GIS quiz Flashcards
Elements of a map and their definitions
TODALSIGS
Title
Orientation
Date
Author
Legend
Sources
Index - list of places on map
Grid - enhanced location specification
Scale - distance
What is magnetic declination
The angle between magnetic north and true north
Three types of scale and which is best for your map
Ratio - 1:1,000
Verbal - “one inch represents one mile”
Graphic - displayed like a “ruler”
Difference between large scale and small scale maps
Large scale - can see lots of details (1/10)
Small scale - zoomed out (1/1,000,000)
Difference between reference and thematic maps
Reference maps are for information about the location of features
Thematic maps show distribution of a specific metric
Difference between quantitative and qualitative maps
Quantitative - espressed as a numerical value
Qualitative - descriptive
Types of reference maps
Political, navigation, topographic,
Types of thematic maps
Choropleth - uses color to showcase a statistic
Dot density - uses dots to showcase statistic
Proportional symbols
Isarithmic
Flow line
Cartograms
What is a map projection
The transformation from the geographic grid to a plane coordinate system
Which properties are distorted because of projection
Angles, areas, directions, shapes, distances
What is an ellipsoid/spheroid/global/geographic coordinate system
Ellipsoid - global coordinates based upon “spherical” coordinates modified to account for imperfect shape of earth
What geographic coordinate system is the most commonly used
Latitude-longitude
What is the Prime Meridian
Imaginary line running longitudinally on the Earth
What is the equator
Imaginary line running latitudinally on the Earth
What 3 datums are you going to deal with the most living in North America
Clark 1866 Datum (NAD27)
World Geodetic System 1984 (NAD84)
Plane Coordinate SYstems
What are the 3 major developable surfaces
Cones, Cylinders, and Planes
What is Tissot’s Indicatrix
Circles plotted on a GLOBE will remain circular
Circles plotted on a MAP will be distorted in area, shape, or angle
What are 3 common definitions/descriptors of data
- facts that are observed
- facts that are measured
- attributes
What are the dimensions of different symbolization forms
- Directly realt
Point
Line
Area
Volume
Time
What is the relationship between symbolization form and scale
Symbolization form is linked directly to scale - the size of symbol reflects magnitude of data
3 Characteristics of data: location, form, time
Location - points, lines, polygons
Form - qual vs quan, disc vs cont, total vs, deriv
Time - time on map, time of data collection, change over time
Difference between qualitative and quantitative data
Numbers vs. description
Difference between discrete and continuous data
Whole number vs. decimal
Difference between total vs. derived data
raw data vs actual after a math equation
MAUP
Modifiable Area Unit Problem - can be used as an analytical tool to help understand spacial heterogeneity and spatial autocorrelation
4 levels of data measurements and differences between them
Nominal - “eye color”
Ordinal - “level of satisfaction”
Interval - temperature
Ratio - height (has true zero)
Common sources of error
Source map error
Data entry errors
Processing errors
Cartographic design errors
Pros and cons of different classification schemes
Manual - customizable
Defined interval - sets specific class range size that user sets
Equal interval - values divded into equal ranges, number of classes set by user
Quantile - applies same number of values in a class, no empty
Natural Breaks/Jenks - Based on natural inherent groupings
Geometric - standardized to ensures each class has approx. same number of values and changes are consistent
Standard Deviation - shows how much values of a feature deviate from mean
3 major areas of map aesthetics
Harmony - relationship between elements
Composition - arrangement of map elements for emphasis
Clarity - ease of readability and recognition
Visual heirarchy and ordering different elments to appropriate visual levels
What is most important thing on map
Thematic symbols
Title, Legend, Symbols, labeling
Basemap - boundaries, sig features
Basemap - water features
Scale, inset map, orientation
Framing
5 levels you will design at each visual level
Generalization - simplified shapes
Symbolization - graphic representation
Color - accents and balance
Layout - composition and alignment
Typography - fonts
What is the optical center
Directly above geometric center
What is the figure ground
A result of contract but in reference to shapes/objects. No figure ground for homogenous representations
What is contrast
Leads to perceptual differentiation, defines what is important
What is balance
Visual impact of arrangement of image units in map frame; impacted most by weight and direction
What is Gestalt theory
The brain will simplify and organize complex images subconsciously
“unified whole
6 Gestalt Laws of Visual Grouping
Proximity - objects close together are grouped
Similarity - objects that look alike are grouped
Continuity - Viewer may extend pattern beyond visual field
Closure - disjoint objects may create single recognizable shape
Figure ground - some objects stand out more
Symmetry
What is text heirarchy
Used to guide readers eye to whatever is most important through size or weight
Different between font and typeface
Font - variation of weights of a typeface (regular, italic, bold)
Typeface - a family of fonts (TNR, Calibri
What is a font
Variation of weights of a typeface
What is a typeface
A family of fonts
What is leading and where would you use it
Line spacing - in titles, paragraphs
What is tracking and where would you use it
Overall space between characters - in sentences
What is kerning and where would you use it
Space between specific characters
Basic anatomy of text
Ascender height
Cap height
Median
Baseline
Descender height
Differece between serif, sans serif, script, and decorative
serif = formal
sans serif = versatile, clean, minimal
script - “old world” vibes
decorative - use sparingly
Serif typeface styles
Old style, transitional, modern, square serif, glyphic
Sans serif typeface styles
Grotesque, geometric, humanistic
What are the 3 primary colors
Red, Yellow, Blue
What are the 3 secondary colors
Orange, green, violet
What are the tertiary colors
Yellow-green, yellow-orange
Blue-green, red-orange
Blue-purple, red-purple
Differences between common color schemes
Monochromatic - same hue, different shades
Analogous - sequential on color wheel
Complementary - opposite on color wheel
Split complementary - on color, each side of opposite
Triad - primary, secondary, or tertiary
Tetrad - 2 analogous and their compliments
Square - perpendicular (cross)
Difference between hue, saturation, and value
Hue - color
Saturation - depth of color
Value - light or dark
Different between tint, tone, and shade
Tint - color + white
Tone - color + gray
Shade - color + black
Difference between data and common color palettes
Diverging - interval data, growth, decline
Sequential - increase in magnitude, ratio, dark=more
Qualitative - each color= specific data point
3 types of color models and differences
RGB - all computers, additive
CYMK - printers, subtractive
HSv (B/L) - values
3 kinds of color blindness/ what colors cant be seen
Deuteranopia - no green
Protanopia - no red
Tritanopia - no blue
Cartography
The science of preparing all types of maps and charts and includes every operation from original survey to final printing of maps
The art, science and technology of making maps, together with their study as scientific documents and works of art.
Map definition
A symbolic representation of selected characteristics of a place
True North
Refers to the North Pole, Never changes
Magnetic North
Refers to Earth’s magnetic field, constantly changes
3 map classifications
Defined by geographic boundaries - small vs large scale
Defined by use - reference vs thematic
Defined by Data Classification - quantitative vs qualitative
Gnomonic
The projection center is at the center of the ellipsoid
Stereographic
The projection center is at the opposite side of the tangent point
Orthographic
The projection center is at infinity
3 types of projections
Conformal - angles are preserved
Equal Area - areas are preserved
Equidistance - distance is preserved between 2 points
Global characteristics lost in 3D to 2D transfer
Shape, area, distance, direction, position
Classification of Projections
- the global characteristic preserved
- geometric approach to construction
- orientation
- interface of projection surface to Earth
