Mapping UK population over timepopulation over time

Open Data Workshop, Nottingham, 21 June 2011

David Martin, University of Southampton

Presentation overview

• Small area spatial population distributions

• The time dimension

• Exploiting Open Data

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• Modelling and mapping population 24/7

Acknowledgements: Samantha Cockings, Samuel Leung, ESRC Award RES-062-23-1811

Small area spatial population distributions

• Resource allocation: large areas > small areas

• Targeting services/marketing

• Site location decisions/transportation demand• Site location decisions/transportation demand

• Denominator populations

• BUT limitations derived by traditional representational concepts and data sources: irregular geographical areas and the missing time dimension

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• Conventional population map interpreted over time

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6Photos: David Martin, Sam Cockings

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• Integrated multi-source datasets interpreted over time

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8Photos: David Martin

Photos:

David Martin

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Space-time population modelling

• Where tried, the general approach is to start with night-time population model/map and transfer population subgroups to specific daytime locations, e.g. schools, workplaces

• Various recent application examples, particularly driven by emergency planning and modelling of population exposure to hazards

• In reality, many different timescales to be modelled, not just simple ‘daytime’ and ‘night-time’

• Longstanding difficulty of obtaining data with sufficient space/time resolution for the non-residential addresses

Modelling frameworkframework

Centroids, boundaries and grids

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Centroid locations and boundaries Centroid populations redistributed onto grid

Origin centroid within area of influence j

centroid i

background layer b

time

study area a

area of influence j

local extent d

t

Data considerationsconsiderations

Total Total populationpopulation

+/+/-- external external visitorsvisitors

Non-residential

Residential

Transport

Total Total populationpopulation

+/+/-- external external visitorsvisitors

Private dwellings

Non-residential

Communal ests.

Employment

Education

Residential

Temp accomm.

Family/social

Retail

Leisure

Healthcare

LocationsLocations

Transport

Generalised local

Tourism

Rail

Metro/subway

Air

Water

Road

Total Total populationpopulation

+/+/-- external external visitorsvisitors

Private dwellings

Non-residential

Communal ests.

Employment

Education

Residential

Temp accomm.

Family/social

Retail

Leisure

Healthcare

LocationsLocations Data SourcesData Sources

- Census, Mid-Year Population Estimates (MYEs)

- Census, Mid-Year Population Estimates (MYEs)

Acronyms: QLFS Quarterly Labour Force; DCSF Department for Children, Schools and Families; HESA Higher Education Statistics Agency; Survey;

DCMS Department for Culture, Media and Sport; ALVA Association for Leading Visitor Attractions; DfT Department for Transport; TfL Transport for

London; CAA Civil Aviation Authority

Transport

Generalised local

Tourism

Rail

Metro/subway

Air

Water

Road

Total Total populationpopulation

+/+/-- external external visitorsvisitors

Private dwellings

Non-residential

Communal ests.

Employment

Education

Residential

Temp accomm.

Family/social

Retail

Leisure

Healthcare

LocationsLocations Data SourcesData Sources

- Census, Mid-Year Population Estimates (MYEs)

- Census, Mid-Year Population Estimates (MYEs)

- Census, Annual Business Inquiry, QLFS

- School pupil numbers, locations, HE statistics

- Prison pops, VisitBritain, Annual Business Inquiry

- VisitBritain

- Annual Business Inquiry, commercial sources

- ALVA Visitor Statistics, DCMS

- Hospital Episode Statistics

Acronyms: QLFS Quarterly Labour Force; DCSF Department for Children, Schools and Families; HESA Higher Education Statistics Agency; Survey;

DCMS Department for Culture, Media and Sport; ALVA Association for Leading Visitor Attractions; DfT Department for Transport; TfL Transport for

London; CAA Civil Aviation Authority

Transport

Generalised local

Tourism

Rail

Metro/subway

Air

Water

Road

- ALVA Visitor Statistics, DCMS

- ALVA Visitor Statistics, DCMS

-

Total Total populationpopulation

+/+/-- external external visitorsvisitors

Private dwellings

Non-residential

Communal ests.

Employment

Education

Residential

Temp accomm.

