Intro & Ch 1 Flashcards
What does GIS stand for?
Geographic Information System or Science
What is A system of hardware and software that links mapped objects to attribute information that describes them and provides tools to store retrieve and manipulate both types of data?
GIS
What is GIS?
A system of hardware and software that links mapped objects to attribute information that describes them and provides tools to store retrieve and manipulate both types of data.
Give 3 examples of areas of study that benefit from GIS
City and Regional Planning
Hydrologic Modeling
Security
Geotechnical Engineering
Transportation
Marketing
Real Estate
Business
Politics
Environmental Studies
Name 3 General GIS tasks
- visualize database information
- combine data from various sources
- understand special relationships
What can a GIS do?
Fill in on computer
What are the 4 system components of GIS?
People/staff, data, hardware, software
discrete vs continuous data
discrete objects: objects exist in a defined location
continuous: data exist everywhere
What is the kind of data that exists in a defined location?
discrete
What is the name for data that exists anywhere?
Continuous
Canoe shelter locations is an example of what kind of data?
Discrete
An elevation raster is an example of what kind of data?
continuous
Is the raster data model grid-based or object-based?
grid-based
Is vector data models grid-based or object-based?
object-based
Are raster continuous or discrete data?
Continuous
Are vectors continuous or discrete data?
discrete
What are stored map objects?
features
What is a collection of similar features stored together, like states or rivers?
feature class
what are the 3 features?
points, lines, polygons
In the ____ model, Spatial features linked to table by unique identifier (FID or OID)
vector
In the vector model, what is the relationship between feature and row in table?
1:1 relationship
In the ____ model, Geographic space is quantized into uniformly-sized discrete units, called pixels or cells
raster model
Name at least two strengths of the vector model:
Can store individual features such as roads or streams with a high degree of precision
Linked attribute table provides capability to store and manipulate feature attributes
Suitable for mapmaking due to great feature detail
Ideal for network modeling
What is a weakness of the vector model?
Poorly suited to map continuous data
Some analysis can be time consuming (updating county level parcel data)
_______ is the ratio of distance on the map to distance on the ground
map scale
What is map scale’s dimension?
it is dimensionless
A ____ scale map covers a larger geographic region such as the world
small
a ___ scale map covers a relatively small geographic area
large
Does a small-scale map cover a large or small geographic area?
large
Does a large-scale map cover a large or small geographic area?
small
____ data source is tracked backed to land surveyor’s professional stamp
authoritative
What is a measure of the size at which features in a map are
represented?
Map scale
A ___ scale map is one in which the ratio is large
large. Thus, a 1:24,000 scale map has a larger scale
than a 1:100,000 scale map. A large-scale map shows a relatively small
area, such as a city, whereas small-scale maps show bigger areas, such
as states or countries.
What is simplifying the
data for digital storage (ex. river as a line at a small scale)
generalization
______ describes how closely the x-y values of a data
set correspond to the actual locations on the earth’s surface.
Geometric accuracy
What type of accuracy determines if something is where it says it is?
geometric accuracy
______ refers to how accurate the attributes stored in the table are to real life
Thematic accuracy
What are some things that could cause a lack of thematic accuracy?
How is it measured?
How accurate are the measurements?
What are the possible sources of error?
Mistypes, things that cannot be known exactly (ie census)
___ evaluates whether a data model or data set accurately represents the real-world relationships between features.
logical consistency
____ stores information about the
data set, such as where it came from, how it was developed, who
assembled it, how precise it is, and whether it can be given to another
person.
metadata
What are web maps?
Maps that only uses GIS services (available online)
____ provide geospatial data over Internet connections.
GIS servers/services
What is information about map features stored in columns of a
table?
attributes
What are attributes?
information about map features stored in columns of a table
What is a a square data element in a raster corresponding to one value
representing conditions on the ground?
cell
What is a cell in the raster model?
a square data element in a raster corresponding to one value
representing conditions on the ground
What kind of data takes on a variety of values and that change
rapidly across a data set, such as elevation?
continuous data
What is a data construct designed to store information as tables?
database
What is a database?
a data construct designed to store information as tables
described data that represent distinct spatial objects such as
wells, roads, or counties is ____
discrete data
___ is a spatial object composed of one or more x-y coordinate pairs
and having one or more attributes in a single record of an associated
table.
Feature
___ is a a set of similar objects with the same attributes stored together in a spatial data file
feature class
What is the accuracy with which the shape and position
of features are represented?
geometric accuracy
____ is the analysis of spatial data layers, such as dissolving, intersecting, and merging
geoprocessing
What is a spatial data layer that is tied to a specific location on the earth’s surface for display with other data?
georeferenced data
____ is information stored about data to document their source,
history, management, uses, and more
metadata
What is a a data set composed of an array of numeric values, each of
which represents a condition in a square element of ground?
Raster
____ is the degree to which attribute values represent the true properties in the real world
thematic accuracy
What is a spatial data storage method in which features are represented
by one or more pairs of x-y coordinate values forming points, lines,
or polygons
vector
T or F
The vector model is best for continuous data. The raster model is best for discrete data.
F
T or F
The raster model stores features as map objects called points, lines and polygons
F
The vector model stores features as map objects called points, lines and polygons. The raster model breaks the map area into small cells knowns as pixels, grids, cells or rasters.
Thematic accuracy is not related to data location
T
Thematic accuracy is related to the accuracy of the attributes. Geometric accuracy is related to a feature’s location
T or F
Logical consistency assesses how well data represents real-world relationships
T
For example, do roads connect at intersections? Do county and state boundaries align?
When GIS servers provide data over the internet (streaming data), this is an example of a
map service
Match the data type with the map type
Nominal
Numeric (Interval and Ratio)
Categorical
Single Symbol
Graduated Symbol and Graduated Color
Unique Values
Nominal-single symbol
Categorical-unique values
numeric-graduated symbol
T or F
Data or Numeric Classification applies only to vector data
F
Correct. Data or Numeric Classification applies to vector and raster data. Numeric raster data can be classified (elevation ranges)
Quantile classification puts the same number of features into each class
T
MAUP stands for
Modifiable Areal Unit Problem
In an attribute table, dividing each value by the total of all the values is another way to _____________ data
normalize
