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Social science that makes a difference

Social science that makes a difference

Geospatial technologies to the rescue: enhanced socio-economic research

Gina Weir-Smith and Tholang Mokhele

26 October 2016 HSRC Seminar, Pretoria

Social science that makes a difference

Outline of presentation

• Purpose of presentation
• Background
• Visualisation
• Sampling
• Fieldwork mapping
• Spatial analysis
• Conclusion

Social science that makes a difference

Background

• GIS - a decision support system involving the integration
• f spatially referenced data in a problem-solving

environment

• An information technology which stores, displays and

analyses both spatial and non-spatial data

• True value of GIS lies in its ability to analyse spatial data

using the techniques of spatial analysis

• These are
• Data visualization
• Exploratory data analysis
• Modelling

Social science that makes a difference

Background cont.

• Common applications
• territorial control e.g. boundary survey data
• natural resource exploitation e.g. vegetation and soil
• socio-economic profiles e.g. population, housing,

health, education, etc.

• Monitoring
• event monitoring e.g. crime, fire statistics, etc.
• monitoring of environment e.g. wild life, air, soil and

water data

• Management and planning
• natural resource management
• infrastructural planning and service provision

Social science that makes a difference

Visualisation

• People remember
• 10% of what they hear
• 20% of what they read
• 80% of what they see and do
• Visual tools (imagery, maps and graphic products) are

important to understand the complexities of spatial information

• GIS integrates data from different sources
• statistical databases
• paper maps
• surveys
• remote sensing

Social science that makes a difference

Visualisation cont.

• Two types of maps
• Topographic maps portray the

earth’s surface as accurately as possible subject to the limitations of the map scale e.g. houses, roads, vegetation, relief, geographical names, and a reference grid

• Thematic maps represent the

distribution of a particular phenomenon e.g. crime hotspots, population density

Social science that makes a difference

Visualisation cont.

• How do I say what to whom?
• ‘What’ = spatial data and its characteristics
• ‘Whom’ = the map audience and purpose of the map
• ‘How’ = design rules themselves

Social science that makes a difference

Sampling

Methods

• Random sampling (Probability)
• Simple
• Stratified
• Multi-stage
• Non-random sampling (Purposive)
• Systematic
• Convenience
• Snow ball

Social science that makes a difference

Sampling cont.

• Stage 1 - Province
• Geo type, i.e. Formal, Informal, Urban, Rural, Farms
• Stage 2 - Primary Sampling Units from Master Sample of

1000 EAs or Small Area Layer (SAL)

• Sample unit-based sampling: points or polygons are

selected from a sample frame

• Stage 3 – Secondary Sampling Units – Dwelling Units/

Visiting Points/ Households from sampled EAs or SALs

• Area-based sampling: Random points are generated

within a polygon

Social science that makes a difference

Sampling cont.

• Dwelling unit frame data
• Coordinates
• Random selection
• Imagery (raster)
• GIS (vector)
• Statistical software
• Stata or SPSS

Social science that makes a difference

Fieldwork mapping

• Value of fieldwork mapping
• Guide the Principal Investigators (PI) or

planners with logistics

• Assist and co-ordinate planning fieldwork

trips

• Assist fieldworkers with directions
• Identify houses that need to be surveyed

Social science that makes a difference

Fieldwork mapping cont.

Social science that makes a difference

Fieldwork mapping cont.

• Types and scale of fieldwork maps
• National
• Provincial
• SAL/ EA Maps (these are detailed maps)
• Overview maps
• Street maps
• Household maps or Visiting Points (VP) maps

Social science that makes a difference

Fieldwork mapping cont.

Fieldwork mapping cont.

Spatial analysis

• Hot spot analysis
• Identifies statistically significant hot spots and cold

spots - Getis-Ord Gi* statistic

• Warm values = similar and high
• Cold values = dissimilar and low
• Z score around zero = no apparent spatial clustering
• Spatial concentration
• Test spatial randomness of trends
• Useful to identify spatial concentrations

Social science that makes a difference

Social science that makes a difference

Spatial analysis cont.

• 3D mapping
• Visualize socio-economic phenomena
• Highly graphical representation of spatial patterns,

e.g. areas with high rate of poverty

Social science that makes a difference

Social science that makes a difference

Spatial analysis cont.

• Spatial autocorrelation (Moran’s I)
• Considers feature location and attribute values
• Is the pattern expressed clustered, dispersed or

random?

• Positive Moran's I index - tendency toward clustering
• P-value refers to probability
• Small value means very unlikely (small probability)

that the observed spatial pattern is the result of random processes

• Z-scores are standard deviations

Social science that makes a difference

Social science that makes a difference

Social science that makes a difference

Spatial analysis cont.

• Remote Sensing (RS)
• The science of acquiring information about the earth’s

surface from a distance, typically from aircrafts or satellites

• Done by sensing and recording reflected or emitted

energy and processing, analyzing and applying that information

• Spatial and temporal dimensions
• Spatial resolution
• Temporal resolution
• Linkages - GIS and RS

Social science that makes a difference

Social science that makes a difference

Spatial analysis cont.

Social science that makes a difference

Conclusion

• Relevance of geospatial technologies
• GIS Centre provides spatial solutions to evidence

based research

• Power of location based solutions
• Improved efficiency - undertaking empirical surveys
• Sampling and mapping
• Earth Observation
• Robustness in data analysis
• Spatial and inequality analysis
• Integration of multi-disciplinary dimensions
• Human Dynamics, Sustainable Development Goals