Multiscale statistical models for hierarchical spatial aggregation
Data analysis ; Model ; Scale ; Space time ; Spatial aggregation ; Spatial analysis ; Statistics
The AA. introduce a new, general framework for multiscale statistical modeling and inference that is explicitly designed for a broad class of geographic data. The key structural assumption underlying these models is that of a set of hierarchically
defined partitions, corresponding to successive aggregations of an initial data space. The effects of scale associated with such aggregation are captured through a fundamental decomposition of the data likelihood.
The ascending hierarchical classification proceeds by aggregating at each steps the two classes which are, in a certain way, closest. The algorithm can be significantly speeded up if the search for the pair to aggregate can be limited to a suitable
graph. This is what the author achieves. The article first describes the mathematical principles of the method and then follows the algorithm in detail for two imaginary examples with a small number of elements to be aggregated.
Effects of vegetation type on soil resistance to erosion: Relationship between aggregate stability and shear strength
Aggregate ; China ; Erosion control ; Human impact ; Landslide ; Soil erosion ; Soil properties ; Vegetation ; Water erosion
programme. Significant positive linear relationships were found between vegetation, soil aggregate stability and soil shear strength. Vegetation stabilised soil under different hierarchical levels of aggregate organisation, i.e. intra- and inter-aggregate
The AA. investigated the effect of vegetation on both soil aggregate stability and shear strength (through direct shear tests) in former croplands converted to vegetated erosion protection areas within the context of China's sloping land conversion
. As herbaceous vegetation was more efficient than trees in improving aggregate stability, it is suggested that mixtures of different plant functional types would improve soil conservation on slopes, by reducing both surface water erosion and shallow substrate
Method for describing spatial hierarchical structure of urban facilities
The AA. propose a new practical method of describing a hierarchical structure. Based upon empirical observations, they assume that the size of a facility is measured by certain numerical values such as population and that a facility is dominated
by the nearest facility which has a larger size. Under these assumptions, they can represent the hierarchical structure of facilities in terms of a tree graph. They notice from the empirical study that the hierarchical structure of retail stores in Nishinomiya
is more similar to the random hierarchical structure model than to Christaller's model. - (KA)
Hierarchical structures and periodicity in geology and geography
The suggested application of hierarchical systems to geology and geography offers a new view on the evolution of the Earth and a new classification of geosciences. The application of these systems allows the individual fields of geosciences
Towards a hierarchical system of models to coordinate national and regional economic developments in Seventh Pacific conference, Surfer's Paradise, 1981.
A hierarchical change model of business and professional services in the United States
Sectors in business and professional services showed different types of location changes during the study period because they are in different stages of a general hierarchical process, which is conceptualized in a three-stage descriptive model
This paper suggests that a non-hierarchical approach to scalar comparisons may afford a clearer view of environmental relationships operating at different scales. The paper then evaluates the effects of these non-hierarchical, multi-scale