Exam 1 (1-9) Key Terms Flashcards
1
Q
Feature Geometry
A
Points - individual locations
Lines
Areas
2
Q
Landscape Mosaic - Landscape Ecology Patches
A
discrete areas considered to be homogenous in a certain biophysical trait vary in size and shape
3
Q
Landscape Mosaic - Corridors
A
long narrow patches that connect two or more sizable patches
4
Q
Matrix
A
the area that the patches are embedded within represent one condition. The less interested patches are grouped in one based on a shared characteristic and the interesting patches are highlighted
5
Q
Spatial Relationships - Adjacency
A
one entity touching or being near to another
6
Q
Spatial relationships - Contiguity
A
describes condition of multiple features being connected through shared area, edges, or boundaries, sometimes depending on condition
7
Q
Spatial Relationships - Fragmentation
A
describes the degree to which entities present a small disconnected feature, one entity could be fragmented in its shape
8
Q
spatial relationships - Connectivity
A
describes HOW things are connected either directly or through an intermediate
9
Q
spatial relationships - topology
A
describes certain relationships among features without reference to specific shapes, area, or distances
10
Q
spatial relationships - proximity + distance
A
how close one entity is to another
11
Q
Spatial Dibtribution
A
Defined by the spatial relationships among many individual entities
- Dispersed
- Clustered
- Random
- Gradated
12
Q
Spatial correlation
A
Describes the situation where SPECFIC/DIFFERENT types or conditions are found in the same location or close proximity + how frequently this occurs
13
Q
spatial autocorrelation
A
describes the situation where entities of the SAME TYPE or SIMILAR CONDITION are found in same location or close proximity
14
Q
Grid Cell
A
concept of spatial entities that divides space into set order unit (cells) each with same size and shape
15
Q
Bertine retinal Variables
A
color - categorical
shape - categorical
orientation - categorical
value - shading - ordinal data
size - ordinal or Numerical Data
texture - all three
16
Q
Categorical data
A
individual values have no numerical value, ex: forest or agriculture
17
Q
Ordinal data
A
ordered value, example fair, high, low
18
Q
Numerical Data
A
numbered data
19
Q
Reference maps
A
focus on locations of different types of features in the landscape - e.g. towns, major roads, water, topography
20
Q
Thematic maps
A
focus on depicting a single phenomena or set of conditions, show either categorical or statical information
21
Q
Categorical thematic maps
A
typically vary color, shape, texture of features to visually identify its category
22
Q
Statistical Thematic maps
A
usually vary the value of the fill color ( i.e. gradient) or the size of the feature to reflect some numerical value associated with the feature
23
Q
The choropleth map
A
used for statistical data , the relative value of a given feature is represented by its position along a light to dark gradient
24
Q
Normalizing
A
divides the measured value by either the area of the feature (i.e. density) by the highest possible value for that feature (e.g. number of people under 18 divided by the total population)
25
Classifying methods - Equal Interval
ensures that the range of each value in each class is the same
26
Quantile
ensures that there are the same number of features in each class
27
Natural breaks
look for large changes between data values and places class breaks in those locations. Similar values grouped together, breaks where values change drastically
28
Coordinate Systems
indicate location on the Earth's surface as its distance east and north of some arbitary origin point on the surface
29
Spherical Coordinate Systems
identify a location on the curved surface of a sphere (or ellipsoid) - unprojected
set the origin to be the intersection of the equator and prime meridian
The angle measured to the NORTH of the EQUTOR is referred to as the features latitude
The angle measured EAST of the prime meridian is referred to as the features longitude
30
Grid Coordinate Systems
identify location on a flat surface
location of a feature is identified using linear measurements (feet or meters) along surface of the map - projected
origin is any location on the earth surface
Y axis - north
x axis - east
31
Graticule
a grid on a map or globe representing equally spaced (in angular units) lines of lattitude and longitude
32
Shape of the earth
general shape is ellipsoid caused by slight bulging at the equator and flattening at the poles due to earth rotation
Dips and bulges in the Earth's shape result in a complex shape called a GEOID
33
Datums
are mathematically derived estimates of the true shape of the Earth ellipsoid
calculated by creating a best fit curve via a set of CONTROL POINTS which are locations known with a high degree of accuracy
34
Map projections
are algorithmics that mathematically account for distortions that occur in the process of projecting a 3d curved surface to a 2d flat surface
35
Distortions
projections distorts four basic characteristic of spatial entities and their spatial relationships
1. Shape
2. Area
3. Direction
4. Distance
a single projection can only minimize distortion in ONE of these characteristics at a time
36
Developable Surface
the flat surface onto which the curved earth is projected, is a shape that can be flattened without stretching or tearing it. Either tangent or secant to the Earth's surface by bending it into one of three shapes
cylinder, a cone, or an plane
37
Distortion is minimal at
at the line/point where the developable surface is tangent or secant to the earth and increase with distance
38
Projected Coordinate Systems
control where and what types of distortions occur - apply standard projection algorithms but modify the origin of the coordinates - often location of least distortion
39
Map Design Key Considerations
simplicity
context
visual hierarchy
consistency
layout
look and feel
40
Simplicity
achieved by removing visual noise
- examples: heavy outlines and area features, unnecessary pattern and line decorations
features that do no fit maps purpose
41
context
provides the reader with more info than just the data, often the phenomenon we are mapping extends beyond the area of interest
base map + locator map
42
Base Map
