3 messages.-----------------------------------Johnnie ------------------------------------------------------- >Date: Tue, 7 Oct 1997 21:08:42 -0600 >From: Steven R Holloway <[log in to unmask]> >Subject: Re: A very basic question... >----------------------------Original message---------------------------- > >I know this is a fundamental question .... can anyone please define for >me the difference between a 'plan', a 'map' and a 'chart'? Alan MacEachren, in his book How Maps Work (Guildford Press, 1995, pp. 160-162.) "How Maps are Understood." provides one way of making this distinction that is helpful....."MAP AS A RADIAL CATEGORY Lakoff (1987), in combining the ideas of prototypes, family resemblance, fuzzy bounds, and typicality effects, suggests the concept of a radial category. Radial categories have a clearly defined center or prototype. The center of the category is predictable from family resemblance to prototypic members. Non central members are not predictable from prototypes, but, according to Lakoff, are motivated by family resemblances to them. By "motivated," Lakoff seems to mean that there is a cognitive economy in recognizing similarity on some criteria (e.g., appearance, function, etc.) between the potential category member and the central prototype. For maps, we are motivated to consider a contour plot of braincell activity (see Figure 3.13) to be a map because this allows us to interpret the display as we would a topographic surface, thus immediately "recognizing" peaks and troughs in density of active cells. The category "map" seems to be a clear case of a radial category. Its category space can be defined by two orthogonal axes. One is the grading of mapness due to scale identified by both Downs et al. (1988) and Vasiliev et al. (1990). The other involves map abstraction. John Ganter and I have argued that spatial displays form an abstractness continuum from images to graphics (or diagrams) (MacEachren and Ganter, 1990). typical maps occupy a middle ground along this continuum. Combining the ideas of a prototypic scale and abstractness for maps gives us a map category space within which a variety of spatial depictions can exist (Figure 43.) The fact that "map" is a fuzzy and radial, rather than a precisely defined, category is important because of what a viewer interprets a display to be will influence her expectations about the display and how she interacts with it. Prototypic maps, being at the midpoint of the scale axis of this space, are probably more readily interpreted and more readily accepted as objective depictions (than are maps at the atomic or astronomic extremes because they depict reality at a scale closer to human experience. Considering the other axis, graphs and diagrams are often viewed with some suspicion due to their abstract nature, while images (i.e., photos) are generally accepted as unbiased depictions of what can be seen from a particular vantage point. The prototypic map, lying between the image and diagram extremes, clearly involves some processing, and therefore some potential for bias (but also becomes functional due to this processing). The idea that function is often a defining feature of categories is stressed by Lakoff (1987) and others. A depiction is considered a map if it can function like one (e.g., be used to plan a trip). ............................... Steven R Holloway Cartography and Fine Arts [log in to unmask] http://www.wsal.umt.edu/people/holloway/default.html ------------------------------------------------------------------ >Date: Wed, 08 Oct 1997 09:09:34 +0200 >From: Ditz Robert <[log in to unmask]> >Subject: Re: A very basic question... The following definitions are taken from the Multilingual Dictionary of Technical Terms in Cartography, 1973: Map: A representation, normally to scale and on a flat medium, of a selection of material or abstract features on, or in relation to, the surface of the Earth or of a celestial body. Chart: A map designed primarily for navigation. Plan: A large-scale detailed map or chart. Frequently used to describe very large-scale maps in which the outlines of buildings, roads and other man-made features are shown to scale with little Generalization. In general: Plans are maps with a scale less the 1:10.000, Maps have a scale over 1:10.000, and Charts are maps for Navigation Robert Darius Bartlett wrote: > > ----------------------------Original > message---------------------------- > > I know this is a fundamental question .... can anyone please define > for > me the difference between a 'plan', a 'map' and a 'chart'? > > Is it a question of function? Or is there some more precise > distinction > based on use /contents /stylistic representation? Is there a clear > difference between these forms of cartography, or is one considered > a subset of the others (e.g. are charts and plans simply special > classes > of the map)? > > Thanks! > > Darius > > *************************************************************************** > Darius Bartlett Darius > Bartlett > Department of Geography Roinn na > Tireolaiochta > University College Cork Colaste na hOllscoile > Corcaigh > Cork, Ireland Corcaigh, > Eire > > Phone: (+353) 21 902835 Fax: (+353) 21 > 271980 > E-mail: [log in to unmask] > http://www.ucc.ie/ucc/depts/geography/djb > > --------------------------------------------------------------------------- > This message was transmitted using 100% recycled electrons.... > > *************************************************************************** -- ----------------------------------------------------------------------- Dipl-Ing. Ditz Robert email: [log in to unmask] Institute of Cartography Tel: +43 1 58801 4308 University of Technology Vienna Fax: +43 1 504 86 96 Karlsgasse 11 A-1040 Vienna ----------------------------------------------------------------------- >Date: Wed, 08 Oct 1997 09:16:50 +0200 >From: Ditz Robert <[log in to unmask]> >Subject: Re: A very basic question... Sorry, this must mean: In general: Plans are maps with a scale 1:10.000 or greater, Maps have a scale less than 1:10.000, and Charts are maps for Navigation > In general: Plans are maps with a scale less the 1:10.000, Maps have a > scale over 1:10.000, and Charts are maps for Navigation Robert ----------------------------------------------------------------------- Dipl-Ing. Ditz Robert email: [log in to unmask] Institute of Cartography Tel: +43 1 58801 4308 University of Technology Vienna Fax: +43 1 504 86 96 Karlsgasse 11 A-1040 Vienna -----------------------------------------------------------------------