Covariance functions and variograms play a fundamental role in exploratory analysis and statistical modelling of spatial and spatio-temporal datasets. In this paper, we construct a new class of spatial covariance functions using the Fourier transform of some higher-order kernels. Moreover, we extend this class of spatial covariance functions to the spatio-temporal setting using the idea used in...

objectives: the purpose of this study was to compare spatio-temporal gait parameters between elderly and young male subjects. methods & materials: 57 able-bodied elderly (72±5.5 years) and 57 healthy young (25±8.5 years) subjects participated in this study. a four segment model consist of trunk, hip, shank, and foot with 10 reflective markers were used to define lower limbs. kinematic data coll...

introduction temporal and spatial change of meteorological and environmental variables is very important. these changes can be predicted by numerical prediction models over time and in different locations and can be provided as spatial zoning maps with interpolation methods such as geostatistics (16, 6). but these maps are comparable to each other as visual, qualitative and univariate for a lim...

Simple quantitative evaluations of isolate behavioral elements (i.e. frequencies, durations, per cent distributions) are not representative of the whole behavioral structure [1]. As suggested in a landmark paper from Spruijt and Gispen [2], it is only through the evaluation of the inter-relations among behavioral elements that it is possible to explore behavior from very different points of vie...

Spatial data sets do not only contain true information, there is also a certain amount of ‘noise’ associated with the data. The use of these data in spatio-temporal analyses, often results in a sub-optimal representation of reality. Generalising spatial data sets collected at different times may serve the purpose of filtering noise so that spatio-temporal change can be better elucidated. In thi...

In recent years, some investigations have been carried out to examine the assumptions like stationarity, symmetry and separability of spatio-temporal covariance function which would considerably simplify fitting a valid covariance model to the data by parametric and nonparametric methods. In this article, assuming a Gaussian random field, we consider the likelihood ratio separability test, a va...

This study examined the relation of dual-task performance to individual differences on neuropsychological tests. Neuropsychological test scores from 16 young and 16 older participants were simultaneously submitted to a factor analysis that yielded 2 factors (Attention/Executive and Memory) that differed by age and 2 (Motor Speed and Cognitive Status) that did not. Regression analyses revealed t...

Background: Congenital Hypothyroidism (CH) is one of the reasons for mental retardation and defective growth in neonates. It can be treated if it is diagnosed early. The congenital hypothyroidism can be diagnosed using newborn screening in the first days after birth. Disease mapping helps to identify high-risk areas of the disease. This study aimed to evaluate the pattern of CH using the Poisso...

the karnafully is one of the most important rivers due to its profound influence on water chemistry and sediment characteristics. the present study intended to assess the quality of water and sediment from intertidal zone of this river in respect to the pollution index. seasonal water and sediment samples were collected during four seasons (monsoon, post-monsoon, winter, and pre-monsoon) of 201...