Specific Statistical Procedures Research Articles

Morphometric properties of river basins as indicators of relative tectonic activity – Problems of data handling and interpretation

Morphometric properties of drainage basins, expressed as indices related to their shapes, altitude variability, river networks and stream profiles, are frequently used as proxy information concerning the relative intensity of uplift. Research procedures lead towards division of an area into classes of relative tectonic activity (various rates of surface uplift) and are typically based on compound indices that jointly consider various individual parameters. Given that index approaches are quantitative in nature and comprise large sets of data, their statistical treatment should become an inherent component of the workflow, whereby the results of the statistical analyses should guide the conclusions. However, various data handling issues seem to be seldom addressed or are given inadequate attention. They include selection of variables, correlation analysis, principles of classification in terms of relative tectonic activity, validity of classifications, and criteria for using specific statistical procedures. In this paper we demonstrate the need for rigorous statistical data analysis in a morphometric study, focused on an intraplate mountainous terrain in Central Europe (Orlickie-Bystrzyckie Mountains Block), subject to low or moderate uplift. We analysed 56 drainage basins within the footwall blocks of several prominent fault-generated escarpments. Following literature guidance, the hypsometric and shape characteristics of the drainage basins were considered, whereas clustering and pure-rank based approaches were tested to distinguish classes of relative tectonic activity. The results were compared with indicators of tectonic activity calculated for the escarpments themselves and using DEM-derived terrain attributes indicating enhanced erosion. In addition, we used statistical tests to identify possible lithological influence on the variability of morphometric parameters, which in this study was found to be of secondary importance. Statistical considerations neither allowed for unequivocal classification of drainage basins in terms of relative tectonic activity, nor did they reveal a clear spatial distribution pattern of drainage basins with different morphometric characteristics, typically considered to reflect tectonic forcing. Thus, statistics-based analysis is recommended to avoid the risk of over-interpretation. It is also possible that the likely morphometric signature of tectonically less active settings comprises spatially inconsistent information rather than it is typified by consistently low values of various morphometric parameters.

Nature of Prejudice and Discrimination of People Without Disabilities Towards People with Different Disabilities in Addis Ababa City, Ethiopia

People with disabilities are prevented from accessing health care, and other services, going to school or learning skills, engaging in work or employment, and participating in family and community life due to the inaccessible environment, as well as traditional beliefs, prejudice and discrimination. The main aim of this study was to examine the nature and difference of prejudice and discrimination towards various types of people with disability by preparatory school (grade 11th and 12th) students. The research method used was survey. Two hundred and ninety-three students without disability, who were drawn using multi stage cluster sampling technique, participated in the study. Data were collected using Feeling & Thinking towards People with Disability Scale and Behavior towards People with Disability Scale. The instruments were administered individually. Descriptive statistics, t-test, one way analysis of variance & repeated measurement of analysis of variance were the specific statistical procedures employed to analyze data. As a major outcome of the study; the nature of prejudice towards all four groups of people with disability layed under the range of medium magnitude. Nature of discrimination towards people with physical and intellectual disability falls under the range of moderate. However, discrimination nature was mild towards people with hearing and visual disability. Therefore, nature of prejudice and discrimination vary between different types of people with disability. Consequently based on the findings of the study recommendation were forwarded.

Evaluating Urban Regeneration Policies. Methodological Proposal to Delimitate Experimental and Equivalent Urban Areas

This article analyses a methodological proposal for the delimitation of territorial areas applying a quasi-experimental strategy, comparing areas where projects have been developed based in urban regeneration called “experimental areas” with similar ones without any project, called “equivalent areas”. This methodology is a necessary previous step to analyze the effect of programs about urban regeneration, which will allow subsequently to compare the evolution of similar pairs among themselves (experimental and equivalent areas). Firstly, we explain the underlying objective of delimitation in these territorial areas. Secondly, the methodology used to select the equivalent areas is described. Thirdly, the results are presented, it means, the delimitation of experimental and equivalent areas. Finally, through means of specific statistical procedures, analysis of variance or ANOVA of a factor, the obtained results are validated. The work is focused on Andalusian cities with a population over 100.000 inhabitants in which urban regeneration projects have been implemented.

