The methodology used to construct tree structured rules is the focus of this monograph. Unlike many other statistical procedures, which moved from pencil and paper to calculators, this text's use of trees was unthinkable before computers. Both the practical and theoretical sides have been developed in the authors' study of tree methods. Classification and Regression Trees reflects these two sides, covering the use of trees as a data analysis method, and in a more mathematical framework, proving some of their fundamental properties.

Classification and regression trees

A doubling in global food demand projected for the next 50 years poses huge challenges for the sustainability both of food production and of terrestrial and aquatic ecosystems and the services they provide to society. Agriculturalists are the principal managers of global useable lands and will shape, perhaps irreversibly, the surface of the Earth in the coming decades. New incentives and policies for ensuring the sustainability of agriculture and ecosystem services will be crucial if we are to meet the demands of improving yields without compromising environmental integrity or public health.

/pdf/agricultural-sustainability-and-intensive-production-1h98l920tu.pdf

Agricultural sustainability and intensive production practices

http://abe.ufl.edu/Faculty/jjones/ABE_5646/Xtra%20files/The%20DSSAT%20Cropping%20System%20Model.pdf

The DSSAT cropping system model

ASREML user guide release 3.0

Global climate change impacts can already be tracked in many physical and biological systems; in particular, terrestrial ecosystems provide a consistent picture of observed changes. One of the preferred indicators is phenology, the science of natural recurring events, as their recorded dates provide a high-temporal resolution of ongoing changes. Thus, numerous analyses have demonstrated an earlier onset of spring events for mid and higher latitudes and a lengthening of the growing season. However, published single-site or single-species studies are particularly open to suspicion of being biased towards predominantly reporting climate change-induced impacts. No comprehensive study or meta-analysis has so far examined the possible lack of evidence for changes or shifts at sites where no temperature change is observed. We used an enormous systematic phenological network data set of more than 125 000 observational series of 542 plant and 19 animal species in 21 European countries (1971–2000). Our results showed that 78% of all leafing, flowering and fruiting records advanced (30% significantly) and only 3% were significantly delayed, whereas the signal of leaf colouring/fall is ambiguous. We conclude that previously published results of phenological changes were not biased by reporting or publication predisposition: the average advance of spring/summer was 2.5 days decade � 1 in Europe. Our analysis of 254 mean national time series undoubtedly demonstrates that species’ phenology is responsive to temperature of the preceding

/pdf/european-phenological-response-to-climate-change-matches-the-3dr30qvjfp.pdf

European phenological response to climate change matches the warming pattern

A Pascal implementation is given of the data structures described by Lamacraft and Payne (1980).

Statistical Programs for Microcomputers: The Implementation of a Directory for Data Structures

Methods are discussed for producing combined estimates of treatments whose effects can be estimated in more than one stratum of a generally balanced design. The algorithms of Nelder (1968), Wilkinson (1970) and Payne & Wilkinson (1977) provide a method that is specific to generally balanced designs. This method is compared with others that do not assume general balance, namely maximum likelihood and residual maximum likelihood (REML), and its computing requirements are compared with the REML implementation of Robinson, Thompson & Digby (1982).

A Comparison of Algorithms for Combination of Information in Generally Balanced Designs

An introductory course for Genstat 5 release 4

There are many parallels between the methodology of identification keys and diagnostic tables, and the new methodology of expert systems. For example, the standard identification key identifies specimens from a known set of taxa by applying tests sequentially in a hierarchical manner; this structure is identical to that used in the many expert systems that have a simple deterministic hierarchy of questions leading to a conclusion — which in a statistical context might take the form of recommending some form of analysis. Likewise the systems where the conclusion is determined by comparing an observed set of conditions against a theoretical set of rules use a similar method to that employed by the user of a diagnostic table. Even the expert systems where there is a network of nodes of menus or questions have their parallels in the on-line identification systems that have been developed for botanical and other biological work, and some of these on-line systems allow the user to modify the data base of taxonomic information to take account of new information about the taxa, so that the system is able to learn with experience. Consequently work on methods of constructing efficient keys and tables is very relevant also to expert systems.

R. W. Payne

Papers

Statistical Programs for Microcomputers: The Implementation of a Directory for Data Structures

A Comparison of Algorithms for Combination of Information in Generally Balanced Designs

An introductory course for Genstat 5 release 4

Identification Keys, Diagnostic Tables and Expert Systems

The description of experimental designs in information systems