The truth about Ground Truth

This paper presents a critical appreciation of the book edited by Pickles called Ground Truth . It offers a response in defence of GIS, written from the perspective of a quantitative geographer's unavoidably academic view of the strengths and weaknesses of GIS and Ground Truth. In essence, there is a growing need for a multi-partisan approach to improving rather than rubbishing a geoinformation technology that is an expanding global industry of considerable relevance both to the present and to the future.     

A hybrid multi-model approach to river level forecasting

Abstract

This paper presents four different approaches for integrating conventional and AI-based forecasting models to provide a hybridized solution to the continuous river level and flood prediction problem. Individual forecasting models were developed on a stand alone basis using historical time series data from the River Ouse in northern England. These include a hybrid neural network, a simple rule-based fuzzy logic model, an ARMA model and naive predictions (which use the current value as the forecast). The individual models were then integrated via four different approaches: calculation of an average, a Bayesian approach, and two fuzzy logic models, the first based purely on current and past river flow conditions and the second, a fuzzification of the crisp Bayesian method. Model performance was assessed using global statistics and a more specific flood related evaluation measure. The addition of fuzzy logic to the crisp Bayesian model yielded overall results that were superior to the other individual and integrated approaches.     

Algorithms for automated line generalization1 based on a natural principle of objective generalization

Abstract

This article describes a new set of algorithms for locally–adaptive line generalization based on the so-called natural principle of objective generalization. The drawbacks of existing methods of line generalization are briefly discussed and the algorithms described. The performance of these new methods is compared with benchmarks based on both manual cartographic procedures and a standard method found in many geographical information systems.     

Geographic information systems and the BBC's Domesday interactive videodisk

Abstract

The Domesday Project is an ambitious attempt by BBC Enterprises Ltd to present a contemporary snapshot of the United Kingdom in the 1980s on interactive video disk. Two disks are being produced: the first, the local or community disk, consists essentially of information collected by the British people. The second, the national disk, has (amongst other material) a selection of data from both government and quasi-government sources. In total, the disks will hold about 250 Mb vies of digital data. ;is well as some 50000 photographs and around 20 million words of text. The paper introduces the idea of interactive video and the local disk. It then concentrates on methods of access to, and cartographic display of, data on the national disk. We conclude that it is a significant geographical information system which will ultimately form one of the most widely-used data base systems for the foreseeable future.