Information technologies as a means of studying the phenomenon of the individual socialization

The article is devoted to the problems of the use of information technologies (IT) in sociological research, in particular in the process of studying the phenomenon of socialization of the individual. The material consists of three parts, which highlight the essential characteristics of the category of socialization, the current trends in the use of information technology in sociology, and some areas of application of information technology in the process of studying the socialization of the individual.
 Socialization of personality is an important social-pedagogical phenomenon, as the process of human entry into society is often accompanied by problems. Currently, the relevance of intelligence on the problems of socialization has increased significantly, which is largely connected with social changes. The article presents the definition and the main features of the category "socialization", scientific approaches to the interpretation of this concept, as well as a brief overview of the methods of diagnosing the level of socialization of a person.
 The formation of a digital society led to the appearance of computing social sciences and the separation of digital sociology at the beginning of the XXIst century. The peculiarity of the modern period is the use of various sources of secondary sociological information, in particular those which are based on the objective recording of the real behavior of people. The gathering of sociological information takes place with the use of methods of content analysis, analysis of texts and social networks, etc. The vast majority of these methods involve the use of information technology. In addition, methodologies for working with data from Big Data and Data Mining are now widely used to gather and analyze large volumes of heterogeneous data and to generate new useful information on existing or potential interconnections between phenomena on this basis. So, sociology is now focused on the use of new information tools. At the same time, the use of traditional information and communication technologies is still remains of current interest (tools for conducting surveys, statistical analysis programs, etc.), which can significantly reduce the waste of time, reduce the probability of errors of different types, carry out the different methods of analysis.
 In the process of the socialization of a person studying a variety of surveys are widely used, the results of which must be systematized and analyzed. In order to collect such data, it is expedient to use the possibilities of the Internet, which allows reaching a large audience of respondents and reduce the waste of time both by respondents and researchers. Currently online surveys are often used by Google Forms, which provides tools for creating questionnaires of different types of questions, storing received replies, transferring them to spreadsheets in Google Drive, and initial analysis. In the case of increased requirements to the complexity and quality of the questionnaire, as well as the need to reach a large number of respondents, you should turn to specialized web resources, such as SurveyMonkey. The data obtained during the online survey can be analyzed using statistical programs (Statgraphics, Statistica, S-plus, SPSS, Systat, etc.). In particular, such programs provide an opportunity for cluster and factor analysis to classify the phenomena studied and identify the most influential factors.
 Consequently, important steps in the study of the phenomenon of socialization and the level of socialization of the individual are the collection of data (through online surveys using Google Forms) and their analysis using software (office spreadsheets, general-purpose statistical packages or specialized programs aimed at performing specific statistical procedures).

Calibration plot for proteomics: A graphical tool to visually check the assumptions underlying FDR control in quantitative experiments.

In MS-based quantitative proteomics, the FDR control (i.e. the limitation of the number of proteins that are wrongly claimed as differentially abundant between several conditions) is a major postanalysis step. It is classically achieved thanks to a specific statistical procedure that computes the adjusted p-values of the putative differentially abundant proteins. Unfortunately, such adjustment is conservative only if the p-values are well-calibrated; the false discovery control being spuriously underestimated otherwise. However, well-calibration is a property that can be violated in some practical cases. To overcome this limitation, we propose a graphical method to straightforwardly and visually assess the p-value well-calibration, as well as the R codes to embed it in any pipeline. All MS data have been deposited in the ProteomeXchange with identifier PXD002370 (http://proteomecentral.proteomexchange.org/dataset/PXD002370).

Modeling knowledge networks in economic geography: a discussion of four methods

The importance of network structures for the transmission of knowledge and the diffusion of technological change has been recently emphasized in economic geography. Since network structures drive the innovative and economic performance of actors in regional contexts, it is crucial to explain how networks form and evolve over time and how they facilitate inter-organizational learning and knowledge transfer. The analysis of relational dependent variables, however, requires specific statistical procedures. In this paper, we discuss four different models that have been used in economic geography to explain the spatial context of network structures and their dynamics. First, we review gravity models and their recent extensions and modifications to deal with the specific characteristics of networked (individual level) relations. Second, we discuss the quadratic assignment procedure that has been developed in mathematical sociology for diminishing the bias induced by network dependencies. Third, we present exponential random graph models that not only allow dependence between observations, but also model such network dependencies explicitly. Finally, we deal with dynamic networks, by introducing stochastic actor-oriented models. Strengths and weaknesses of the different approach are discussed together with domains of applicability the geography of innovation studies.

Multiparameter analysis of geophysical methods for target detection: The unified geophysical model approach

Void detection is a difficult task for geophysical methods. The main disadvantage is the uncertainty of the final interpretation and the need for verification of the results with direct methods of underground investigation. A good way to reduce this uncertainty, apart from drilling, is through the implementation of more than one geophysical method in the same area. An integrated approach of geophysical methods can be achieved by using multiparameter statistical techniques, such as cluster analysis. Firstly, the effectiveness of multiparameter analysis on synthetic data is studied and then on real data from a controlled test site. In addition, a new approach for the creation of a unified geophysical model (UGM) is suggested to optimize target detection. Finally, the UGM approach is implemented and is evaluated in a real case study for void detection in an urban environment. The UGM offers the integrated information of the geophysical methods that are used without the need for predefined relationships. It is a model resulting from a specific statistical procedure, free of subjective precautions, and easily understood even by nonexperts in geophysics. Finally, it offers an additional tool for the better understanding of the subsurface as far as the difficult task of void detection is concerned.

