This paper proposes an original approach for comparing cadastral management systems, more specifically, the conceptual modeling used to spatially represent vertical divided co-ownership (usually equivalent to the condominium). The comparison is based on the ISO 19152 Land Administration Domain Model (LADM) specification, an international standard recently adopted by ISO. The LADM comparison is applied between Quebec (Canada) and Alsace Moselle (France) condominium units. Specific attention is paid to the third geometric dimension of the spatial representation used in each jurisdiction. The study includes the creation of LADM layouts for condominium units in Quebec and Alsace Moselle and a comparative analysis. The paper discusses the advantages and limitations of using LADM layouts to undertake such comparisons and gives advices to produce similar analysis for others cadastral systems.
LADM schematization certainly made the comparison between Quebec and French condominium units easier, more concise and clearer. The formal description of common set of concepts and terms such as proposed by LADM allows us to quantify the similarities and differences, and potentially move towards the ¡°automatic¡± creation of a matching file between both systems. One of the main advantages is the graphical views resulting from the schematization process that permit visual comparison where both systems can now be compared side by side, class by class, attribute by attribute. The use of the LADM specification is, however, not evident and requires quite a few skills in data modeling. The LADM documentation is somewhat technical and lacking in official definition. It required time to comprehend the documentation, and some LADM classes, attributes or relationships are ambiguous and still difficult to match with both systems.
