Via: uk.ac.portsmouth.csovax; Fri, 18 Dec 1992 09:01:45 +0000
Newsgroups: bit.listserv.ingrafx
Date:         Fri, 18 Dec 1992 09:03:00 GMT
From:         "PORTSMOUTH UNIVERSITY - CARTOGRAPHY DEPT."
              <MAPPAMUNDI@CSOVAX.PORTSMOUTH.AC.UK>
Subject:      Eff of communic

 Hello to all INGRAFX Users,

        You all helped us with our initial proposals, well now the final
proposals have been finished. Please read, enjoy and comment if you so wish.

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The Quantification of the Efficiency of Transmission of Cartographic Data.

        A proposal submitted for consideration in:
        Department of Geography, University of Portsmouth.

                           by

                        PAUL DARLOW,

        Undergraduate, Department of Geography,
                University of Portsmouth.
                (December, 1992)


ABSTRACT
A research proposal bid / grant application for financial assistance in
undertaking research into the efficiency of cartographic communication, using
quantitative methods. In calculating efficiency of communication, it is
necessary to have quantified the content of a map, and a substantial part of
the proposed project is devoted to that task. This document outlines the
financial requirements for undertaking such a research project. The
background to the subject and the aims of the project are described, and
methods of research are discussed. The contribution of the research project
to the wider commercial and academic community is evaluated.

Introduction to Research Field.

        Transmission of data requires that there is an amount of data at an
origin, a transmission method or vehicle, and somewhere to store the
transmitted data. If any of these three components are lacking, data will
remain static and cannot be dynamically transmitted. To quantify the amount
of data being transmitted in a certain situation, it is necessary to be able
to quantify the amount of data at the origin, and also to quantify the amount
of data actually arriving at the destination store.

        Quantification of cartographic images originated in the 1970's, when
various researchers attempted to quantify the amount of information held on a
map. One of the most popular approaches was based around the use of
information theory techniques. Information theory consisted of the use of a
calculated variable of entropy (random disorganisation), to produce a measure
of 'uncertainty'. The amount of information existing in a unit e.g. a map,
could be derived from this measure of 'uncertainty', using the assumption
that as the amount of information increases, so the uncertainty of knowing
what a particular element of information is going to be, will increase.
Therefore, a large amount of information is reflected by a high value for the
measure of uncertainty.

        For a while, there was quite a number of cartographers working in
this field, trying to apply information theory techniques to the
quantification of the map, most notably Sukhov (1970) & Balasubramanyan
(1971). Similar methods, using complexity and uncertainty, to quantify the
amount of information on maps were also developed, by Gokman et al. (1970),
Kadar et al. (1973) and Muehrcke (1973).  Information theory, however, turned
out to be unsuitable for quantifying map data. The theory is based on
increasing the number of discrete items of data, to produce a more complex
surface or structure, which has a higher level of uncertainty. Geographical
data, by definition does not consist of discrete, unconnected items of data,
but instead, a positionally related set of items, or continuous surface.
Information theory was not able to take account of the geographical pattern
of data, just the discrete, independent, attribute data. Robinson & Petchenik
(1975), in looking at information theory, rejected it's direct application to
cartographic communication, 'because of its fundamental concepts'.
Information theory, although rejected by cartographers, became established in
the fields of electrical and electronic communication, where it served a
useful purpose in quantifying signal data.

        If information theory had been valid in its application to
quantifying cartographic data, the quantification of the data transmission
efficiency would have been relatively simple. The total amount of information
captured by the map percipient could have been divided by the total amount of
data contained on the map, to give a ratio, which when multiplied up by 100,
would have given the percentage of information transferred to the map
percipient from the map, otherwise known as efficiency of data transmission.

        With the failure of information theory, the whole field of
quantifying cartographic data was deserted, leaving unrestricted opportunity
for new approaches and techniques, which have been made available by the
ever-onward march of technology. During the time that information theory was
being applied to cartographic data, cartographers and researchers from other
disciplines were busy creating applications and finding uses for the map
quantification techniques which were being studied. Upon the rejection of
these techniques, applications such as quantifying scenic quality from maps
existed without a platform to be based upon. It is probable that some
researchers had their fingers burnt when information theory applied to maps
went up in flames, and this has contributed to the silences which have hung
over map quantification over the last fifteen years.

Aims of Proposed Research Project.

