Exploring the Use of Computer Vision Metrics for Spatial Pattern Comparison

Detection of changes in spatial processes has long been of interest to quantitative geographers seeking to test models, validate theories, and anticipate change. Given the current “data-rich” environment of today, it may be time to reconsider the methodological approaches used for quantifying change in spatial processes. New tools emerging from computer vision research may hold particular potential to make significant advances in quantifying changes in spatial processes. In this article, two comparative indices from computer vision, the structural similarity (SSIM) index, and the complex wavelet structural similarity (CWSSIM) index were examined for their utility in the comparison of real and simulated spatial data sets. Gaussian Markov random fields were simulated and compared with both metrics. A case study into comparison of snow water equivalent spatial patterns over northern Canada was used to explore the properties of these indices on real-world data. CWSSIM was found to be less sensitive than SSIM to changing window dimension. The CWSSIM appears to have significant potential in characterizing change and/or similarity; distinguishing between map pairs that possess subtle structural differences. Further research is required to explore the utility of these approaches for empirical comparison cases of different forms of landscape change and in comparison to human judgments of spatial pattern differences.     

Indirect legislation: it is just a question of time

ABSTRACT

This paper focuses on unveiling the underlying conceptions required to elaborate a concept such as indirect legislation, and on possible methods of distinguishing it from direct legislation. Three elements will be put to the test to analyse whether they could be used as distinguishing criteria. Firstly, indirect legislation – like contemporary forms of indirect means to influence behaviours, such as the famous nudges of Thaler and Sunstein – relies heavily on an accurate and complete account of human nature. However, so does direct legislation. Having human psychology as a foundation for legislation leads to several epistemic and evidential issues. Secondly, temporality seems initially to be a likely candidate for the sought for criterion: direct legislation, through punishment, applies after the offence, whereas indirect legislation applies before the offence, precisely in order to prevent it. However, I will show that this understanding needs to be revised. Thirdly, the solution to the difficulty might lie in resolving the issue of what is really the target of influence: what is it that indirect means attempt to modify. At the end of this paper, I will show that the difficulties faced both by Bentham and by contemporary nudge theory seem to imply that a complete re-evaluation of indirect means to influence behaviour is needed.     

Reconstruction of past backyard skating seasons in the Original Six NHL cities from citizen science data

This study conducted linear and change-point analyses of historical trends since 1942 in the length and number of days suitable for skating on backyard rinks in the “Original Six” National Hockey League cities of Boston, Chicago, Detroit, Montreal, New York, and Toronto. Analysis is based on the relationship between ambient air temperatures and the probability of skating, using thresholds identified through the RinkWatch citizen science project. In all cities, coefficient estimates suggest the number of high-probability skating days per winter is declining, with easternmost cities displaying notable declines and growing inter-annual variability in skating days in recent decades. Linear analysis shows a statistically significant decline in Toronto, with a step-change emerging in 1980, after which there is on average one-third fewer skating days compared with preceding decades. The outdoor skating season trends towards later start dates in Boston, Montreal, New York, and Toronto. Future monitoring of outdoor rinks provides an opportunity for engaging the public in identification of winter warming trends that might otherwise be imperceptible, and for raising awareness of the impacts of climate change.     

Insights into Past Ritual Practice at Yikpabongo, Northern Region, Ghana

Varied interpretations have been provided for the figurine mound sites located in Koma Land and in the Mogduri District, Northern Region, Ghana, including that they represent burial mounds or shrines. In particular, the producers or affiliates of the mounds are unknown, as the traditions of the present inhabitants of the archaeological region dissociate themselves from the mounds. Current excavations of the mounds have provided considerable contextual information, leading the excavation team to hypothesise that the mounds are best understood within a shrine context and that the figurines, possibly representing ancestors or other beings, were used in ceremonies aimed at communicating with the supernatural world for healing or other purposes. This article presents the current understanding of these mound sites with particular reference to the 2010 and 2011 excavation seasons and the ethnography of existing groups in the area. Possible future avenues of enquiry are also discussed.     

An Attempt to Determine the Influence of Large Reservoirs on Local Climate

The authors use the method of geographic analogues to predict the influence of the projected Pechora-Vychegda-Kama watershed reservoir on the temperature and humidity of the surrounding territory. On the basis of the climatic influence of the Rybinsk Reservoir, measured by changes in differences of meteorological elements between pairs of stations, the authors expect a 10-km.-wide belt of stable influence around the projected reservoir, with episodic effects in the direction of the prevailing winds up to 30 to 50 km. inland.     

The First Herders at the Cape of Good Hope

It is generally accepted that the earliest livestock and pottery were brought to the southern tip of Africa by Khoi-speaking herders from northern Botswana around 2000 years ago. The archaeological remains of that age, however, show no sign of such a migration. Rather, some evidence points to the arrival of the Khoi in the southwestern Cape toward the end of the first millennium AD. The earliest livestock and pottery, it is argued, probably reached the Cape of Good Hope some 2000 years ago by a process of diffusion. The implications of this model for the current debates on the transition from hunting to herding in southern Africa are discussed.     

Forming and Shaping Pottery Boundaries in Contemporary South-Eastern Botswana

In southern African archaeology, the equation of pottery styles with archaeological ‘cultures’ and their attribution to the antecedents of contemporary ethnic groups has been a common practice for a long time. Ethnoarchaeological studies from other parts of Africa and beyond have shown that the matter is complex and that stylistic and technological boundaries in ceramic distributions can reflect different kinds of social boundaries under different circumstances. To expand on these findings and make them locally relevant, a large-scale ethnoarchaeological study of 41 potters in south-eastern Botswana aims for a better understanding of ceramic technological style and boundary relations. Here, we present and explain only the results concerning the boundaries in the forming and shaping stage of ceramic vessel manufacture. We conclude that learning networks explain the visible boundaries in the technological style of forming and shaping pots in south-eastern Botswana today; language and ethnic affiliation do not. Boundaries in the other stages in the operational sequence of pottery manufacture, such as clay sourcing and preparation, vessel surface treatment and decoration, firing and finishing, will be presented in a series of further publications.