W7

Question 1

What is a zone?

Answer 1

A group of grid cells that share the same value
- can be irregular and disconnected in shape
- can have one or multiple regions

Question 2

What is a zone region?

Answer 2

A group of connected cells in a zone

Question 3

How are zones typically defined?

Answer 3

On a separate grid or feature class

Question 4

What is the value grid?

Answer 4

The grid that is investigated for its values within the zones (so there is a zone layer and a value grid)

Question 5

What are some typical applications of zonal analysis?

Answer 5

Summarize statistics of a value grid for the zones of a zones layer, such as average rainfall per province or maximum tree density per protected area

Question 6

What does the zonal statistics tool do?

Answer 6

A stat is created for each zone (as defined by a zone dataset) based on values from another dataset (value grid). This gives a single output value in the input zone dataset. This can be put into a table.

Question 7

What does the zonal geometry tool do?

Answer 7

returns information about the geometry, or shape, of each zone in a raster.

Question 8

What are the geometry options for zonal functions?

Answer 8

Area, perimeter, thickness, centroid.

Question 9

How can you do cross-tabulation analysis

Answer 9

• Calculates cross-tabulated values between two datasets and outputs a table
• compares to input rasters (these surfaces must be nominal or ordinal)
• all cell locations in output grid are assigned a numerical value that preserves the uniqueness of the combination of classes from input grid

Question 10

What is the region group tool (contiguity)

Answer 10

Spatial analysis operation used to identify connected regions or groups of cells with similar characteristics within a raster dataset.