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GUILD MEMBERS are familiar with Archer Software's GenMap UK and
the Surname Atlas CD-ROM. GenMap UK is a general purpose mapping
utility, adept at mapping a variety of one-name study data which
can be geocoded with its comprehensive gazetteer. The Surname
Atlas, on the other hand, is limited to performing queries,
summarizing data and mapping the 1881 Census. The most recent
revision of GenMap UK (2.2 January 2007) incorporated a few bug
fixes, extended the gazetteer to recognise additional census
division names and built in the ability to geocode by map
reference. Despite the powerful search features built into the
Surname Atlas, have you ever found yourself saying .I wish I
could do......? Well, it is possible to extend the features and
functionality of the Surname Atlas through GenMap UK. By
integrating the features of both programs you can create
graphics that would not be possible when the programs are used
alone. Additionally, the ability to map by map reference opens
up a new range of mapping possibilities for GenMap. Let.s begin
with the Surname Atlas's capability to export its tables (the
.Copy table. command). Most users apply this function to print
reports of their search results. However, why not paste it into
Excel, and save it as a db4 file? This file can in turn be
imported into GenMap. What are the advantages of this process?
First, your maps can be viewed full screen in GenMap in contrast
to the restrictive window provided with The Surname Atlas. All
the same mapping options are available in GenMap, but they are
generally more flexible. For example, the labeling feature in
the Surname Atlas is an all-or-nothing option, whereas in GenMap
you can selectively label symbols or areas. You also have much
more flexibility in terms of map annotation and in structuring
the title.
In addition to floodfill maps, GenMap gives you
the option of displaying maps with proportional circles. The
Surname Atlas is restricted to
floodfill maps. While this may seem a minor point, consider
that each mapping style has its particular strength and can
normally do only one thing well. Floodfill maps have the
advantage that it is easy to interpret values as each colour
represents a range of values. What it doesn't do as well is give
as good a sense of spatial distribution. In contrast,
proportional symbol maps portray distributions well, but the
values are more difficult to interpret.
Advanced query: An illustration: an
advanced query of the Surname Atlas for all names containing the
*thorpe element produces a table with 292 surnames, including
18,921 individuals. Both maps (Figures 1 and 2 ) tell the same
story but clearly emphasize different elements of the
distribution. GenMap will also allow you to analyze the
distribution with a greater level of sophistication. Figures 1
and 2 display the distribution as a ratio /100,000. But what is
a significant value? Colin D Rogers addressed this issue in
The Surname Detective: Investigating Surname Distribution in
England Since 1086 (P.21). Rogers suggested using the
Banwell Index to measure the concentration of a surname within a
restricted geographic area. A Banwell index of one (1) would
tell us the surname was just as concentrated in the smaller
geographic region (in this case a Poor Law Union) as it is at
the national scale. A value of two (2), on the other hand, would
tell us the surname was twice as concentrated at the local
level. You may be thinking that makes perfect sense, but it
sounds like a difficult exercise. In, fact it is rather easy
using Excel and Gen- Map. When a search is performed by the
Surname Atlas it tells us the value per/ 100,000 for each
geographic unit. It also gives us the same value at the national
scale. In our *thorpe example the national index value is 72.47
per 100,000. The corresponding value for the Pateley Bridge Poor
Law Union is 1,129 per 100,000. If we divide the Pateley Bridge
index by the national index, a Banwell value of 16 results. This
tells us that *thorpe surnames are 16 times as concentrated in
the Pateley Bridge Poor Law Union. Why not create this simple
Banwell Index in Excel before importing the file into Gen- Map?
GenMap isn.t finished! In the symbols property menu you can set
the .minimum event display threshold.. The options start at one
and go up. Therefore you could
 display
only Banwell values above one, two or three times the national
value (see Figure 3 on the next page). At the outset I mentioned
a feature added to GenMap 2.2 that has been largely overlooked.
This is the ability to map by map reference rather than by
place/parish. This means data , any type of data, can be mapped
providing a valid map reference is associated with the
information. Immediately I can think of several practical
applications for the map reference function.
Import places: For example, It could be
employed to import place names containing the *thorpe element.
The place name references can be queried from The Gazetteer of
British Place Names or Genuki's gazetteer. Both sources list the
map reference. The pattern of place references could be compared
with the *thorpe surname map or Banwell index map.
One feature that is absent in GenMap is the
ability to map multiple layers at the same time. However, if you
have access to image software that can handle layers this
shortcoming can be overcome. Using this approach, the *thorpe
place references could be overlaid on the Banwell Index map, or
the *thorpe name map. (see Figure 4)
Have you have ever thought of mapping your
contemporary study members in order to compare the present day
location with the distribution in the 1881 census?* Dr. David H.
Mellor discussed this possibility in the Guild Journal (Vol 8
Issue 8). Due to the proprietary nature of postcode boundary
data, electronic mapping with GenMap is not possible.At some
point in the future postcode data may become freely available.
See New Popular Edition Maps project at: www.npemap.org.uk/ You
don't need to wait. It is possible to map postcode locations
using a postcode centroid (the geographic centre of the
postcode). If you have data in Custodian or another database
program that includes the postcode of study members, why not
include a field for the corresponding map reference? Websites
such as www.streetmap.co.uk/ will accept a query by postcode and
the related map references can be extracted from the site. This
value can be used as the centroid of the postcode. Simply cut
and paste the values into your database and then map your study
by map reference. Similarly, if you have a DNA study it would be
possible to map DNA signatures using GenMap.s
pointmap/polysymbol style based on the postcode centroid of
study members. In summary, both The Surname Atlas and GenMap UK
are valuable stand-alone programs. Used in conjunction with one
another, the ability to analyse distributions or to produce
powerful graphics for websites or one-name study publications
can be greatly enhanced.
* It is possible to map by post code using Earth
plot. See Mapping
by post code
HOWARD MATHIESON
Guild OF One Name Studies Member 4328
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