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Open Access
Article
Publication date: 10 August 2022

Jie Ma, Zhiyuan Hao and Mo Hu

The density peak clustering algorithm (DP) is proposed to identify cluster centers by two parameters, i.e. ρ value (local density) and δ value (the distance between a point and…

Abstract

Purpose

The density peak clustering algorithm (DP) is proposed to identify cluster centers by two parameters, i.e. ρ value (local density) and δ value (the distance between a point and another point with a higher ρ value). According to the center-identifying principle of the DP, the potential cluster centers should have a higher ρ value and a higher δ value than other points. However, this principle may limit the DP from identifying some categories with multi-centers or the centers in lower-density regions. In addition, the improper assignment strategy of the DP could cause a wrong assignment result for the non-center points. This paper aims to address the aforementioned issues and improve the clustering performance of the DP.

Design/methodology/approach

First, to identify as many potential cluster centers as possible, the authors construct a point-domain by introducing the pinhole imaging strategy to extend the searching range of the potential cluster centers. Second, they design different novel calculation methods for calculating the domain distance, point-domain density and domain similarity. Third, they adopt domain similarity to achieve the domain merging process and optimize the final clustering results.

Findings

The experimental results on analyzing 12 synthetic data sets and 12 real-world data sets show that two-stage density peak clustering based on multi-strategy optimization (TMsDP) outperforms the DP and other state-of-the-art algorithms.

Originality/value

The authors propose a novel DP-based clustering method, i.e. TMsDP, and transform the relationship between points into that between domains to ultimately further optimize the clustering performance of the DP.

Details

Data Technologies and Applications, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2514-9288

Keywords

Open Access
Article
Publication date: 13 February 2024

Daniel de Abreu Pereira Uhr, Mikael Jhordan Lacerda Cordeiro and Júlia Gallego Ziero Uhr

This research assesses the economic impact of biomass plant installations on Brazilian municipalities, focusing on (1) labor income, (2) sectoral labor income and (3) income…

Abstract

Purpose

This research assesses the economic impact of biomass plant installations on Brazilian municipalities, focusing on (1) labor income, (2) sectoral labor income and (3) income inequality.

Design/methodology/approach

Municipal data from the Annual Social Information Report, the National Electric Energy Agency and the National Institute of Meteorology spanning 2002 to 2020 are utilized. The Synthetic Difference-in-Differences methodology is employed for empirical analysis, and robustness checks are conducted using the Doubly Robust Difference in Differences and the Double/Debiased Machine Learning methods.

Findings

The findings reveal that biomass plant installations lead to an average annual increase of approximately R$688.00 in formal workers' wages and reduce formal income inequality, with notable benefits observed for workers in the industry and agriculture sectors. The robustness tests support and validate the primary results, highlighting the positive implications of renewable energy integration on economic development in the studied municipalities.

Originality/value

This article represents a groundbreaking contribution to the existing literature as it pioneers the identification of the impact of biomass plant installation on formal employment income and local economic development in Brazil. To the best of our knowledge, this study is the first to uncover such effects. Moreover, the authors comprehensively examine sectoral implications and formal income inequality.

Details

EconomiA, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1517-7580

Keywords

Open Access
Article
Publication date: 25 January 2022

Pilar Beneito and Óscar Vicente-Chirivella

The autonomous governments of two regions in Spain established mobile bans in schools as of the year 2015. Exploiting the across-region variation introduced by such a…

19800

Abstract

Purpose

The autonomous governments of two regions in Spain established mobile bans in schools as of the year 2015. Exploiting the across-region variation introduced by such a quasi-natural experiment, this study aims to perform a comparative-case analysis to investigate the impact of this non-spending-based policy on regional Programme for International Student Assessment (PISA) scores in maths and sciences and bullying incidence.

Design/methodology/approach

The authors apply the synthetic control method and diff-in-diff estimation to compare the treated regions with the rest of regions in Spain before and after the intervention.

Findings

The results show noticeable reductions of bullying incidence among teenagers in the two treated regions. The authors also find positive and significant effects of this policy on the PISA scores of the Galicia region that are equivalent to 0.6–0.8 years of learning in maths and around 0.72 to near one year of learning in sciences.

Originality/value

To the best of the author’s knowledge, this is the first empirical study analysing the impact of mobile phone bans in schools on bullying cases, exploiting variation across regions (or other units), years and age intervals. Besides, the scarce formal evidence that exists on the consequences of the mobile phones use in students’ academic achievement comes from a micro perspective, while the paper serves as one more piece of evidence from a macro perspective.

