scholarly journals An Information Theory-Based Approach to Assessing Spatial Patterns in Complex Systems

Entropy ◽  
2019 ◽  
Vol 21 (2) ◽  
pp. 182
Author(s):  
Tarsha Eason ◽  
Wen-Ching Chuang ◽  
Shana Sundstrom ◽  
Heriberto Cabezas
Keyword(s):  
Complex Systems ◽  
Fisher Information ◽  
Spatial Data ◽  
A Priori ◽  
Geographical Area ◽  
Spatial Dynamics ◽  
Geographical Patterns ◽  
Social Ecological Systems ◽  
Natural Means ◽  
Selection Of

Given the intensity and frequency of environmental change, the linked and cross-scale nature of social-ecological systems, and the proliferation of big data, methods that can help synthesize complex system behavior over a geographical area are of great value. Fisher information evaluates order in data and has been established as a robust and effective tool for capturing changes in system dynamics, including the detection of regimes and regime shifts. The methods developed to compute Fisher information can accommodate multivariate data of various types and requires no a priori decisions about system drivers, making it a unique and powerful tool. However, the approach has primarily been used to evaluate temporal patterns. In its sole application to spatial data, Fisher information successfully detected regimes in terrestrial and aquatic systems over transects. Although the selection of adjacently positioned sampling stations provided a natural means of ordering the data, such an approach limits the types of questions that can be answered in a spatial context. Here, we expand the approach to develop a method for more fully capturing spatial dynamics. The results reflect changes in the index that correspond with geographical patterns and demonstrate the utility of the method in uncovering hidden spatial trends in complex systems.

Innovative Approach to Information Search by Example of a Patent Analysis of an Important Substitution Plan

2020 ◽  
pp. 143-157
Author(s):  
Maria A. Milkova
Keyword(s):  
Information Search ◽  
Topic Modeling ◽  
Cognitive Biases ◽  
A Priori ◽  
Import Substitution ◽  
Innovative Approach ◽  
Iterative Search ◽  
Comprehensive Picture ◽  
Priori Information ◽  
Selection Of

Nowadays the process of information accumulation is so rapid that the concept of the usual iterative search requires revision. Being in the world of oversaturated information in order to comprehensively cover and analyze the problem under study, it is necessary to make high demands on the search methods. An innovative approach to search should flexibly take into account the large amount of already accumulated knowledge and a priori requirements for results. The results, in turn, should immediately provide a roadmap of the direction being studied with the possibility of as much detail as possible. The approach to search based on topic modeling, the so-called topic search, allows you to take into account all these requirements and thereby streamline the nature of working with information, increase the efficiency of knowledge production, avoid cognitive biases in the perception of information, which is important both on micro and macro level. In order to demonstrate an example of applying topic search, the article considers the task of analyzing an import substitution program based on patent data. The program includes plans for 22 industries and contains more than 1,500 products and technologies for the proposed import substitution. The use of patent search based on topic modeling allows to search immediately by the blocks of a priori information – terms of industrial plans for import substitution and at the output get a selection of relevant documents for each of the industries. This approach allows not only to provide a comprehensive picture of the effectiveness of the program as a whole, but also to visually obtain more detailed information about which groups of products and technologies have been patented.

scholarly journals Incorporating radiomics into clinical trials: expert consensus on considerations for data-driven compared to biologically driven quantitative biomarkers

2021 ◽  
Author(s):  
Laure Fournier ◽  
Lena Costaridou ◽  
Luc Bidaut ◽  
Nicolas Michoux ◽  
Frederic E. Lecouvet ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Quantitative Imaging ◽  
A Priori ◽  
External Validation ◽  
Data Driven ◽  
Imaging Biomarkers ◽  
Clinical Validation ◽  
Biological Processes ◽  
Imaging Data ◽  
Selection Of

