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appropriate scales according to visualization qualitative or quantitative data. When a
quantity type of data is selected than the predefined color scales of tones based on one color
with different saturation will be automatically offered in ArcGIS. This offer is
cartographically correct. However, the user can make mistakes here because bad choice
scales are also offered. This mistake of choosing wrong color ramp for expression quality or
quantity is represented on Fig 1. This map visualizes the different six weeks of the student
vacation in the Czech Republic. This qualitative phenomenon is correctly expressed with
different tone of the color (yellow, orange, light blue, green, dark blue and violet) for every
week on the upper map. Wrong usage of color for expression of six weeks by graduated
color ramp (colours from yellow to brown) is in the map on top in Fig. 1. This graduated
color ramp can be used only for quantitative data. Light color (yellow) expresses small
value, dark color (brown) expresses big value. The week of vacation is not small or big
value.
Fig. 1. Example of bad use of color ramp for qualitative data - wrong map (up) and correct
map (bottom)
In developing an intelligent system, there are two related sets of problems. Transformation
of existing cartographic practice into rule-based knowledge stands the first and the second is
to guide the system through the map-making task. The knowledge in the domain is encoded
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