Family/social

Retail

Leisure

Healthcare

LocationsLocations Data SourcesData Sources

- Census, Mid-Year Population Estimates (MYEs)

- Census, Mid-Year Population Estimates (MYEs)

- Census, Annual Business Inquiry, QLFS

- School pupil numbers, locations, HE statistics

- Prison pops, VisitBritain, Annual Business Inquiry

- VisitBritain

- Annual Business Inquiry, commercial sources

- ALVA Visitor Statistics, DCMS

- Hospital Episode Statistics

Acronyms: QLFS Quarterly Labour Force; DCSF Department for Children, Schools and Families; HESA Higher Education Statistics Agency; Survey;

DCMS Department for Culture, Media and Sport; ALVA Association for Leading Visitor Attractions; DfT Department for Transport; TfL Transport for

London; CAA Civil Aviation Authority

Transport

Generalised local

Tourism

Rail

Metro/subway

Air

Water

Road

- ALVA Visitor Statistics, DCMS

- ALVA Visitor Statistics, DCMS

- National Rail station usage data

- DfT Light Rail Statistics, TfL Tube customer metrics

- CAA UK Airport Statistics

- DfT Sea Passenger Statistics, London River Services

- Traffic count by road/area/vehicle, road map

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Input data points

• Space-time centroid: hidden text

– Population capacity

– Spatial extent

• e.g. primary school, output area centroid

– Pupil numbers

– Small (one cell)– Spatial extent

– Time profile

– Area of influence

– Small (one cell)

– Term dates, school day

– Catchment area (modelled time/space)

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Time profiles

• Variety of sources, but only need reasonable reference time profiles for each type of activity – more detail can be added for specific sites or further subdivision of activity later

• Opening hours by various services readily obtainable • Opening hours by various services readily obtainable (schools, etc.) – Open but not linked!

• Quarterly Labour Force Survey for workforce time profiles (daytime, evening, night working, hours worked, days worked by SIC categories) - not Open or linked!

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Centroid set

• 1696 census OAs

• 3329 workplaces

• 211 schools • 211 schools and colleges

• 2 universities

• Hospitals, stations, airport, etc.

Transport

• Rasterised road background layer Meridian™ 2 v1.1 Release 2 2010

– Motorway (blue)

– Trunk A-Road (green)

– Principal A-– Principal A-Road (grey)

• DfT NTM Area Type in the study area:

– Rural (green)

– Urban (peach)

• AADF Count Points (2006)

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Data considerations (DM ★ ratings??)

• Some sources are explicitly Open (e.g. OS OpenData)

• Some sources are ‘National Statistics’: very clear definitions, standards and documentation (e.g. census); not formally Open, maybe Linked dataformally Open, maybe Linked data

• Some sources are thoroughly documented: at least we understand the limitations, reference dates, completeness (e.g. DfT), limitations, temporal consistency (e.g. HES)

• Some sources are as yet not Open or Linked (e.g. ABI) or are not government sources (e.g. ALVA): varying metadata and reliability

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Sample outputs

16:00

Workplaces, FE & HE institutions still open, schools

Southampton, 200m cells

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schools closed; low residential; very high central densities

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Conclusion

• Longstanding limitation of population mapping has been focus on static residential locations

• Availability of meaningful data describing the time-geography of population has been enduring obstaclegeography of population has been enduring obstacle

• Contemporary applications demand more realistic approach to space-time dynamics

• Real progress is possible in the light of increasingly Open data: might it ever be real-time?

• Data availability is rapidly facilitating new conceptual and methodological developments: still much further to go!

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Acknowledgements

• ESRC Award RES-062-23-1811; Employee data from the Annual Business Inquiry Service, National Online Manpower Information Service, licence NTC/ABI07-P3020. Office for National Statistics 2001 Census: Standard Area Statistics (England and Wales): ESRC Census Programme, Census Dissemination Unit, Mimas (University of Manchester). National Statistics Postcode Directory Data: Office for National Statistics, Postcode Directories: ESRC Census Programme, Census Geography Data Unit (UKBORDERS),

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ESRC Census Programme, Census Geography Data Unit (UKBORDERS), EDINA (University of Edinburgh). Quarterly Labour Force Survey, Economic and Social Data Service, usage number 40023. Meridian™ 2 v1.1 Release 2 2010, Contains Ordnance Survey data © Crown copyright and database right 2010