • Destination country sources … often incomplete both in coverage and content

15. Data sources: PopCensus • Most reliable source of internationally comparable IMMIGRANT stocks. • PROS • Universal coverage • Some characterization possible, based on basic demographics and socio-economic, e.g.: • Gender (feminization of migration) • Age (SSS; fertility) • Occupation (workforce) • Educational level (brain drain/gain)

16. Data sources: PopCensus (cont’d) • CONS • Every 10 years • Limited information (policy analysis?) • Poor/delayed tabulation • Low training of enumerators/data quality • Different approaches/definition • De facto (present population) vs. de jure (usual population) • 14 sub-groups for special treatment • Under-coverage • Entire families that moved • Seasonal/temporary, circular (night prior to census date) • Marginal groups (undocumented migrants?) • Housing arrangements, language, distrust, mobility, …

17. Data sources: PopCensus (cont’d) (Chen, 2006)

18. Data sources: PopCensus (cont’d) • Only 1 country in 89 compliant with UN RSIM Rev.1 (of 153; of 196)! • 11 countries “close” to definition • citizenship (93 countries) • stateless • place of birth (112 countries) • new countries • PoR at some point in time in the past (88 countries) (Chen, 2006)

19. Data sources: PopCensus – emigrants? • Self-reporting about “absentees”: based on socio-econ status (hh membership) • Two (indirect) methods based on demographics (IUSSP) • Place of Residence (PoR) of siblings • PoR of children (complementing existing sources; split surviving children by PoR) • Even more limited information on emigrants • Less “flexibility” • No sensitive info (affect coverage) • Feasible at all? • Quality of information • Proxy respondent • Enumerator’s training • Balance equation/residual (Albania) • Using data from PopCensus in D countries?

20. Data sources: Surveys • Despite “hype”, haphazard efforts • Little attention in … • UN RSIM Rev 1. • EGM recommendations: “Countries should explore the possibility of using sample surveys to collect data on international migration, especially for those aspects for which no other sources are available” • PROS • In-depth analysis • determinants, distributional analysis, impact (??) • More flexibility • Emigration (last resort?) • CONS • Rare event, clustered • Sampling error • Sampling frame (emigrants) • Richer info but … still limitations through proxy respondents

21. Survey options: prob vs. non-prob • Probability: finding rare events • Huge sample? • 8 procedures (Kish, 1965) • Disproportionate • Two-phase • Non-probability • Case studies • Purposive geo selection (NIDI/Eurostat) • Snowball • Aggregation point intercept (Brazil-Nikkei)

22. Survey options: HH vs. non-HH • Passenger surveys • UK IPS (flows) • Low incidence • Short questionnaire • HH surveys • Specialized • Preferred option but … • Too costly/unfeasible • Limited thematic coverage • Piggy-backing • Richer info (welfare?) but shorter migration module • Marginal costs • Sampling issues • LSMS/IHS (small sample; Albania), HBS/IES (high non-response; “resistance”); LFS (larger sample; frequency; no welfare; Philippines)

23. Survey on Overseas Filipinos (SOF) • Long tradition; now integral part of LFS. • 1982: 1-page rider to ISH • 1987: part of LFS (OFW only) • 1993: expanded module, renamed (OF) • 2003: Master sample (51,000 HHs) • Estimates and characterize stock of overseas Filipinos, including OFW (presently AND temporarily working overseas in last 5 year period) [1.2M in 2004]

24. Questionnaire Contents / Design

25. Identifying a migrant in HH • Approach 1: “Typical” LSMS/IHS • Self-reported hh membership (“usually” eat and live together) • No. months absent in past 12 months • Provisions, for HH head, new-comers … • Several drawback: • Permanent migrants? • Exclusion based on arbitrary cut-off • Ambiguous • Misses entire HHs

26. Identifying a migrant in HH (cont’d) • Approach 2: “in the last 5 years, did anyone who livesor lived with you go to live in another country?” • Captures recent migrants but … • Still ambiguous • Arbitrary reference period • Still misses entire HHs

27. Identifying a migrant in HH (cont’d) • Approach 3: Extended roster (with flap) • List all present and former hh members irrespective of PoR • Captures all members but … • Still ambiguous • Incentive to underreport? • Misses entire HHs

28. Identifying a migrant in HH (cont’d) • Approach 4: Expanded fertility module (Albania LSMS 2002) • From 15-49 to “above 15” • List all women in age group • List all children ever born from woman • PoR for still alive • However … • Still possible undercount • mother absent • Misses entire HHs

29. Once identify (e)migrant … • How much information can you elicit through proxy respondent? What’s the min-MAX amount of info? • Age, gender, occupation (before and during) • Length stay abroad/year of departure • Country of destination • Living with spouse/children • Legal status? • Multiple episodes? • Recall methods • Less accurate through proxy • Recall bias (Smith and Thomas, 2003; Som, 1973)

30. Albania LSMS 2005 • Expanded module on (permanent) migrants (non-hh members) plus contact information for tracking in D country • Full histories and characterization of migration of current household members (15 years) • “Bound” grid • Clear time-marks

31. Migration histories of HH members

32. What if entire HH moves? • If dwelling occupied • Ask new occupant • About location • About relatives still in communities • If dwelling vacant/destroyed • Ask neighbor • Ask neighbor about relative still in community • If “dwelling moved”? • Internal migrants • “Restricted” universe of analysis • Track them? Feasible?

33. Tracking migrants • “Replace” proxy respondent • Issues • Info needs • Attrition • Costs • Albania (“forward” tracking) • Tonga (“backward” tracking)

34. Tracking Albanian migrants in Greece • Contact info • Process • Greece only; list of migrants with contacts • 1st contact in Greece • Return visit in Fall (phone cards) • 2nd contact in Greece • Interview • High attrition • No contact info • Unable to locate • Islands (high costs) • Refusal (not high) • Returnees/high mobility • Selection bias(es)? (undocumented aliens)

35. Conclusions • Standards not uniformly adopted across and within countries (depending on source), and changing • Definition to be adopted depends on objective at hand and sub-populations of interest • Census: stock, but … • Registers: flows, but … • Survey: Surprisingly, still little attention … • “Weakest link”: emigration! • Better estimations • Better characterization • Better sampling frames

36. Next steps: WB’s role? • 2010 Round of PopCensus • Influence Qx design • Min set of questions on immigrant stock • Question on Emigrant? • Approximation for stratification in sampling frame • Improve admin records • TFSCB • Register (if available) and/or border crossing • Inter-institutional collaboration • Data access

37. Next steps: WB’s role? (cont’d) • HH surveys • Support proper sample designs • Sampling frames of emigrants • “enhanced” PSU listing for 2-stage • Oversampling in planned surveys • Reduce undercount/misreporting • Fielding and validation of ≠ approaches (LSMSIV) • Adjust for entire migrant households • Specialized vs. multi-purpose • Better income-based measures

38. Next steps: WB’s role?(cont’d) • HH surveys (cont’d) • Improve content • Much more flexibility allowed • Emigrants, Returnees, … • If migrant present • Histories of migration • Retrospective data, determinants • Through proxy • Minimal set of questions? • Contact info for tracking (sub-sample?) • Tracking surveys • Panel surveys • Make provision in baseline