provide information about basic landscape structure and administrative boundaries
components
- physical features like water bodies, roads, building, features that can identify specific locations within our area of interest
- elevation data
43
Locator map
helps readers know the location of the area of interest and can be separate or as a part of the main map layout
44
Visual Hierarchy
a structural approach to the design that helps draw the readers eye naturally to find the most important elements of the map
components
- higher contrast from surrounding elements
- more vibrant - saturated colors
- larger features and thicker lines
- Combination of these elements
45
Consistency
treatment of features within conceptual categories that makes map easier to understand
46
Layout Structure
structure in layout and map surrounds
Map surrounds - north arrow, scale bare, legend
consider purpose of each element of map layout and size according to its importance
keep elements aligned
use margins
47
look and feel
should be consistent with the message you want people to take away from the maps content , choose colors, fonts, map surround styles to help reader relate to the maps content
48
GIS (Geographic Information Systems)
Geographic - phenomena at specific location
Information: things events, and conditions have measurable characteristics - including their location
System: these different characteristics can be organized and analyzed according to established structures and procedures
49
GIS textbook definition
a computer based system to aid in the collection, maintenance, storage, analysis, output and distribution of spatial data and information, not a software program
50
GIS 3 components
GIS as a technological construct
GIS as a science
GIS as a process
51
GIS is a technological construct
computer based system
collection, maintenance, storage, analysis, output and distribution of
spatial data and information
52
GIS as a science
Theoretical basis for GIS
the field of research and design that develops the conceptual foundation for GIS as a process and as a technological construct
53
GIS as a process
the field of practice of working with GIS data and software, five components
54
GIS as a process components
software, protocols, people, data, hardware
55
Software
ArcGIS, other types such as QGIS, Carto, idrisi,
we use ArcGIS because it has thousands of tools for storing, managing, editing, and analyzing data, tools for visualizing and presenting data, tools for sharing data and maps, scripting and visual programming
56
Hardware
high powered workstation or laptops
large sever systems
handheld device, data loggers
57
Data
coordinate data - the position on the surface of the earth where a place, thing, or event is located using known coordinate system
attribute data - information about place , thing, event
link between both leads to analysis
58
Protocols
standard procedures for collecting, storing, documenting and distributing data, as well as analysis, design standards
59
People
Growing need for GIS experts - bring order to amount of data, devise and perform complex spatial analyses, develop new software and hardware tools, design effective communicative visualizations for those data and analysis results
growing need for experts in other disciplines with GIS skills,
- determine questions, knowledge of places, things, events, interpret , use it in planning management and design
60
Criticisms of GIS
inherently inaccurate - all data has limitations, not just GIS, can be addressed by considering each datasets intended use
reductive and disconnected from its subject - making GIS analysis a part of diverse approach to examining your phenomenon of interests
Access to GIS is limited - using participatory approaches that give more control of the process to affected stakeholders
61
Data Models
present a formal way of selecting, structuring, and spring the most important details of reality for a given purpose, based on standard conceptualization of spatial entities
62
Basic GIS conceptual level , characteristics needed to be GIS dataset
spatial entities represent standard primitive structures
entities grouped into distinct data themes
Data themes treated as discrete layers
coordinate data explicitly linked to attribute data
63
Spatial entities are represented by standard primitive structures
based on either feature geometry or grid cells
64
Entities are grouped into distinct data themes
should include fundamental related enities like roads or soil types and not combine unrelated enities together. Each theme is stored as a separate dataset
65
Data Themes are treated as distinct layers
GIS data is structured so that GIS software can display one set of feature (or cells) on top of another like layers of trace paper , and we can change the way layers are stacked one on top of the other
66
Coordinate data is explicitly linked to attribute data
the location information about features or cells that we can view as a a map (coordinate data) is linked to the information we have about chararestics or conditions of those features or cells (attribute data) which we can view as a table. This allows us to easily get info about each feature or cell
67
Vector data
based on feature geometry
generally represented as points, lines, or polygons
must only contain one type of feature geometry
each feature acts as a single data unit
each feature may have many different attributes associated with it
conditions within each feature are considered to be homogenous of all attributes
68
Raster Data
based on grid cell concept
represents spatial information as a grid of equally sized cells
each cell has a single value representing single attribute
lines areas represent as groups of adjacent cells having the same value
each cell distance and independent from its neighboring cells, regardless of value
a single homogenous area may consist of many cells
two coordinate pairs (origin + location of entire dataset)
cell size - indicates the extent of each cell (i.e. the area of the earth)
69
Specialized file formats
1. geodatabse
2. GeoTIff
3. Shapefile
70
Attribute domains
defines the possible values that a given attribute may take. helps preserve data quality by avoiding data of the wrong type into an attribute,
71
point vector data
a distance coordinate pair for each point feature
