Calibrating census microdata against a gold standard (employment survey): women in the workforce, Mexico 1970, 1990 and 2000 * * * Robert McCaa, Rodolfo Gutierrez and Gabriela Vasquez, Minnesota Population Center Calibrate, v a. trans....to graduate a gauge of any kind with allowance for its irregularities. The Oxford English Dictionary Online (Oxford: Clarendon Press, 2001)

IPUMS i Integrated Public Use Series International Minnesota Population Center University of Minnesota Principal investigators: historians: Steven Ruggles, director MPC Robert McCaa, Matt Sobek demographers: Deborah Levison, Miriam King

IPUMS i goals » 1. Inventory the world’s census microdata a.historical b. contemporary a.historical b. contemporary » 2. Preserve endangered microdata and metadata a. contract preservation with repositories b. archive validated copies * * * » 3. Integrate census microdata and metadata of selected countries on all continents using UN, ECE, and other standards » 4. Disseminate resulting database without charge with full access to all who agree to non-disclosure

IPUMS i integration principles IPUMS i integration principles » 1. Respect absolute anonymity » 2. Preserve all original data, except adjustments to insure confidentiality (top codes blurrings, masking, re-ordering, etc.) » 3. Harmonize (integrate) codes for countries using international standards. occupation: ISCO (detailed, general) education: ISCED “ “ family: IPUMS “ “ » 4. Enhance with constructed variables » 5. Calibrate microdata against “gold standards”

I N T E G R A T E S IPUMSiIPUMSiIPUMSiIPUMSi 12 projects started USA , , Colombia 1964, 1973, 1985, 1993 France 1962, 1968, 1975, 1982, 1990 Mexico1960, 1970, 1990, 2000 Vietnam1989, 1999 Kenya1969 ?, 1979 ?, 1989, 1999 East-West Center (Hawaii) Centro Latinoamericano de Demografia Brazil1960, 1970, 1980, 1991, 2001 Spain1981, 1991, 2001 Hungary1980, 1990, 2001 China ? 1982, 1990, 2000

INTEGRATESINTEGRATES Photos of the IPUMS-Colombia team February-March, 2000: 5 statisticians from DANE +8 academics (3 universities) IPUMSiIPUMSi Standard:UN/Eurostat Principles & Recs... Census documentation compiled for the Colombia project

D I S S E M I N A T E S IPUMSiIPUMSiIPUMSiIPUMSi End-User license agreement protects confidentiality assures proper use User selects countries,censuses,cases,variables, samples--assists comparative research Open architecture software International web-based access system

Calibration test Mexico 1990, 2000: FLFP census microdata vs. employment survey Employment surveys: date from the 80s; many probing questions finely tuned instrument collected by trained interviewers urban--lack national coverage Census microdata: strength: national coverage back to 1960 weakness: untrained interviewers, one question omits many working women, particularly informal workers Purpose of paper: calibrate census microdata w/ employment surveys

Table 1. Selected microdata samples of Mexico, Year Type Sample SizeDensity (%) 1960* Census502, * Census480, CensusNo sample available due to earthquake damage 1990* Census802, , ENEU (survey)172, * Census 10,099, ENEU (survey)562, (*to be integrated in IPUMS i )

The problem (table 2) Mexico’s “global” female labor force participation rate (12-64 years) microdata survey (ENEU): 34.6%43.3% national census: 20.6% 32.9%  A better comparison Control for survey (ENEU) sampling frame: 16 cities in 1990 survey (16 cities): 34.6%41.7% census (16 cities): 29.0% 40.2%*  * includes responses from LFP questions 1 (activity) & 2 (verification).

census--two questions on LFP: 1: “Last week did (NAME)...” 2000 census--two questions on LFP: 1: “Last week did (NAME)...”...” Question 1: Last week (Name): Did you work? 27.5% Had work? 0.4 Look for work? 0.3 Are you a student? housewife? housewife? retired? retired? permanently incapacitated? permanently incapacitated? Did you not work? 2000 census--two questions on LFP: 1: “Last week, did (NAME)...?” 2: “Besides (...), did (NAME)...?” Question 1: Last week (Name): Did you work? 27.5% Had work? 0.4 Looked? 0.3 Q. 1&2: combined student/wrkd 0.5 student/wrkd 0.5 housewife/wr 3.7 housewife/wr 3.7 retired/wrkd 0.0 retired/wrkd 0.0 other/w? 0.4 other/w? 0.4 no reply/w? 0.0 no reply/w? 0.0 Question 2: Did you help in a family business? Sell some product? Make some product to sell? Help on a farm or with livestock? Or in exchange for pay did you do some other activity?

StructureFLFP Rates SurveyCensusSrvyCnss SurveyCensusSrvyCnss Total 62,24863, Education Less than 6 years Completed primary Completed middle Post-middle (10+) Marital Status Married (all forms) Not in union Table 3. Urban Females, 1990 (aged 12-64)

StructureFLFP Rates SurveyCensusSrvyCnss SurveyCensusSrvyCnss Total 124,051 1,073, Education Less than 6 years Completed primary Completed middle Post-middle (10+) Marital Status Married (all forms) Not in union Table X. Females 2000: Urban (same 16 cities as in ENEU 1990) (table not in paper)

Female labor force participation ENEU (indicator) vs. Census Female labor force participation ENEU (indicator) vs. Census Variable B S.E. Wald df Sig R Exp(B) 1990: : Model source effect taking into account age, marital status and education. Table Y. Logistic Regression: Source (Females 1990, 2000; same 16 cities as in ENEU 1990) (table not in paper) Interpretation If for both sources weights are correct and slight structural differences are taken into account: 1990 census under-reported 20% of FLFP census under-reported 20% of FLFP census over-reports FLFP by 9% census over-reports FLFP by 9%.

LFP by sex and marital status Mexico 1990 and 2000 (national figures) Females Males

Marriage and education strongly affect FLFP (Mexico 1990 and 2000, national figures) Married Not

Figure 3. Female labor force participation rates by age United States, and Mexico, 1970, 1990, 2000

Mexican census microdata may be more informative, even about FLFP, than researchers think Mexican census microdata on FLFP display remarkable coherence in time and space “Chorus of calamity” on Mexican FLFP may overlook enormous changes in education weakening power of patriarchy over married women real advances of women in the workforce 2000 microdata tell the story Calibration helps weigh strengths and weaknesses of sources

paper is on conference CD or contact: * * * * * * Thank you