What is GIS?
A computer-based system for handling geospatial data
It turns location-based facts into geographic information, and ultimately into knowledge for decision-making.
List the six components of a GIS.
- People
- Data
- Hardware
- Software
- Procedures
- Network
Each component plays a crucial role in the functionality of a GIS.
What does GISc stand for?
Geographic Information Science
It uses the scientific method to create knowledge about the Earth.
Why is location crucial in GIS?
It allows analysis of patterns, relationships, and trends across space
Applications include traffic routing, disaster management, business planning, and environmental science.
What is Tobler’s First Law?
“Everything is related to everything else, but near things are more related than distant things.”
This principle is foundational for spatial analysis.
Define Spatial Autocorrelation.
The concept that values closer in space are more likely to be similar (positive) or dissimilar (negative)
It helps in understanding spatial patterns.
What is Distance Decay?
The weakening of a pattern or interaction with increasing distance
It reflects how spatial relationships diminish over distance.
What are the four measurement scales of attribute data?
- Nominal
- Ordinal
- Interval
- Ratio
Each scale has different properties and uses in data analysis.
What is sampling in geographic data collection?
Strategies used to collect representative data
Examples include random and stratified sampling, with awareness of potential biases.
What are the two world views in representing geography?
- Discrete Objects
- Continuous Fields
These views influence how data is modeled in GIS.
What does the Vector Data Model use to represent objects?
- Points
- Polylines
- Polygons
It is excellent for precise locations and attributes.
What does the Raster Data Model use to represent space?
A grid of cells (pixels)
It is ideal for continuous surfaces and imagery.
What is generalization in GIS?
Simplifying features when changing scale
Methods include simplification, displacement, and amalgamation.
What is Primary Data Capture?
Collecting new data directly
Examples include GNSS/GPS, Remote Sensing, and Field Surveying.
What is Secondary Data Capture?
Using existing data
Examples include digitizing maps and using Photogrammetry.
What is Volunteered Geographic Information (VGI)?
Data contributed by the public
Examples include OpenStreetMap, but it requires careful consideration of quality and biases.
What does Analysis by Location answer?
“Where” questions
It is a fundamental aspect of spatial analysis.
What are Overlay Operations in GIS?
- Union
- Intersect
- Clip
These operations combine layers to analyze spatial relationships.
What is Buffering in spatial analysis?
Creating zones of a specific distance around features
It helps in understanding proximity and influence areas.
What is Spatial Interpolation?
Estimating unknown values between known points
Methods include IDW and Kriging.
What does MAUP stand for?
Modifiable Areal Unit Problem
It highlights how results can change based on boundary definitions and analysis scale.
What is the purpose of Remote Sensing?
Obtaining information about the Earth’s surface without physical contact
It involves detecting and measuring reflected or emitted energy.
What are the two types of Remote Sensing sensors?
- Passive sensors
- Active sensors
Passive sensors use sunlight, while active sensors provide their own energy source.
What is a Spectral Signature?
Unique ways different materials reflect light
It allows identification of materials like water, vegetation, and soil.
