Kartographie 7

greek anamorphosis= distortion

-cartograms are attribute data driven map descriptions

-cartograms have explicit correspondence of theme (figure) to gepgraphy (ground)

-symbol location is NOT associated with true location

-physical geography is linearly distorted according to the attribute values (e-g- perceptual space, statistical space)

-Bertin's first visual variable (x,y,z,-location) is implicitly applied in cartograms:

longer distance= more

larger areas= more

2 Types:

linear cartograms (typical: transportation maps)

value-by-area cartograms (Flächenanamorphosen)

-modify geographic space to fit a functional distance

-functional distance:-normally a cost function( time, effort, money...)

-physical space distorted to generate cocentric lines of same cost

-example: travel time cartogram of a populated area

2 basic types:

linear routed cartogram (measured functional distance along fixed(geographic)route

linear unrouted cartogram (maesured functional distance without spatial restrictions)

-conceptual area/size over actual area/size is represented

3 basic types:

-non-contiguous (nicht angrenzend)

e.g. Dorling cartogram

-semi.contiguous

pros:

strong visual impact, intuitively understandable for abruptly changing, discrete phenomena, geographic shapes are preserved,size change can be judged quickly, alternative for graduate symbol maps.

cons: problems recognizing geographic relationships, can disrupt a holistic view/relationship, may need additional explanation

-contiguous (e.g. Dorling population cartograpms:equal people's maps)

distorted geography based on poplation related characteristics, enumeration units stay connected, usefull for small scale maps (e.g. world maps)

multivariate contiguous cartograms: combination with choropleth map information (relative data)

-effective for quantitative information depend on areas -> alternative to choropleth/ graduated symbol map (absolue numbers)

Frau Stirnimaaa

zwei fehlen noch

wie wiiter

und beste ;)