Abstract Existing quantitative imaging biomarkers (QIBs) are associated with known biological tissue characteristics and follow a well-understood path of technical, biological and clinical validation before incorporation into clinical trials. In radiomics, novel data-driven processes extract numerous visually imperceptible statistical features from the imaging data with no a priori assumptions on their correlation with biological processes. The selection of relevant features (radiomic signature) and incorporation into clinical trials therefore requires additional considerations to ensure meaningful imaging endpoints. Also, the number of radiomic features tested means that power calculations would result in sample sizes impossible to achieve within clinical trials. This article examines how the process of standardising and validating data-driven imaging biomarkers differs from those based on biological associations. Radiomic signatures are best developed initially on datasets that represent diversity of acquisition protocols as well as diversity of disease and of normal findings, rather than within clinical trials with standardised and optimised protocols as this would risk the selection of radiomic features being linked to the imaging process rather than the pathology. Normalisation through discretisation and feature harmonisation are essential pre-processing steps. Biological correlation may be performed after the technical and clinical validity of a radiomic signature is established, but is not mandatory. Feature selection may be part of discovery within a radiomics-specific trial or represent exploratory endpoints within an established trial; a previously validated radiomic signature may even be used as a primary/secondary endpoint, particularly if associations are demonstrated with specific biological processes and pathways being targeted within clinical trials. Key Points • Data-driven processes like radiomics risk false discoveries due to high-dimensionality of the dataset compared to sample size, making adequate diversity of the data, cross-validation and external validation essential to mitigate the risks of spurious associations and overfitting. • Use of radiomic signatures within clinical trials requires multistep standardisation of image acquisition, image analysis and data mining processes. • Biological correlation may be established after clinical validation but is not mandatory.

scholarly journals A novel methodology for epidemic risk assessment of COVID-19 outbreak

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
A. Pluchino ◽  
A. E. Biondo ◽  
N. Giuffrida ◽  
G. Inturri ◽  
V. Latora ◽  
...  
Keyword(s):  
Human Mobility ◽  
Risk Index ◽  
A Priori ◽  
Geographical Area ◽  
Central Italy ◽  
Policy Model ◽  
Italian Regions ◽  
Northern Regions ◽  
Seasonal Flu ◽  
Epidemic Risk

AbstractWe propose a novel data-driven framework for assessing the a-priori epidemic risk of a geographical area and for identifying high-risk areas within a country. Our risk index is evaluated as a function of three different components: the hazard of the disease, the exposure of the area and the vulnerability of its inhabitants. As an application, we discuss the case of COVID-19 outbreak in Italy. We characterize each of the twenty Italian regions by using available historical data on air pollution, human mobility, winter temperature, housing concentration, health care density, population size and age. We find that the epidemic risk is higher in some of the Northern regions with respect to Central and Southern Italy. The corresponding risk index shows correlations with the available official data on the number of infected individuals, patients in intensive care and deceased patients, and can help explaining why regions such as Lombardia, Emilia-Romagna, Piemonte and Veneto have suffered much more than the rest of the country. Although the COVID-19 outbreak started in both North (Lombardia) and Central Italy (Lazio) almost at the same time, when the first cases were officially certified at the beginning of 2020, the disease has spread faster and with heavier consequences in regions with higher epidemic risk. Our framework can be extended and tested on other epidemic data, such as those on seasonal flu, and applied to other countries. We also present a policy model connected with our methodology, which might help policy-makers to take informed decisions.

scholarly journals Spatial Dynamics Regarding Geographical Concentration of Economic Activities. Italian NUTS-3 Analysis

2021 ◽  
Author(s):  
Stefano De Falco
Keyword(s):  
Empirical Investigation ◽  
Methodological Approach ◽  
Geographical Area ◽  
Spatial Dynamics ◽  
Agglomeration Economies ◽  
Economic Activities ◽  
Production Sector ◽  
Scientific Debate ◽  
Geographical Concentration ◽  
Italian Regions

AbstractFor several years, the themes concerning agglomeration economies have been approached from different perspectives in the scientific debate, as capable of triggering various positive features. The present research starts precisely where many others arrive, that is, given the value of these externalities, analyzing the spatial distribution of the geographical concentration of economic activities and the related influencing factors. To this end, in this contribution an explanatory investigation is carried out into the spatial dynamics deriving from main productive sectors’ concentration in some Italian regions. The proposed methodological approach is based respectively on the LISA spatial autocorrelation models and on the analysis of non-neighboring clusters to understand if the geographical area of reference and / or the particular production sector are influencing variables. The empirical investigation confirms the presence of a parametric interaction between factors related in some cases on the geographical context and in others on the productive sector.

