Chapter 2 Reading Flashcards
pg 45-77, pg 45-61
aggregated
to combine measurements from one set of spatial units to a
larger unit using a regular or hierarchical scheme, such as adding
county populations to determine the state populations
alpha
a color parameter that defines the opacity or transparency of a
color
bivariate choropleth map
a graduated colors map that compares
the spatial patterns of two different numeric attributes by mixing
two ranges of colors together
categorical data
data that place objects into unranked groups;
examples are land use and geology data
chart map
a map showing several different attributes in chart form,
with one chart for each feature
choropleth map
a map in which each feature, such as a state, is
colored according to the values in a data field
classification
assigning features to two or more groups based on
numeric values in an attribute field
classified
a raster display method that divides values into two or more
groups based on their numeric values
CMYK
a method of specifying color using mixtures of cyan, magenta,
yellow, and black; primarily used in printing and publishing
colormap
a set of defined colors matched to specific image pixel
values, which determines how the image will appear
connotation
a typical emotional reaction elicited by certain colors or
symbols
continuous
data that take on a variety of values and that change
rapidly across a data set, such as elevation
convention
a symbol for mapping that is commonly chosen and
understood to have particular meaning
defined interval
a classification method in which the user specifies a
size range for all the classes
discrete
described data that represent distinct spatial objects such as
wells, roads, or counties
divergent color set
a set of colors with a neutral middle value that
grades to increasingly saturated colors of different hues above and
below
dot density map
a map representing attribute values by a
proportional number of randomly placed dots
dynamic labels
labels determined from an attribute and
automatically placed on a map each time features are drawn and
redrawn
equal interval
a classification method in which the user specifies a
number of classes that have equal size ranges
geometric interval
a classification method that bases the class
intervals on a geometric series in which each class is multiplied by a
constant coefficient to produce the next higher class
graduated color map
a map that divides numeric data from a
polygon feature class into classes based on value and displays the
classes with different colors
graduated symbol map
a map that divides numeric data from a line
or point feature class into classes based on value and displays the
classes with different size or thickness of symbols
histogram
a graph showing the number of values from a data set that
occur in evenly spaced ranges known as bins
HSV
a method of specifying color based on hue, saturation, or value
hue
(in HSV color model) the shade of a color, such as red, green, or
blue, measured on a 0 to 360 scale
image
a raster data layer, usually referring to a raster that displays
brightness values, as in a photograph
interval data
values that follow a regular scale but have no natural
zero point, such as degrees Celsius or pH
Jenks method
a way to classify numeric data into ranges defined by
naturally occurring gaps in the data histogram
layer
a reference to a feature class and its associated properties
layer file
a file that stores a pointer to spatial data along with
information on how to display it
layer properties
settings that control how a data set is to be
displayed or viewed
modifiable areal unit problem (MAUP)
statistical and visual
issues caused by aggregating measured data using arbitrary areal
units such as political boundaries
nominal data
values that name or identify an object, such as a street
name
normalize
to divide the values of an attribute field by the total of the
field or by the values in another field
ordinal data
data values that indicate a rank or ordering system
proportional symbol map
a map that displays attribute values with
marker or line symbols that are proportional in size relative to the
value of the feature
quantile
a classification method that divides the data into the
specified number of quantiles so that each class has the same
number of features
ratio data
data having a regular scale of measurement and a natural
zero point, such as precipitation or population
RGB composite
an image displayed by assigning one band of
brightness information to each red, green, and blue color gun in a
display monitor
saturation
(in HSV color model) the intensity of a color measured on
a scale of 0 to 100
slice
to divide the values in a raster into a specified number of even
classes
source data
(1) a spatial data file that provides the features for a map
layer; (2) the original information used to develop a spatial data set
standard deviation
a classification scheme in which the class breaks
are based on the standard deviation values of the data being mapped
stretched
a display method that spreads the data values over the
entire range of symbols available; see also stretch
stretch: to spread the values of an image to cover the entire range of
symbols available, often supplemented by ignoring the tails of the
distribution; see also stretched
style
a collection of map symbols and colors that are stored together
and used together
thematic raster
a raster that contains categorical or nominal data
values, such as land use codes or soil types
Tobler’s law
measurements taken at locations close together are more
likely to be similar than measures taken at locations further apart
unique values map
a map in which each attribute value is assigned
its own symbol
value
(in HSV color model) the darkness or lightness of a color on a
scale of 0 to 100