1)      Construction of a methodology to enable the quantification of the
        data content of a map.
2)      Construction of the 'average' map percipient, and his/her
        characteristics and tolerances.
3)      Creation of a research method to calculate the transmission
        efficiency of cartographic data, from the map-maker to the 'average'
        map percipient, based on the total amount of data stored on a map.
4)      Assessment of the cartographic image factors which affect data
        transmission efficiency, to determine which individual types of those
        features will produce low  transmission efficiencies and which types
        will produce high efficiencies.
5)      Evaluation of the suitability of the application of the methodology
        created, to other non-map graphical representations.

Research Design

        Upon embarkation upon the proposed research project, the first task
is to develop a technique or method to quantify the data content of a
cartographic image. It has already been seen that information theory was
rejected because of its failure to take geographical relationships into
account, and so the method to be developed must ensure that the spatial
relationships and the feature data are somehow quantified.

        Firstly tackling the quantification of feature data, it is possible
that a technique could be employed which is similar to that employed by the
Ordnance Survey in looking at measurement of change on maps. The O.S.
quantify changes on their maps by expressing all changes in terms of
house-equivalent units. When the change on a map reaches fifty
house-equivalent units, that map is considered viable for revision.
Different amounts of map features are worth one house-unit, e.g. fifty metres
of motorway, five hundred metres of footpath etc. It would be possible to
employ a similar method to quantify all the information on a map, in terms of
some kind of equivalent unit. Although the equivalation of different types of
features into one standard unit is highly subjective, it could be possible to
produce acceptable equivalents between features. This has been done before in
other non-cartographic applications, e.g. the Blue Whale Unit, and the
Million Tonnes of Coal Equivalent unit. To quantify a complete map would take
many human hours of work in converting all features into a standard unit. It
will be necessary to develop a computerised method for undertaking this
quantification, either based on using digital data from the outset, or by
scanning and recognition of features.

        The quantification of spatial relationships is substantially more
difficult than quantifying map features. Two initial approaches are
recognised at this moment in time, although experimentation with various
concepts may produce a more satisfactory solution. The first approach is to
make the assumption that the blank areas of a map are just as important as
those areas containing feature data. It can be said that a feature not
appearing in one location is of no less importance than that feature
appearing in another location. If this assumption is made, all locations on a
map have equal relationships with all other locations on that map.
Quantification of relationships is then relatively simple, by calculating the
area of the map, dividing by the area of the smallest 'bit' of information on
the map and then relating the answer to the scale of the map. The second
approach is to use a computerised analysis of the distance between each
feature and every other feature on the map. If the computer is set-up to keep
a total of the distances, eventually a final total can be produced, which
could be used to quantify the geographical relationships.

        By marrying the geographical relationship quantity to the feature
quantity, a complete quantification of the map's content becomes a viable
proposition.

        The construction of the 'average' map-percipient was advocated by
Robinson & Petchenik (1975) and will need to involve the construction of a
series of experiments to determine their characteristics and various
tolerances in using cartographic material. Experiments which examine symbol
recognition, distance perception, and other map skills will all need to be
included. A suitably large number of people, of all ages, types and
educational backgrounds, will need to be put through the experiments. The
average scores from the experiments can then be used to build our 'average'
map-percipient.

        To investigate the efficiency of transmission of cartographic data
from the map-maker to the 'average' map-percipient, the amount of the data on
the map produced by the map-maker needs to be calculated using the map
quantification techniques. A small sample of people who fit the 'average' map
percipient's characteristics need to be found, and asked to view the map and
draw their own version of it. However, only one map should be used by the
percipient at a time, either they view the original map, or they draw their
own, but not both simultaneously, to prevent exact copying. Trial and error
with this experiment will decide whether a maximum time limit should be
imposed for the experiment, or perhaps whether a time delay between viewing
and drawing should be introduced. By applying the quantification methods to
the map-percipients drawn version of the map, dividing the resulting value by
the original map's value, and multiplying by 100, a percentage of efficiency
of data transmission can be produced. When all the sample of percipients have
produced their maps and the calculations have been completed, an average
efficiency can be calculated for that individual map.

To assess which cartographic image factors affect data transmission
efficiency, and how they affect it, the previous experiment will have to be
repeated several times, but different versions of the original map will be
used. They should differ in typography, colour, projection, orientation,
symbolisation etc., but only one difference on each map, e.g. only orientation
difference on one map, while only colour difference on another. The sample of
'average' percipients can then work their way through these modified maps.
From the results, the effect of different colour schemes, different symbol
sets etc., on data transmission efficiency should have been obtained.