rich attribute information about each feature
72
Line (or polyline) vector data
a distance coordinate pair locating each node and vertex
which coordinate are part of each polyline - the order in which each node or vertex is connected by a line segment
73
Polygon Vector Data
A distance coordinate pair for each vertex
the order in which each vertex is connected by a line segment
74
attribute tables in vector data
contain an entry for each feature in the dataset
75
Raster Attribute Tables
contain only a count of the cells of each value
76
Vector vs. Raster
Vector
- allows for many attributes to be linked to each feature
- allows for high level of control over how features and conditions are represented
- very good for some types of analyses
Raster
- simple data model allows for relatively quick processing times
- good for handling spatially continuous data - many possible attribute values
- the only option for some types of analyses
77
Shapefile
most common file-based for vector data
a single shapefile consists of several separate files
all relationships between these files handled by the GIS software
all these files are needed for a shapefile to function properly
78
raster data other file types
PNG, JFIF, TIFF
79
Geodatabase
store vector, raster, and tabular data together in single relational database - breaks data down into simple tables to avoid repeated data
the computer can identify and return related information across tables , several datasets can access the same information form any given table
80
Relational Database Mangment system
handles connections between datasets and tables rather than the GIS software
81
Benefits of geodatabase
generally able to handle much larger datasets and run processes much more quickly
large complex databases can be disputed to and edited by many users simultaneously
provide other tools that allow us to define relationships among datasets
82
Disadvantages of Geodatabase
not supported by all software programs, sharing a single data set is more complicated
- data stored on server --- copied to local system ---- data stored locally --- stored copy displayed on local system
83
Data Services
Data stored on sever ----- displayed to local system
3 types
84
Feature services
full functional vector data. Users may be able to extract feature, perform, analysis, and change symbology
85
Image services
full functional raster data. Users may be able to extract features, perform analysis, and change symbology to some degree
86
Map Services
data for display only. Users cannot extract features, perform analysis or change symbology
87
Benefits of data service
maps are updated automatically when the original data are updated
require less storage space on local system
88
Disadvatanges
data may change or be removed when you do not expect it
may have limited functionality
89
Embedding
creates a copy of the content within the working file (e.g. adding a image to word processing doc)
editing data this embedded in a doc will only change the data in that document
90
Referencing
does not create a copy of the content but links it from a separate file
ArcGIS use referencing method
editing data referenced by a file will affect any other docs that reference it as well.
91
Benefits of referencing data
keeps file size down, allows maps to be updated automatically when data is updated, allows us to link and stream data remotely over internet
92
File path
a small piece of code that tells the computer where to find a specific data resource within its file system
of dataset is not at the location given by the file path it will not be displayed
93
Absolute paths
start at the top of the hierarchy regardless of where the files are in relation to each other
used by ArcGIS
C:/ProjectsDirectory/LocalGeodatabase/dataset_b
94
Relative Path
always start from the referring file
../LocalGeodatabase/data_b
the ... tells computer to move up one level in the hierarchy
95
relative vs. absolute
if data is NOT moved then an absolute path WILL point to it even if the refereeing file is moved
If BOTH the data and the referring file are moved a relative path will point to the data as long as the file structure between the referring file and data remains the same
96
Map scale
indicated the size relationships between a representation and the thing it represents
97
Representative Fraction
a simple ratio between the map distance and ground
map distance/true distance
map distance always expressed first and always equal to one
98
verbal scale
converts the numerator and denominator of the RF to different units for easier interpretation
99
scale bar
represents the relationships between map distance and ground distance
100
small scale
covers a LARGE geographic area, has very small RF, features appear smaller in small scale maps
101
Large scale
covers a SMALL geographic area, has larger RF, features appear larger in large scale maps
102
Point Vector Data detail
distinct coordinate pair for each point feature
103
Polyline (line) data detail
a distinct coordinate pair locating each node vertex
104
polygon data detail
a distinct coordinate pair for each vertex
105
Raster data detail
two coordinate pairs representing the location and the extent of the sheet (origin)
cell size indicates the extent of each cell (i.e. area)
simple attribute data about each cell
106
Minimum Mapping Unit
a size below which features should be excluded or converted to simpler geometry
removes features based on structural priority rather than size
107
Coordinate Data pt2
position on the Earths surface where a thing, event or condition is located using a known coordinate system
108
Attribute data pt 2
nonspatial information about each thing, events, or conditions,
may contain information about the location of a given feature by listing coordinates address etc.
109
Attribute table structure - Record
record - row of the values of all attributes (i.e. popden2010) for a single feature (i.e. Middlesex) and all its appropriate values for area, population, density, region
single feature may only have on record
110
attribute table structure - field
the values of a single attribute for all features are arranged in a column
111
Structured Query Language (SQL)
provides a standard syntax for selecting records based on field values
Format: SELECT * FROM WHERE
