The ALF and DEES projects are based on different but comparable data matrices. The ALF and DEES projects concern only the northern part of France (Domaine d'Oïl). This is the research area considered by A. Dees in his 1980 scriptural atlas: it comprises 85 spatial units (or 'measurement points'). Of the 638 ALF survey points, only 347 correspond to the Domaine d'Oïl. For reasons of direct comparability of the data of Dees and ALF, the Oïl part of the ALF grid was pruned from 347 to 85 points. This pruning was done by superimposing the two grids previously polygonised according to the principles of Voronoi geometry.
This basic 85-point grid was completed as follows:
1,279 working maps. These were extracted by pruning our "big" ALF-data matrix which contains, for 641 points, 1,681 working maps (covering all linguistic categories).
268 scriptural attributes (mostly phonetically relevant). These represent a selection, defined by Dees, from the 298 scriptural attributes published as choropleth maps in his 1980 scriptural atlas.
Shortly after the publication of his 1980 scriptural atlas, Anthonij Dees prepared a similar atlas of more than 200 literary texts from the 12th and 13th centuries. This atlas was finally published in 1987. Unfortunately, the computer data used for the publication was lost. But already in 1983, Dees had 'located' these literary texts according to algorithms he had devised himself. By "localisation" is meant a quantitative comparison of the literary texts with the total of non-literary texts in his 1980 atlas. The lists resulting from these localisation calculations, carried out in 1983 on 222 literary texts, were found by chance in 2006 in the cellars of the University of Amsterdam, transferred afterwards to Salzburg and analysed by us in detail. For reasons of comparability, the search network used by Dees was reduced from 87 to 85 points; the remaining 85 points were assigned the location coefficients calculated by Dees in 1983 for 222 literary texts. These 222 localisation coefficients correspond to the 'working maps' above.
For a detailed description of this triple comparison:
Hans Goebl (2016): The dialectometric interpretation of Anthonij Dees' 'scriptural' atlases, in: Revue de Linguistique Romane 80, 321-368 (with 50 colour maps).