Chapter 12 - Spatial Estimation Flashcards
What are three common spatial estimation methods?
- Spatial interpolation; 2. Spatial prediction; 3. Core area
This estimation method estimates values at unmeasured locals using measured values of the same variable
Spatial interpolation
This spatial estimation method predicts values at unmeasured locals using measured values of other variables
Spatial prediction
This spatial estimation method predicts the chance of occurence of an object or event using probability theory
Core area
What are three different methods of spatial interpolation?
- Creating isoclines; 2. Polygons; 3. Raster
To test spatial interpolation accuracy what is done with some data?
Some data is withheld
What are four sampling methods used in spatial interpolation?
- Systematic; 2. Random; 3. Cluster; 4. Adaptive
This sampling method collects points on a uniform grid
Systematic
This sampling method uses randomly distributed points
Random
This sampling method uses grouped points
Cluster
This sampling method uses more points in variable areas
Adaptive
What are four types of spatial interpolation?
- Nearest neighborhood interpolation; 2. Fixed radius (or local averaging); 3. Inverse distance weighting; 4. Spline
This type of spatial interpolation creates polygons around sample points
Nearest neighborhood interpolation
What is another name for the polygons created in nearest neighborhood interpolation?
Thiessen polygons
This is conceptually the simplest type of spatial interpolation
Nearest neighborhood interpolation
What type of data are poorly represented by nearest neighborhood interpolation?
Continuous data
In nearest neighborhood interpolation, points inside polygons have this
Same value
Is nearest neighborhood interpolation an exact interpolator?
Yes
In this type of spatial interpolation, a circle is placed over each raster cell
Fixed radius (or local averaging)
What is done with sample points within a circle in fixed radius/local averaging spatial interpolation?
Points are averaged and output to cell
What are cells without points assigned in fixed radius/local averaging spatial interpolation?
Zero or null
What happens if a circle radius is too small in fixed radius spatial interpolation?
Many nulls created
What happens if a circle radius is too large in fixed radius spatial interpolation?
Data is smoothed too much
Is fixed radius/local averaging spatial interpolation an exact interpolator?
No