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Performing longitudinal analysis of socio‐economic change in small‐area spatial units such as census tracts presents several methodological complications and requires significant data preparation. Unit boundaries are revised each census year because of changes in population and delineation methodologies. This limits cross‐year comparison since data are not representative of the same spatial units. To address these problems, we have developed an innovative procedure to reduce error when comparing tract‐level data across census years by apportioning data to the same areal units. This paper describes the methods used to create the Canadian Longitudinal Tract Database. Our procedure is a combination of map‐matching techniques, dasymetric overlays, and population‐weighted areal interpolation. The output is a set of tables with apportionment weights pertaining to pairs of unique boundary identifiers across census years, which can be linked with census data or other data with census identifiers that require longitudinal comparison. Key Messages: Neighbourhood change research is challenged by census boundaries being revised each census year.This paper describes the creation of a longitudinal spatial database of census tracts in Canada, bridging tract‐level data for the 1971–2016 quinquennial censuses to a common set of boundaries.Methodology includes map‐matching, dasymetric overlays, and population‐weighted areal interpolation in order to minimize error when boundaries change over time. [ABSTRACT FROM AUTHOR]

New, free and fast growing spatial data sources have appeared online, based on Volunteered Geographic Information (VGI). OpenStreetMap (OSM) is one of the most representative projects of this trend. Its increasing popularity and density makes the study of its data quality an imperative. A common approach is to compare OSM with a reference dataset. In such cases, data matching is necessary for the comparison to be meaningful, and is usually performed manually at the data preparation stage. This article proposes an automated feature-based matching method specifically designed for VGI, based on a multi-stage approach that combines geometric and attribute constraints. It is applied to the OSM dataset using the official data from Ordnance Survey as the reference dataset. The results are then used to evaluate data completeness of OSM in several case studies in the UK. [ABSTRACT FROM AUTHOR]

ribosort is a computer package for convenient editing of automated ribosomal intergenic spacer analysis (ARISA) and terminal restriction fragment length polymorphism (TRFLP) data. It is designed to eliminate the labourious task of manually classifying community fingerprints in microbial ecology studies. This program automatically assigns detected fragments and their respective relative abundances to appropriate ribotypes. It permits simultaneous sorting of multiple profiles and facilitates direct workflow from TRFLP and ARISA output through to community analyses.ribosort also provides several options to merge repeat profiles of a sample into a single composite profile. By creating a ‘ribotypes by samples’ matrix ready for statistical analyses, use of the package saves time and simplifies the preparation of DNA fingerprint data sets for statistical analysis. In addition, ribosort performs exploratory analysis on the data by creating multidimensional scaling plots that compare the similarity of sample profiles using the statistical softwarer. [ABSTRACT FROM AUTHOR]

The authors have been developing a data preload/prefetch scheme for a linked list structure. In this paper, results of evaluating this preload scheme with benchmark programs requiring frequent pointer operations are reported. This scheme is characterized by the fact that the pointer value of a linked list is preloaded and stored, and a mechanism of providing the pointer value without delay for subsequent instructions is installed inside the processor. While dramatic performance improvement is expected by preloading/prefetching of a pointer value in this scheme, it is feared that a speculative execution using a preloaded pointer value before an update may fail if the linked list structure is modified, which may influence the performance negatively. However, it has been confirmed that in actual programs, such a failure of speculative execution does not occur, so that no performance problem arises. The evaluation results have confirmed a maximum performance improvement of 24.3% and the efficacy of the scheme. © 2002 Scripta Technica, Syst Comp Jpn, 33(3): 21–30, 2002 [ABSTRACT FROM AUTHOR]

The article presents a reprint of the article "Statistical perspectives: all together NOT," by Will G. Hopkins and colleagues, which appeared in "The Journal of Physiology," "British Journal of Pharmacology," and "Microcirculation." It highlights the errors and omissions that can be found in the articles as well as the assertions which are considered to be misleading. It suggests that authors must produce best practice in statistical testing and data presentation.

The article presents a reprint of the article "Reply from Gordon B. Drummond and Brian D. M. Tom," which appeared in "The Journal of Physiology," "British Journal of Pharmacology," and "Microcirculation." The authors discuss their errors concerning the published article and acknowledge the need to improve its data presentation and analysis. Moreover, the plans of the authors to enhance their writing styles and to increase the readership of their next article are also discussed.