1. Generalisation l A map is a two dimensional, scaled down representation of selected geospatial information within a ‘geographical area of interest.’ The size and type of the display medium as well as the map’s intent influences the selection and scaling of information.
1. simplification -> selection -> classification > symbolization

2. SYMBOLIZATION ..how do we choose design options?
Goal: fast and easy communication

3. Visual Design Variables
Shape: the detail or outline of a point
Pattern: regular repetition of shapes
Texture: variation of tones or lines
Orientation: direction of symbol
Size: size in a point, or width of a line
Tone: shade of gray (printing = % of black) 
Colour:    Has three 'dimensions' 
hue: "the visual sensations from wavelengths of light " (e.g red, blue)
chroma:   saturation or intensity = tints,
e.g. pale v solid blue
value:       purity or lightness = shades,
e.g. blue, blue/black
interactive colour wheel

4. Design criteria: 1. Association
Symbols should be 'associated' with their features, physically or by function
Vegetation green
Contours brown
Battlefield
Winter sports
Camping
Railway line
Colour associations: yellow – sun, bright (cheery!) ; blue – water (calm), etc..

5. 1. Association - Points ‘Iconic’ symbols are common
Geometric symbols are more abstract
Letters are not used except:
H  for Hospital,    
P   for Parking and      
i   for Information  (why the 'lower case' 'i' ?)

6. Data downloaded from geogratis.ca

7. Association – points How is population classified
Association – points How is population classified? Nominal, ordinal or interval?

8. Association - Lines
'permanent' physical  features are shown as solid.   e.g. rivers, roads.
Less certain features are shown in broken lines.  e.g. intermittent rivers, trails
Administrative boundaries use a  dot-dash  pattern.

9. Association - lines

10. Association - Polygons / areas?
How to balance area colour/pattern versus boundary outline ?

11. Association - polygons

12. Association – size larger / more important features are symbolised bigger e.g. major river for watersheds

13. 2. Convention
most conventions are based on association e.g. blue for water, while others are less obvious, e.g. light red for urban.

14. Conventional symbols – topographic mapping

15. 3. Qualitative versus quantitative data
Qualitative:   shape, pattern, hue*      e.g. soil types, schools versus churches [nominal / categorical]
Quantitative:     size, tone, chroma, value      e.g. population densities, city sizes
Mixed
Example

16. RED is reserved for importance due to its visual impact
** Red – implies importance: ‘danger’, road signs …

17. Arcmap – categories v quantities menus

18. Qualitative (nominal) data

19. Quantitative (interval) data
-> ?

20. 4. Levels of Contrast
The variables have different levels of visual power. Symbols that belong to the same general group (e.g. hydrographic features) should contrast more strongly with symbols from another group (such as cultural features).
The hierarchy is as follows (most powerful first)
      
Qualitative:      1. hue            2. shape pattern       
Quantitative:    1. size           2. chroma value / tone       
In other words, we might use 'hue' to distinguish water features from cultural, and pattern between different types of water features - lakes, swamps etc..
The variables have different levels of visual power. Symbols that belong to the same general group (e.g. hydrographic features) should contrast more strongly with symbols from another group (such as cultural features).
The hierarchy is as follows (most powerful first)
      
Qualitative:      1. hue            2. shape pattern       
Quantitative:    1. size           2. chroma value / tone       
In other words, we might use 'hue' to distinguish water features from cultural, and pattern between different types of water features - lakes, swamps etc..

21. contrast

22. 5. Visual Hierarchy
Map's purpose determines which visual aspects of the map should be most important.
Important elements should be most visually prominent and highest in the visual hierarchy.
Base information supports the main message and should be lowest in the visual hierarchy.
Scale: country
Emphasis: vegetation distribution
Scale: forest type
Emphasis: parks

24. 6. Other factors: purpose what features are more important in each case …

25. 6. Other factors: cost Colour costs v Monochrome: webpage 1x
photocopy x !
publication x ! !
6. Other factors: cost

26. Summary on symbol design
Symbols – design variables:
Qualitative Quantitative
shape, pattern, size, tone
colour - hue, colour – chroma / value
Symbols – use of design variables:
Association
Convention
Qualitative or quantitative data
Levels of contrast
visual hierarchy
Output purpose and medium