Ch 6

Question 1

The dimensions of a pixel is the

Answer 1

resolution

Question 2

What are the benefits of using the raster model

Answer 2

Veterans during certain kinds of data (continuous), better analyzing certain types of data, often faster analysis than vectors, imagery desirable for certain maps

Question 3

What are the drawbacks of the raster data model

Answer 3

Coordinate precision is generally lower than the vector model, high precision has high storage costs, cannot store multiple attributes

Question 4

What are the four types of raster formats that can be analyzed in arc GIS

Answer 4

File geo-database raster (FDGDR), tiff, ER DAS, GRID

Question 5

Give one example of a raster type

Answer 5

Digital elevation model (DEM), color aerial photograph, land-use categories, scanned topo map or digital raster graphic, arc GIS online base map tile, roads

Question 6

The precision of a raster is limited by the

Answer 6

resolution

Question 7

_____ is changing the resolution of a raster, producing a new copy

Answer 7

Resampling

Question 8

_______ groups pixels and determines the new value using a statistic

Answer 8

Block resampling

Question 9

_______ grabs the value from the old cell that falls at the center of the new cell. It preserves the original value and should always be used with categorical data, or when the original data values need to be preserved. It is the fastest method

Answer 9

Nearest neighbor resampling

Question 10

______ calculates a new value from the four cells that fall closest to the center of the new cell. It uses a distance-weighted algorithm based on the old cell centers. It is best used with continuous data such as elevation

Answer 10

Bilinear resampling

Question 11

______ calculates a new value from the sixteen cells that fall closest to the center of the new cell. It uses a distance-weighted algorithm based on the old cell centers. It is best used with continuous data such as elevation. It is the most time-consuming method

Answer 11

Cubic convolution resampling

Question 12

Give an example of a time when resampling is required in the raster data model

Answer 12

When projecting rosters or when analyzing two wrestlers with different resolutions

Question 13

______rasters store values representing measurements or categories and can be analyzed.
______ rasters store color values (like taking a picture of a map) and cannot be analyzed

Answer 13

Data, Picture

Question 14

Give an example of a data raster

Answer 14

Elevation, aerial imagery, land-use, roads

Question 15

Give an example of a picture Raster

Answer 15

Scanned topo map, base map

Question 16

_____is a special value used in some raster formats to indicate absent data

Answer 16

NoData

Question 17

______ creates a real-world coordinate system for an image
that lacks one, usually because it is a map picture or scan. A
_______session starts by adding the data with a real-world
coordinate system, the reference layer, first. Then add the image.

Answer 17

Georeferencing x2