Progress in the human geography of the Maghreb

Sutton and Lawless review a selection of the prolific literature on the Maghreb's human geography published from the late 1970s onward. The pedigree of the discipline in Maghreb was established by several notable geographers who lived, researched, and wrote there. Augustin Bernard's writings on rural settlement, his atlas, and study of Algeria are still cited. Jean Despois's regional study with Raynal and his work on Tunisia, together with the detailed rural research of Jean Poncet, provides a particularly rich coverage for that country. Jean Dresch's early work on Morocco exemplified an early critique of the contemporaneous uncritical colonial human geography. The Sahara's fascination also inspired pioneering studies by Robert Capot-Rey. The work of these notables and others provided a solid background of geographical literature on the Maghreb to be supplemented, criticized, and challenged by more recent researchers, sometimes pupils of the above individuals, and increasingly North African by birth. The tradition of general texts on the Maghreb has continued, though increasingly with systematic approaches replacing regional appraisals. The geography of the decolonization of the Maghreb by Isnard has been replaced by a study summarizing recent collaborative work by a team of French geographers. The Saharan extensions of the Maghreb states have often been linked in general works, sometimes being juxtaposed against the Maghreb as in the essays offered to Jean Despois. Lawless and Findlay's collaborative study juxtaposes geographical studies of each country's economic development with political scientists' evaluations of their sociopolitical development. This review limits itself largely to geographers and geographical journals, only occasionally including significant works from other subject areas, and to 1977-1978 publications, with a few notable exceptions. The spatial juxtaposition of contrasting approaches to economic development, liberal market economy approaches by Tunisia and Morocco arguably leading to dependency, and centrally-planned strategies by Algeria and Libya resulting in bureaucratic constraints serves to offer the Maghreb as a pertinent case-study region for the applied geographer of developing countries.     

Elimination of Source A and B Errors in p-Median Location Problems

The p-median problem is a powerful tool in analyzing facility location options when the goal of the location scheme is to minimize the average distance that demand must traverse to reach its nearest facility. It may be used to determine the number of facilities to site, as well as the actual facility locations. Demand data are frequently aggregated in p-median location problems to reduce the computational complexity of the problem. Demand data aggregation, however, results in the loss of locational information. This loss may lead to suboptimal facility location configurations (optimality errors) and inaccurate measures of the resulting travel distances (cost errors). Hillsman and Rhoda (1978) have identified three error components: Source A, B, and C errors, which may result from demand data aggregation. In this article, a method to measure weighted travel distances in p-median problems which eliminates Source A and B errors is proposed. Test problem results indicate that the proposed measurement scheme yields solutions with lower optimality and cost errors than does the traditional distance measurement scheme.     

Recursive Algorithm for Determination of Proximal (Thiessen) Polygons in Any Metric Space

A new and recursive algorithm for determining proximal polygons is based on quadtree concepts. The algorithm can use any distance metric, and produces a quadtree of the image of the proximal polygons. This can be converted to vector form, or be incorporated directly into a quadtree-based geographic information system, in order to solve a number of closest-point problems. The algorithm can also produce the Delaunay triangulation, which is the dual of the proximal polygons. Empirically, the running time of the algorithm is proportional to the number of centers raised to the 1.6 power.     

PREHISTORIC FLINT MINES AND THEIR IDENTIFICATION AS SOURCES OF RAW MATERIAL

This paper is a statistical and geological study of the results of analysis of flint from British and West European flint mines, carried out by emission and atomic absorption spectroscopy. Groups of flint specimens were studied from each geographically separate flint mining area. Flints were analysed for a group of easily measured trace elements shown by previous work to be generally present. The ratios between the trace elements form a consistent pattern for each flint mine and statistically valid differences of pattern can be recognized between different flint mines. A geological investigation shows that the measured trace elements may be derived from clay minerals and explains geographical and statistical variation in the composition of flint in terms of its mode of origin in the chalk. An advanced statistical technique allows individual flint specimens of unknown origin to be attributed by their composition to one or other of the identified flint sources. The archaeological implications of this study are discussed.