Extrapolation domain analysis (EDA) is a

methodology In its most common sense, methodology is the study of research methods. However, the term can also refer to the methods themselves or to the philosophical discussion of associated background assumptions. A method is a structured procedure for bri ...

for identifying geographical areas that seem suitable for adoption of innovative

ecosystem management Ecosystem management is an approach to natural resource management that aims to ensure the long-term sustainability and persistence of an ecosystem's function and services while meeting socioeconomic, political, and cultural needs. Although indi ...

practices on the basis of sites exhibiting similarity in conditions such as climatic,

land use Land use is an umbrella term to describe what happens on a parcel of land. It concerns the benefits derived from using the land, and also the land management actions that humans carry out there. The following categories are used for land use: fo ...

and

socioeconomic Economics () is a behavioral science that studies the Production (economics), production, distribution (economics), distribution, and Consumption (economics), consumption of goods and services. Economics focuses on the behaviour and interac ...

indicators. Whilst it has been applied to water research projects in nine pilot basins, the concept is generic and can be applied to any project where accelerating change being considered as a central development objective. The outputs of the method thus far have been used to quantify the global economic

impact Impact may refer to: * Impact (mechanics), a large force or mechanical shock over a short period of time * Impact, Texas, a town in Taylor County, Texas, US Science and technology * Impact crater, a meteor crater caused by an impact event * Imp ...

of implementing particular innovations together with its effect on

water resources Water resources are natural resources of water that are potentially useful for humans, for example as a source of drinking water supply or irrigation water. These resources can be either Fresh water, freshwater from natural sources, or water produ ...

. The research has stimulated members of several of the Challenge Program for Water and Food projects to explore potential areas for scaling out. Such is the case of the Quesungual

agroforestry Agroforestry (also known as agro-sylviculture or forest farming) is a land use management system that integrates trees with crops or pasture. It combines agricultural and forestry technologies. As a polyculture system, an agroforestry system c ...

system in

Honduras Honduras, officially the Republic of Honduras, is a country in Central America. It is bordered to the west by Guatemala, to the southwest by El Salvador, to the southeast by Nicaragua, to the south by the Pacific Ocean at the Gulf of Fonseca, ...

, which is moving towards new areas in parallel with areas identified by the EDA method. EDA is a combined approach that incorporates a number of

spatial analysis Spatial analysis is any of the formal Scientific technique, techniques which study entities using their topological, geometric, or geographic properties, primarily used in Urban design, Urban Design. Spatial analysis includes a variety of techni ...

techniques. It was first investigated in 2006, when it was applied to assess how similarity analysis can be used to scale out research findings within seven Andes pilot systems of basins. The method developed further the research around Jones' 'Homologue' analysis by incorporating socio-economic variables in the search for similar sites around the Tropics. It has since been used to evaluate ‘ Impact pathways’ and Global Impact Analysis.Bouman, Bas, Simon Cook, Boru Douthwaite, Claudia Ringler, Jorge Rubiano, and Tingju Zhu. June 2007. “Impact Potential of the “Temperate and Tropical Aerobic Rice (STAR) in Asia”. Internal document prepared by the CPWF Impact Project for the External Review team. 'Homologue' was developed to determine the similarity of climatic conditions across a geographical area to those exhibited by the pilot site; the pixel resolution at which this is processed is 2.43 arc minutes, or 4.5 km at the equator. To derive the extrapolation domains, Bayesian and frequentist statistical modelling techniques are used. The weights-of-evidence (WofE) methodology is applied; this is based largely on the concepts of Bayesian probabilistic reasoning.Bonham-Carter, GF. 2002. Geographic information systems for geoscientist: Modelling with GIS. In: Merriam DF, editors. Computer Methods in the Geosciences. New York: Pergamon/Elsevier; 302–334. In essence, statistical inference is based on determining the probability of target sites adopting the change demonstrated in pilot areas. The assumption is that a collection of training points will, in aggregate, have common characteristics that will allow their presence in other similar sites to be predicted. It is based on the collection of factors (used to create evidential theme data layers) that prove to be consistent with successful implementation at pilot sites and assumes that if target sites exhibit similar socio-economic, together with climatic and landscapes attributes to pilot sites, then there is strong evidence to suggest that out-scaling to these sites will succeed.

References

*Jorge E. Rubiano M., Simon Cook, Maya Rajasekharan & Boru Douthwaite (2016). A Bayesian method to support global out-scaling of water-efficient rice technologies from pilot project areas. Water International {{DEFAULTSORT:Extrapolation Domain Analysis Ecosystems Bayesian statistics