The Honeypot Randomized Controlled Trial Statistical Analysis Plan

The HONEYPOT study is a multicenter, open-label, blinded-outcome, randomized controlled trial designed to determine whether, compared with standard topical application of mupirocin for nasal staphylococcal carriage, exit-site application of antibacterial honey reduces the rate of catheter-associated infections in peritoneal dialysis patients. To make public the pre-specified statistical analysis principles to be adhered to and the procedures to be performed by statisticians who will analyze the data for the HONEYPOT trial. Statisticians and clinical investigators who were blinded to treatment allocation and treatment-related study results and who will remain blinded until the central database is locked for final data extraction and analysis determined the statistical methods and procedures to be used for analysis and wrote the statistical analysis plan. The plan describes basic analysis principles, methods for dealing with a range of commonly encountered data analysis issues, and the specific statistical procedures for analyzing the primary, secondary, and safety outcomes. A statistical analysis plan containing the pre-specified principles, methods, and procedures to be adhered to in the analysis of the data from the HONEYPOT trial was developed in accordance with international guidelines. The structure and content of the plan provide sufficient detail to meet the guidelines on statistical principles for clinical trials produced by the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use. Making public the pre-specified statistical analysis plan for the HONEYPOT trial minimizes the potential for bias in the analysis of trial data and the interpretation and reporting of trial results.

Early onset versus late onset in Alzheimer’s disease: What is the reliable cut-off?

Objective: As the literature on conventional criteria for discriminating early-onset (EO) from late-onset (LO) Alzheimer’s disease (AD) is sparse and controversial, the aim of this study was to establish a precise age at onset (AAO) criterion, by using a specific statistical procedure, and to describe the clinical characteristics of the two sub-groups. Methods: Admixture analysis was performed to establish the AAO cut-off in a multi-center study including 2000 AD patients consecutively recruited in eight Italian Memory Clinics. None of the patients were taking acetylcholinesterase inhibitors, antipsychoticor anti-depressant drugs. At the first diagnosticvisit, they were administered the Mini Mental StateExamination, the Basic and Instrumental Activities of Daily Living and the Neuropsychiatric Inventorytoassess clinical phenomenology. Results: Using a specific statistical procedure, we established that AAO that discriminated EO-from LO-AD was 66. Compared with the LO-AD group, the EO-AD group showed longer duration of illness and a higher educational level as well as less severe functional impairment and delusions. Conclusions: Differences in sociodemographic and clinical characteristics, such as duration of illness, education and delusion severity, suggested the involvement of different pathogenic processes. Additional studies are needed to further investigate the mechanisms underlying the disorder in the two sub-groups of AD patients.

Psychological Treatment of Recurrent Headache in Children and Adolescents - A Meta-Analysis

Psychologically based interventions such as relaxation training, biofeedback and cognitive-behavioural therapy are increasingly discussed as options for the treatment of migraine and tension-type headache in children and adolescents. In order to determine the state of evidence regarding the efficacy of these treatments, a meta-analysis of randomized controlled studies was conducted. In a comprehensive literature search including data from 1966 to 2004, 23 studies were found meeting the inclusion criteria. Due to the application of the random effects model, generalization of the results is possible. Specific statistical procedures were used to account for a possible publication bias. Significantly more patients improved to a clinically relevant extent (headache reduction > or =50%) in treatment conditions compared with waiting list conditions (high effect sizes). Long-term stability was also confirmed. The analysed treatments lead to improvement (up to 1 year) in headache status in children and adolescents with primary headache. However, more well-designed studies are needed to support and consolidate the conclusions of this meta-analysis and to compare the effects of psychological treatment with those of prophylactic medical interventions (in migraine), to examine potential differences between treatments, to identify moderators of efficacy and to determine effects of treatment on other health-related variables such as quality of life.

Changing Cognitive Structure as a Basis for the "Sleeper Effect"

Let me summarize this general discussion of statistical inference briefly. Area data alone were considered. Three kinds of data resulting from data collection processes were identified. Two kinds of theoretical interpretations of these data were posed, and the remainder of the paper stressed the interpretation in term of aggregates as specified by a particular definition of structure and a theoretical statement of social structure. Four major problems of statistical inference were identified. Various approaches to these inference problems were examined critically. In some cases specific statistical procedures were recommended for use, while in other cases certain difficulties in present procedure were indicated but solutions were not presented. It is the intention of this paper and the research upon which it is based to aid in the development of sound statistical procedures and appropriate statistical inference in the analysis of area data. Illustrative computations of all these procedures are available in the author's unpublished doctoral dissertation. Manuscripts are in preparation which will bring these computations to the attention of a wider audience and thereby encourage the use of more appropriate statistical methods in studies analyzing area data.