Strand 2: GIS and Spatial Analysis Flashcards
6 GIS Buzz Terms
Capture, Representation, Management, Manipulation, Analysis, Presentation
Which two models allow GIS to represent the real world?
Raster Model and Vector Model
Characteristics of Vector Model (e.g MapInfo)
- Use in Human Geog + Spatial Science
- Everything is represented as a point/line/polygon
- Geometric Cartesian (x,y) coordinates: POINTS, LINES AND POLYGONS
- Maps world as discrete graphic features
- Links to a data base for ‘attribute’ storage
Characteristics of Points in Vector GIS
- Single x,y coordinate
2. Nodes/Labels e.g buildings
Characteristics of Lines in Vector GIS
- Strings of x,y coordinates
2. Arcs e.g rivers, roads
Characteristics of Polygons in Vector GIS
- Closed string of x,y coordinates
2. Polygons e.g postal areas.
How can GIS be applied?
Decision making and policy making
Classic Example of Spatial Analysis?
1854 John Snow - Cholera
Define Secondary Data
Data already collected for a different purpose but can be accessed and re-analysed
Define GIS
A GIS is a computer system capable of capturing, storing, analyzing, and displaying geographically referenced information; that is, data identified according to location. Practitioners also define a GIS as including the procedures, operating personnel, and spatial data that go into the system.
Examples of key online data sources
- UK Data Service (Census and Boundary data)
- DIGIMAP (Geographic data)
- NOMIS ( Attribute data)
- WICID (Attribute)
Examples of key data issues
- Validity of data ( Metadata)
- Accuracy
- Scale and Generalization
- Projections and coordinate systems
- MAUP and Ecological Fallacy
- Inconsistency in data and geographies
- Confidentiality and disclosure risk
- Purpose
What is Metadata
Metadata is data that describes other data.
What is included in Metadata?
Content Quality Condition Origin Who/Why/When?
Why is Metadata important?
For the integrity of any analysis
