SPIDER—an interactive statistical tool for the analysis of spatially distributed data

Interactive statistical graphics are reviewed in the contexts of spatial data and geographical information systems (GIS). GIS provide the user with an active geographical view of the data—a map that can be used as an entry point to the data base. Prototype software—SPIDER—illustrates the possibilities of using statistical graphics as further views of the data, which can be made active and thus provide alternative means of querying the data. These views can be cross-referenced by 'linking'. It is argued that such a system can provide a very rich environment for pursuing exploratory statistical analysis of spatial data.     

Brief Introduction to Papers on Pterosaurs

Brief Introduction to Papers on Pterosaurs     

Modelling landslide distribution on loess soils in China: an investigation

Abstract

Catastrophic landslides are a severe environmental problem on the Loess Plateau of China. In order to establish which slopes are most at risk, their spatial incidence can be modelled using geographical information systems techniques together with a database describing the past landslides. Three modelling strategies, sieve mapping, weighting factors and log-linear modelling, are adopted and compared. It is suggested that the log-linear modelling approach is the most general and makes best use of the available information.     

A New Species of Huaxiapterus （Pterosauria： Pterodactyloidea） from the Lower Cretaceous of Western Liaoning, China with Comments on the Systematics of Tapejarid Pterosaurs

A new species of tapejarid pterosaur, Huaxiapterus coroUatus sp. nov. is erected on the basis of a nearly complete skull and postcranial skeleton from the Lower Cretaceous Jiufotang Formation of Liaoning Province, China. Huaxiapterus coroUatus sp. nov. is characterized by a hatchet-shaped rectangular process on the premaxilla, whose short axis is perpendicular to the anterior margin of the premaxillae. Except for this process, other characters of the skull such as the breadth of the snout between the anterior margin of the nasoantorbital fenestra and the anterior margin of the premaxilla are similar to that of Huaxiapterus jii. Huaxiapterus and a second Chinese tapejarid, Sinopterus, share several unique cranial characters in common with Tapejara and these three genera appear to be more closely related to each other than to other azhdarchoids. The Chinese tapejarids （Sinopterus and Huaxiapterus） have relatively elongate skulls and weakly developed cranial crests and seem to be less derived than Tapejara, with its shorter, deeper skull and large cranial crest. Tupuxuarids （Tupuxuara and Thalassodromeus） have often been associated with tapejarids in the family Tapejaridae, but this relationship is controversial because some phylogenetic analyses have supported the pairing of tupuxuarids with Azhdarchidae. We propose that Tapejaridae be restricted to Tapejara, Sinopterus and Huaxiapterus.     

A syllabus for teaching geographical information systems

The problems in teaching a course on geographical information systems in higher education are reviewed and a possible syllabus that will be most relevant to needs in the United Kingdom is suggested. The syllabus is divided into six major sections relating to the context, cartographic and spatial analytical concepts, their realization in a computing environment, operations, applications and institutional issues. A particular feature is an attempt to maintain a rigid distribution between underlying theory which is relatively stable and its more volatile operationalization on computers. The paper results from a symposium held in Leicester (U.K.) late in 1988 that brought together nine specialists in the held.