A Note on Geary's Spatial Contiguity Ratio

A cutting-plane method for contiguity-constrained spatial aggregation

Aggregating areas into larger regions is a common problem in spatial planning, geographic information science, and cartography. The aim can be to group administrative areal units into electoral districts or sales territories, in which case the problem is known as districting. In other cases, area aggregation is seen as a generalization or visualization task, which aims to reveal spatial pattern...

Effects of Spatial and Temporal Contiguity on the Acquisition of Spatial Information

Spatial information comes in two forms: direct spatial information (for example, retinal position) and indirect temporal contiguity information, since objects encountered sequentially are in general spatially close. The acquisition of spatial information by a neural network is investigated here. Given a spatial layout of several objects, networks are trained on a prediction task. Networks using...

Sharpe Ratio Practice Note

A note on deriving weights from pairwise comparison ratio matrices

This paper addresses the Cook and Kress method regarding the use of mathematical programming to derive weights from pairwise comparison ratio matrices. We note that the Cook and Kress formulation has the shortcoming that alternative optimal solutions may occur, which would lead to an infinite set of possible weights. This paper proposes to resolve the problem by formulating a Phase II optimizat...

A note on the sex ratio in anencephalus.

While exploring the association of the sex ratio of stillbirths with cause and duration of gestation, McKeown and Lowe (1951) noted that for anencephalus sex ratio increased with duration of gestation. No explanation was offered for this observation, which is here considered briefly. In Birmingham, during the years 1940-51, 454 stillbirths and 28 infant deaths were attributed to anencephalus (4...