3426midterm Flashcards
which type of attribute distinguishes one from another, like names
nominal
which type of attributes have an order, like small to large
ordinal
what type of attribute has a 0 point, the difference between values makes sense?
interval
what type of attribute has ratios between values that make sense
ratio
what type of attribute describes flow direction, compass direction, or longitude
cyclic
what represents the geographic world as objects with well defined boundaries in otherwise empty space
discrete objects
in what type of data structure is detail about variation within cells lost, and instead are given a single value
raster
in raster format, properties and attributes are applied to the
cells
what type of data structure has points, lines, and polygons
vector
what model doesn’t allow spatial analysis
spaghetti model
what shows relationships using points and nodes
topology
what type of data has a finite number of variables, each one defined at every possible position
continuous
small scale has a ___ area
large
large scale has a ___ area
small
What types of scale are used?
absolute, bar scale, representative fraction
high resolution means that each pixel is a ___ area
smaller
low resolution means that each pixel is a ___ area
larger
what is a reference or base for other measurements, the center of the Earth from which a coordinate system is projected
a Datum
what is the means of representing a spherical surface in a flat surface
map projection
What are the families of map projections
cyllindrical, conic, planar
Distance (absolute/relative), direction, arrangement, orientation, scale, regular, random, clustered, are all ___
geographic patterns
what are some different types of topology
adjacency, connectivity, containment
what is the spread of attributes from one area to another
dispersion
what are different types of expansion/diffusion
contagious expansion, hierarchical expansion, relocation diffusion
what is the time distance decay
the presence decreases as the time and distance increases
intersection, union, and identity are all forms of
overlay
line, point, and polygon are all types of
buffers
remotely sensed images, and digital aerial photos are types of
raster primary data
GPS points, and field survey are all types of
vector primary data
what is data gathered and organized by someone else?
secondary data
what are types of open gis?
OpenStreetMap, CoCoRaHS, Nature’s notebook
what are different types of scanning
flatbed, drum, line
what is the first step of digitizing
map preparation, assign unique identifiers, mark tic locations
what is the second step of digitizing
begin digitizing, registration and transformation
what is the third step of digitizing
ensure the continuity of features across map sheet boundaries
one of a set of ordered xy coordinate pairs that defines the shape of a line or polygon feature
vertex, euclidean geometry
point representing the beginning or ending point of an edge , topologically linked to all the edges that meet there
node
what analysis involves selecting, counting, and selective statistics
simple spatial analysis
what analysis often must link to other software and/or significant programming by user
advanced spatial analysis
what determines attributes from data (not stored in the data)
higher level objects
centroids, point patterns, landscape metrics are all types of
higher lever objects
What is essentially the center of gravity for point distributions, weighted point distributions
centroids
what are the three major types of networks
straight line, branching, circuit
what is used to measure concentration
hoover index
what does a negative hoover index mean
concentrated
what does a 0 hoover index mean
uniform
what does an above 0 hoover index mean
deconcentrated
centroids, central features, standard distance, directional distribution, point density (kernal density) are all types of
higher level point objects
What do these nearest neighbor values mean
R= 1
R=0
R>1
random
“perfectly” clustered
uniform/dispersed
what is the first step of nearest neighbor analysis
find the nearest neighbors
what is the second step of NN analysis
find the distances
What is the third step of NN analysis
find the average NN distance
what is the fourth step of NN analysis
find R =NND(A)/NND(R)
What function shows how similar
G function
what is the exhaustive regular or irregular partitioning of space
tessellation
What is the most common tessellations
squares, from remote sensing: pixel, raster
what is the map of the direction the slope is facing
aspect
what is the statistical measure of how proximate objects are related
autocorrelation
what are the two types of autocorrelation
spatial and serial
what is the creation of a surface from point data and their attributes
surface interpolation
what are types of surface interpolation
thiessen polygons, linear interpolation (trend surface analysis), weighted distance, kriging
what kind of interpolation uses all known sample points to estimate a value at an unsampled location
global
what kind of interpolation uses neighborhood of sample points to estimate
local
what surface takes into account the sun azimuth abd sun zenith
hillshape
What surface has a DEM start, then calculates the flow of accumulation
watershed analysis
what are some types of statistical surfaces
DEM, Isolines, TINs, other rasters
what is a set of polygons that represent the closest area to a point
veroni diagram
what produces edge effects
extrapolation
what tries to create a nonlinear surface that fits through every point in a dataset
spline
what is the z value field in a spline
numerical attribute of points
using a regularized spline, a higher weight means
smoother surface (W= 0-5)
using a tension spline, a higher weight means
coarser surface (W>0)
what takes a weighted local average to interpolate the points
inverse distance weighting
what tells us how much near things are related, a quantitative number
the power in
Weight= 1/distance^power
what measures how different point pairs are
semivariance cloud
if points are similar they have a ___ semivariance
low
what tells us that beyond this distance, the points do not affect the points nearer. (the distance the model first flattens out)
the range in a semivariance cloud
The value that the semivariogram model attains at the range
the sill
what is the partial sill
the sill minus the nugget
what are the outputs of a variogram
prediction map. standard error, quantile map, probability map
what type of kriging does not have a trend
ordinary kriging
what type of kriging has a trend without known model parameters
universal kriging
what type of kriging has a trend with known model parameters
simple kriging
what type of kriging has a binary predictio surface
indicator kriging
what type of kriging has multiple inputs
cokriging
what type of interpolation often results in a more realistic interpolation but estimating missing data values is more complex
nonlinear interpolation
which analysis requires which operations and in what order to be thought out in advance
multifaceted analysis
how many commands does ArcGIS have
7000
multifaceted analysis is not linear, but
iterative
what aids the modeling process bu diminishing the complexity of the task, permits planning in an organized manner, provides documentation
flowcharting
what type of model illustrates existing condition and isolates specific factors to clarify what is going on
descriptive model
what type of model asserts a causal relationship
predictive model
what type of model employs a known causal relationship to engineer a desired result in a specific instance
prescriptive model
what are two types of model perspective
objective (streamflow modeling)
subjective (preserving farmland while allowing urban growth
What are the four major steps in a typical GIS project
- determine objectives and design the model/design the database
- build the database
- perform the analysis
- present the results
what is used to group features for separate mean center computations
the case field
what is constructed from the average x and y values for the input features
the mean center
in mean center computation, what is any numeric field in the input feature class
the dimension field
what creates standard deviational ellipses to summarize the spatial characteristics of geographic features
directional distribution
in directional distrbution and standard distance, the case field is used to
group features prior to analysis
what measures the degree to which features are concentrated or dispersed around the geometric mean center
standard distance
what interpolates a raster surface from points using a two dimensional minimum curvature technique
spline
what spatial analyst tool results in a smooth surface that passes exactly through the input points
spline
T/F IDW can extrapolate values outside of the known range
false
what is the measure of how different points are
semivariance
what does 0 mean on a variogram?
there is no difference
what is the lag distance
how far apart the two points are
what is the space between 0 and the actual semivariance of a pair with lag distance 0
the nugget
what value determines how much of the population would have to be redistributed
hoover index
what is the measure of whether there is a directional difference in the variogram
anisotropy
what projection is best for areas of wide ranges of latitude but poor for areas with wide ranges of longitude
UTM
