A zone design approach for investigating inequalities in infant mortality Konstantinos Daras (University of East Anglia) Seraphim Alvanides (University of Newcastle) Ian Gregory (Queen's University Belfast) 3 rd International Population Geographies Conference June 2006, Liverpool, UK

2 The Geography of Infant Mortality in England & Wales ( )  Was there a north-south divide?  Looking at inequalities:  Between urban/rural LGDs  Between/within counties  Between/within automated zones

3 Infant Mortality Rate (IMR)  Infant mortality: Deaths before 1st birthday per 1,000 live births Social class Urban/rural Low income Overcrowded Unhygienic  Infant mortality is related to:

4 Infant Mortality Rates in England and Wales ( ) World War I World War II (Source: Beaver (1973): p. 244)

5 Decline of Infant Mortality Conventional explanations:  Cities had high rates because of rapid urban growth  Lower rates were driven by improvements in sanitary conditions in towns and by better health care.  Improvements started simultaneously across the whole country in the 1880s. After Woods et al (1988 & ’89); Lee (1991); Williams and Galley (1995); Woods (1997)

6 Data sources (1)  The Great Britain Historical GIS (Gregory and Southall, 1998)  1911: 2061 Local Gov. Districts  1928: 2037 Local Gov. Districts  1951: 1527 Local Gov. Districts  1971: 1419 Local Gov. Districts (Data aggregated to 1971 level)  Infant deaths (before 1st birthday)  Infant births  Estimated population  Urban/rural classification

7 Data sources (2) World War I World War II (Source: Beaver (1973): p. 244)

8 Measuring Inequalities  Gini coefficient  Coefficient of variation  Variance of logarithms  Theil’s entropy index Between areas inequalities: Gini coefficient of areas Within areas inequalities: G a : Gini coefficient of area a N : number of areas

9 Zone Design  Aggregation of areal units into zones, so that certain criteria are satisfied.  Available zone design systems  AZP (no GIS): Openshaw (1977, 1984)  ZDES: Alvanides et al. (1999, 2000)  AZM: Martin (2002)  A2Z: Daras (2005), O-O & Graph theory

10 How A2Z works Optimises an objective function Optimises an objective function Controls the contiguity of zone Controls the contiguity of zone

11 A2Z components Initial Aggregation ( Random or user ) Shape Constraints (Weak or Strong compactness ) Boundary Constraints ( Railway, A road, Wards ) Objective Function ( Homogeneity )

12 Zone design settings  62 output zones  Random initial aggregation  Weak shape constraint Target IM patternsTarget Urban/Rural zones

Infant Mortality Rates (LGD level) LGDs (1928) LGDs (1951)LGDs (1971) LGDs (1911)

14 Between LGDs inequalities

Infant Mortality Rates (County level)

Infant Mortality Rates (output zones based on the similarity of IMR)

Infant Mortality Rates (output zones based on the similarity of population)

18 Between areas inequality

19 Within areas inequality

20 Summary (1)  There has been a steady decline in infant mortality since the 1900s  This masks some complex geographical variations:  Between urban area inequalities remained fairly constant in 1928 and 1951  Between rural area inequalities increased throughout the study period  The automated zones suggest a decline of inequalities in 1951, while the counties record such reduction in 1971  Possible explanation: at period urban inequalities remain steady because of better health care.

21 Summary (2)  Traditional descriptions and explanations of these are limited and over-simplified  This method allows comprehensive description but does not provide explanation  Zone design can provide a useful tool for highlighting problems.

22 Further research  North/South divide:   Automated zones (2 zones)  Further investigation of 1928 – 1951 period  Different aggregation levels (scale)  Extend the analysis of IM inequalities on annually data  Any available socio-economic data (possible explanations).

A zone design approach for investigating inequalities in infant mortality Konstantinos Daras Seraphim Alvanides Ian Gregory 3 rd International Population Geographies Conference June 2006, Liverpool, UK