Nonlinear Multivariate Spatial Modeling Using NLPCA and Pair‐Copulas

A novel geostatistical modeling approach is developed to model nonlinear multivariate spatial dependence using nonlinear principal component analysis (NLPCA) and pair‐copulas. In spatial studies, multivariate measurements are frequently collected at each location. The dependence between such measurements can be complex. In this article, a multivariate geostatistical model is developed that can capture both nonlinear spatial dependence across locations and nonlinear dependence between measurements at a particular location. Nonlinear multivariate dependence between spatial variables is removed using NLPCA. Subsequently, a pair‐copula based model is fitted to each transformed variable to model the univariate nonlinear spatial dependencies. NLPCA and pair‐copulas, within the proposed model, are compared with stepwise conditional transformation (SCT) and conventional kriging. The results show that, for the two case studies presented, the proposed model that utilizes NLPCA and pair‐copulas reproduces nonlinear multivariate structures and univariate distributions better than existing methods based on SCT and kriging.     

Book reviews

The Geography of Europe's Futures. Ian Masser, Ove Sviden and Michael Wegener, London, Belhaven Press, 1992, 225 pp., £12.99, ISBN 1 85293 231/2 7/5.

Cities and Regions in the New Europe. Mick Dunford and Grigoris Kafkalas (Eds), London, Belhaven Press, 1992, 339 pp., £42.00, ISBN: 1 85293 221 X.

Regional Development and Contemporary Industrial Response: Extending Flexible Specialisation. Huib Ernste and Verena Meier (Eds), London, Belhaven Press, 1992, 256 pp., £35.00, ISBN: 1 85293 214 7.

Understanding Information: Business, Technology and Geography. K. Robins (Ed.), London, Belhaven Press, 1992, 207 pp., £37.50, ISBN: 1 85293 109 4.

Humanising the City? Social Contexts of Urban life at the Turn of the Millennium. Anthony P. Cohen and Katsuyoshi Fukui (Eds), Edinburgh, Edinburgh University Press, 228 pp., £29.50 hb., ISBN 0 7486 0388 3.     

Book reviews

Regions Reconsidered: Economic Networks, Innovation and Local Department in Industrial Countries. Edward Bergman, Gunter Maier and Franz Tödtling (Eds), London: Mansell Publishing Limited, 1991, 312pp.

Travel Sickness: The Need for a Sustainable Transport Policy for Britain. J. Roberts, J. Cleary, K. Hamilton and J. Hanna (Eds), London: Lawrence and Wishart, 1992, 358pp.

Endogenous Development and Southern Europe. G. Garofoli (Ed.), Aldershot: Avebury Press, 1992, ISBN 1 85628 1310, 250pp., £37.50.     

Canadian and Australian farm interest groups

It is not surprising that the organization and behaviour of farm organizations differ depending upon whether they operate in unitary or federal states or in parliamentary or congressional type environment. The question is how different or similar are they and their behaviour in states which are both federal and both parliamentary.

This article examines the variations between Australian and Canadian farm organizations and examines some of the possible explanations for them. Some of the differences stem from the origins of the organizations, others from variations in the two countries’ political institutions or their usages.