S patial homogamy Geographical dimensions of the partner market in the Netherlands

1. Spatial homogamyGeographical dimensions of the partner market in the Netherlands Karen Haandrikman Demography Department Faculty of Spatial Sciences University of Groningen

2. ‘Cupid may have wings, but apparently they are not adapted for long flights’(Bossard 1932) Objective of the PhD project:To explore and understand the role of geographical distance in partner choice in the Netherlands

3. The study consists of three parts: • Description of spatial patterns of spatial homogamy • Explanation of the spatial patterns found • Life course trajectories • Regional cultural differences • Socio-economic status • Meeting places • Understanding the motivation to choose a spatially homogamous or heterogamous partner

4. Conceptual model people tend to choose partners who live nearby geographical distance distance between partners information, time, energy, costs uneven distribution of population social and cultural groups are geographically clustered demographic factors region spatial factors • population density • urban/ rural • location • regional cultural differences • age • sex • household position

5. Research questions • What factors explain spatial homogamy in the Netherlands? • Demographic factors: age and household position • Socio-economic status: education, income, house values • Spatial factors: geography, core/ periphery, urban/ rural • Cultural factors: religion/ denomination, dialect

6. Partner choice determined by distance

7. Partner choice determined by distance and other spatial factors

8. Data Cooperation with Statistics Netherlands GBA, the Dutch Population Register (1995-2004) • Personal Identification Number • Personal Lists • All migration is registered • Linkages between PINs Social Statistical File (1999-2003) • Linked registers in which demographic and socio-economic data are stored • Data from insurance registers/ tax registers etc. • PINS are available • Longitudinal data

9. Operationalisation • Spatial homogamy: distances between partners the distance between the former addresses of cohabiters and their birth places • Cohabiters: persons who • are married (GBA) OR • have a registered partnership (GBA) OR • are cohabiting • derived from household statistics • household positions are mostly (93%) established on the basis of relationships to other persons at the address • if it is not clear what household position a person has, the position is estimated using an imputation model (by Statistics Netherlands)

10. Data and study design GBA, the Dutch population register (N of registrations 01/01/2005=16,305,526) Annual Household Statistics (N of households 01/01/2005=7,090,965) Persons experiencing a transition to living together in 2004 (N=326,538) Address before cohabitation Address 5 years before cohabitation Birthplace partner1 partner2 distance p1 p2 distance p1 p2 distance

11. Measuring distance • ACN-coordinates identify each individual address through the 6-digit postal code and house number • Distances are calculated by computing the Euclidian distance and gives the exact distance between partners before cohabitation, in meters • Distance between birth places are calculated by measuring the distance between the centroids of birth municipalities of partners (taking into account all municipal redivisions from 1900-1980) • No address means no distance

12. Distance decay in partner choice2004, all new cohabitations

14. Research problems (1) GIS issues • Other distance than Euclidian distance? e.g. traveling distance • Use Cost Weighted paths? How to define costs?

15. Research problems (2) Spatial models • Micro data • Which aggregate regional level? • Not available on individual level: education, religion, dialect • Combination of data on individual and regional level • Many explanatory variables have a clear spatial pattern • Spatial autocorrelation: on the basis of what?