Borrowing of Land,Security of Tenure and Sustainable Land Use in Burkina Faso

Lack of formal security of land tenure is often cited as a constraint for participatory land management programmes which try to motivate African farmers to grow trees and to realize other improvements in their fields in order to control soil erosion. According to this approach, the borrowing of land would represent an insecure form of land tenure hindering sustainable land use. However, on the basis of a case study in Burkina Faso, this article demonstrates that this is not necessarily so: borrowing arrangements may play a part in avoiding local overload of the carrying capacity and in an efficient distribution of village lands among the farming units. Furthermore, borrowing does not hinder some major intensification techniques of land use which are currently being applied in Burkina Faso. Legal interventions which aim to increase security of tenure and to create favourable conditions for sustainable land use may in fact have the opposite effect.     

EFFICIENT ALGORITHMS FOR CONSTRUCTING PROPER HIGHER ORDER SPATIAL LAG OPERATORS*

ABSTRACT. This paper extends the work of Blommestein and Koper (1992)–BK–on the construction of higher-order spatial lag operators without redundant and circular paths. For the case most relevant in spatial econometrics and spatial statistics, i.e., when contiguity between two observations (locations) is defined in a simple binary fashion, some deficiencies of the BK algorithms are outlined, corrected and an improvement suggested. In addition, three new algorithms are introduced and compared in terms of performance for a number of empirical contiguity structures. Particular attention is paid to a graph theoretic perspective on spatial lag operators and to the most efficient data structures for the storage and manipulation of spatial lags. The new forward iterative algorithm which uses a list form rather than a matrix to store the spatial lag information is shown to be several orders of magnitude faster than the BK solution. This allows the computation of proper higher-order spatial lags “on the fly” for even moderately large data sets such as 3,111 contiguous U. S. counties, which is not practical with the other algorithms.     

F.B.J. Kuiper

Indo-Iranian Journal -     

La légende de Śāntideva

Sans résumé A propos de Amalia Pezzali, {Śāntideva, mystique bouddhiste des VIIe et VIIIe siècles}, Firenze, Vallecchi Editore, 1968. USA $7.80.