scholarly journals Counter-Interception and Counter-Exploitation Features of Noise Radar Technology

2021 ◽  
Vol 13 (22) ◽  
pp. 4509
Author(s):  
Gaspare Galati ◽  
Gabriele Pavan ◽  
Kubilay Savci ◽  
Christoph Wasserzier
Keyword(s):  
Information Theory ◽  
Technological Progress ◽  
A Priori ◽  
A Priori Knowledge ◽  
Noise Radar ◽  
Low Probability ◽  
Increasing Demand ◽  
Signal Processors ◽  
Function Information ◽  
Selection Of

In defense applications, the main features of radars are the Low Probability of Intercept (LPI) and the Low Probability of Exploitation (LPE). The counterpart uses more and more capable intercept receivers and signal processors thanks to the ongoing technological progress. Noise Radar Technology (NRT) is probably a very effective answer to the increasing demand for operational LPI/LPE radars. The design and selection of the radiated waveforms, while respecting the prescribed spectrum occupancy, has to comply with the contrasting requirements of LPI/LPE and of a favorable shape of the ambiguity function. Information theory seems to be a “technologically agnostic” tool to attempt to quantify the LPI/LPE capability of noise waveforms with little, or absent, a priori knowledge of the means and the strategies used by the counterpart. An information theoretical analysis can lead to practical results in the design and selection of NRT waveforms.

scholarly journals Political topology of Europe

2019 ◽  
pp. 71-93
Author(s):  
Remigiusz Rosicki
Keyword(s):  
Comparative Analysis ◽  
Civil Liberties ◽  
Geographical Area ◽  
Special Kind ◽  
Research Problem ◽  
Topological Dimension ◽  
Political Actors ◽  
Specific Geographical Area ◽  
Research Questions ◽  
Selection Of

The objective scope of the analysis performed in the text encompasses selected aspects of policy in its topological dimension. The space of policy is understood as both a theoretical construct (a policy field) and relations between the characteristics of political actors and their special kind of geographical co-existence. The following have been recognised as essential characteristics of policymaking: (1) electoral process and pluralism, (2) functioning of government, (3) political participation, (4) political culture and (5) civil liberties. These features can become an object of analysis in the assessment of democratic and authoritarian tendencies in selected countries. The text uses two statistical methods of multidimensional comparative analysis (Ward’s method and k-means method), apart from which use has been made of basic descriptive statistics and a comparative analysis of the values of the parameters of political characteristics. A selection of 40 European countries (EU-28 and 12 other countries) have been subjected to a statistical analysis according to the 2018 data. The main goal of the analysis is to connect facts and characteristics attributed to policy with a specific geographical area. In order to elaborate the objective scope of the research problem, the following research questions have been presented in the text: (1) Which of the characteristics of policy will determine the division of state entities according to a special type of clusters?, (2) Will political characteristics determine the division of particular state entities according to a special type of geographical division? The addressed research questions have been related to the hypotheses subjected to verification in the text.

scholarly journals Spatial Dynamics of Internal Migration Flows of the Skilled and Unskilled in Mexico

2020 ◽  
Author(s):  
Miguel Flores Segovia ◽  
Eliud Silva
Keyword(s):  
Internal Migration ◽  
Census Data ◽  
Relative Concentration ◽  
Spatial Dynamics ◽  
Unskilled Labor ◽  
Geographical Patterns ◽  
Economic Agglomeration ◽  
Skilled And Unskilled Labor ◽  
Migratory Patterns ◽  
Relationship Of

ABSTRACT: The dynamics of the internal migration is a crucial element in the composition of the workforce of a certain region, so its analysis contributes to the better understanding of labor markets and sociodemographic changes in a region. In order to characterize the most recent patterns of migratory flows of skilled and unskilled labor, census data are considered for the periods 1995-2000, 2005-2010 and 2010-2015. The analysis considers different indicators that describe the intensity and relative concentration of interstate migration. Changes in migratory patterns are evident; a lower concentration of internal migration whose effect is more marked for unskilled labor. That is, it is observed that the number of states that play a preponderant role in the redistribution of labor in Mexico has increased. The relationship of domestic labor mobility is evident to the regional transformation as a result of new geographical patterns of location of investment, production and economic agglomeration.

Sign in / Sign up

Export Citation Format

Share Document