        To evaluate the suitability of the application of the quantification
methods to other non-map graphical representations, types of representations
will have to be initially selected which appear suitable. Some graphical
representations will obviously not be suited to the application of the
quantification methods which have been developed. When suitable
representations have been selected, trials can be carried out by initially
applying the quantification methods to them, to examine whether further
experimentation is viable. The computer software will almost certainly have
to be modified to handle non-map graphical representations. Any
representations which experience successful trials, can then be examined in
more detail using the 'average' representation-percipient strategy.

Value of Research

        The research project which is proposed here will hopefully achieve
that which was attempted back in the 1970's. The prospects for eventually
achieving the goal of quantification of cartographic data are greater now
than ever before, and are now considered good enough to propose such a
research project as this one. The main difference in undertaking this
research now, as compared with that undertaken in the 1970's, is that we have
the resources of modern technology to do calculations and analyses which
twenty years ago would have been considered unfeasible. The G.I.S. revolution
arrived just too late to be applied to research into quantifying maps.
Several researchers, on reflectance of the work they undertook in the 1970's,
believed that the power which G.I.S. has brought, could have been used
successfully in their search for a suitable quantifying technique.

        So what advantages do the ability to quantify cartographic data and
representations bring? Firstly, if the efficiency of maps was known, it is
probable that the general standard of maps would increase, with highly
efficient maps becoming more commonplace. The demand of the customer would be
for the more efficient maps, therefore encouraging companies who produce
inefficient maps to do better, if they want to stay in business.  Secondly,
the knowledge of how efficiency changes in relation to image features, could
be invaluable to map-producers who are considering a new range of maps, with
innovative new representation features. The creation of the 'average'
map-percipient is also a great asset resulting from this research project.
This 'average' percipient can be put into a wide range of cartographic
situations, to see how he/she responds, or achieves tasks. If the
application of the quantification methods and techniques, to other graphical
representations is successful, a whole new area of calculating efficiency of
graphics becomes possible. It would perhaps be possible to compare different
type of graphical representations through communication efficiency and decide
which type of graphic should be used in a particular situation, for maximum
effect. However, this research project would be considered successful if it
achieved anything new, which the previous researchers into this topic had not
achieved, and it would have at least proved that modern technology is making
available methods which previously have been unobtainable. If this is the
case, a lesson should be learnt, that what cannot be achieved today, should
not be abandoned, but monitored, for the possibility that it can be achieved
in the near future when the technology becomes available.

Financial Requirements for Research Project


One research assistant for 6 months             5000
IBM compatible 486 66Mhz DX2 P.C.               1500
Graphics Scanner                                 800
50 hours SQL / ORACLE Programmer                 500
Off-the-shelf software                           500
Assorted computer accessories                    300
9 pin dot matrix printer                         150
Various maps                                     100
Stationary etc.                                   80
Promotional material for sample percipients       50
Contingency fund (repayable)                     400

TOTAL                                           9380 Pounds sterling


Bibliography

Balusubramanyan, V. (1971) 'Application of information theory to maps', Int.
        Yr.bk. of Cartography 11, 177-181.

Board, C. & Taylor, R.M. (1976) 'Perception and maps: human factors in map
        design and interpretation', Trans. Ins. Brit. Geog. 2, 1, 19-36.

Gokham, V.M. et al. (1970) 'Special & general informative capacity of topical
        maps', Unpublished paper for 5th Int. Carto. Conf. of I.C.A.

Kadar, I. et al. (1973) 'A practical method for estimation of map information
 content', Unpublished paper from Meeting of Commission II, I.C.A., Budapest.

Muehrcke, P.C. (1973) 'Some notes on pattern complexity in map design',
        Unpublished paper for discussion 'Map Design for the User', A.C.S.M.
        ann. meeting.

Robinson, A.H. & Petchenik, B.B. (1975) 'The map as a communication system',
        'The Cartographic Journal', 12, 7-15.

Sukhov, V.I. (1970) 'Application of information theory in generalisation of
        map contents', Int. Yr.bk. of Carto., 11, 177-181.

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                Thanks for reading that little lot!!!

                        PAUL DARLOW
                        Uni of Portsmouth, U.K.

                        HAPPY XMAS!!!
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