mapping GIS data Flashcards
HSV
hue, saturation, and value, method for discussing the use of color in portraying features on a map
hue
shade of color via wavelength of light
saturation
intensity of color represented as a percentage
value
light or dark represented as a percentage
alpha
opacity of a color used with HSV or RGB method
divergent color set
can show variation around a significant middle value, a multi color gradient
connotation
emotional impact associated with a specific color or symbol, culturally specific
nominal data
name or identify objects portrayed by labels
categorical data
separate features into groups or classes stored as text or codes, represented by a unique values map
ordinal data
categories ranked by some quantitative measure represented by unique values maps or graduated color maps
quantitative data
phenomena that fall on a regularly spaced interval like rainfall or distance
ratio data
has a meaningful 0 point indicating absence
interval data
no meaningful 0 point, anything with negative values, do not support multiplication or division
classified maps
show quantitative data arranged in classes with specific ranges
graduated symbol maps
show quantitative point or line data with increasing symbol size using classes
proportional symbol map
show quantitative point or line data with increasing symbol size with no classes
graduated color/choropleth maps
show quantitative polygon data using colors with varying saturation or value
modifiable arial unit problem (MAUP)
occurs when measurements are being aggregated over arbitrarily defined areas, solved by normalizing data or dot density maps
normalize data
divide each value by a specified variable to avoid MAUP and standardize the data
dot density map
uses randomly placed dots inside each polygon to show the magnitude of a value in the attribute table
chart map
shows multiple attributes using graduated symbols of pie or bar graphs
bivariate choropleth map
shows multiple attributes of two numeric variables with multiple colors
thematic raster
shows features or quantities with the stretched display method or the classified display method
classified display method
divides values into a small number of bins