Details

Applied Economic Analysis, vol. 30 no. 90
Type: Research Article
ISSN:

Keywords

Open Access
Article
Publication date: 30 August 2022

Nicolene Hamman and Andrew Phiri

The purpose of the study is to evaluate whether nighttime luminosity sourced from the Defense Meteorological Satellite Program-Operational Linescan System satellite sensors is a…

531

Abstract

Purpose

The purpose of the study is to evaluate whether nighttime luminosity sourced from the Defense Meteorological Satellite Program-Operational Linescan System satellite sensors is a suitable proxy for measuring poverty in Africa.

Design/methodology/approach

Our study performs wavelet coherence analysis to investigate the time-frequency synchronization between the nightlight data and “income-to-wealth” ratio for 39 African countries between 1992 and 2012.

Findings

All-in-all, the authors find that approximately a third of African countries produce positive synchronizations between nighttime data and “income-to-wealth” ratio and hence conclude that most African countries are not at liberty to use nighttime data to proxy conventional poverty statistics.

Originality/value

In differing from previous studies, the authors examine the suitability of nightlight intensity as a proxy of poverty for individual African countries using much more rigorous analysis.

Details

African Journal of Economic and Management Studies, vol. 14 no. 1
Type: Research Article
ISSN: 2040-0705

Keywords

Open Access
Article
Publication date: 24 February 2021

Bowen Yang, Liping Liu and Yanhui Yin

Legislation plays a vital role in solving carbon emissions reduction and climate change issues. China began to implement a low-carbon economic policy in 2010, but the effect of…

1439

Abstract

Purpose

Legislation plays a vital role in solving carbon emissions reduction and climate change issues. China began to implement a low-carbon economic policy in 2010, but the effect of the policy needs to be evaluated. Accordingly, this paper aims to discuss China’s low-carbon policy through exploring the following two questions, namely, whether the policy effect reaches the expected goal and whether the policy effects will balance economic development and emission reduction. Then, the paper puts forward suggestions for the improvement of China’s low-carbon policy.

Design/methodology/approach

This paper is organized around three distinct aspects of policy effect evaluation. This paper uses the synthetic control method to construct a policy effect evaluation model and conducts a quasi-natural experiment. The paper selects annual panel data from 2003 to 2015, which is selected from 33 provinces. A comparative analysis of carbon dioxide emissions, energy consumption and economic development between Hubei Province and Liaoning Province.

Findings

The results reveal that the implementation of the low-carbon pilot province policy in 2010 has a significant impact on the emission reduction effect of Liaoning Province, but the impact on the emission reduction effect of Hubei Province is not significant. The carbon emission trading system implemented in 2012 has reduced the emission reductions in Hubei Province and Liaoning Province has achieved better emission reduction effects after the implementation of this policy. After the implementation of the policy, the economic development of Hubei Province has been improved, but it has not brought help to the economic development of Liaoning Province. These findings provide new insights into the use of an emissions trading system for improving economic development and ultimately facilitate the attainment of the broader goal of sustainability.

Originality/value

This paper proposes an innovative policy effect evaluation method by considering the status of unit gross domestic product, fixed asset investment in the energy industry, energy consumption, emission reduction technology innovation and other evaluation indicators. This paper contributes to broadening current methods of policy effect evaluation in China.

Details

International Journal of Climate Change Strategies and Management, vol. 13 no. 1
Type: Research Article
ISSN: 1756-8692

Keywords

Content available
Book part
Publication date: 9 June 2022

Abstract

Details

Environmental Sustainability, Growth Trajectory and Gender: Contemporary Issues of Developing Economies
Type: Book
ISBN: 978-1-80262-154-9

Open Access
Article
Publication date: 12 June 2017

Gonzalo E. Sánchez

This paper aims to examine the short-term effect of the Arizona Immigration Law of 2010 (SB 1070) on the noncitizen Hispanic state population.

1181

Abstract

Purpose

This paper aims to examine the short-term effect of the Arizona Immigration Law of 2010 (SB 1070) on the noncitizen Hispanic state population.

Design/methodology/approach

To get a consistent estimate of this effect, a synthetic control method has been used to calculate a suitable counterfactual.

Findings

Results indicate that this bill produced a statistically significant short-term reduction in the proportion of noncitizen Hispanics in Arizona between 10 and 15 per cent. However, the evidence suggests that this effect vanishes after a few months.

Originality/value

These findings are consistent with previous evidence of the high mobility of the undocumented population in the US, and contribute to the understanding of the effects of federal and state-level immigration legislation.

Propósito

Este artículo examina el efecto a corto plazo de la Ley de Inmigración de Arizona de 2010 (SB 1070) sobre la población hispana no ciudadana.

Diseño/metodología/enfoque

Para obtener una estimación consistente sobre este efecto, he utilizado un método de control sintético para calcular una hipótesis de contraste adecuada.

Hallazgos

Los resultados indican que este proyecto produjo una reducción a corto plazo estadísticamente significativa en la proporción de hispanos no ciudadanos en Arizona —entre el 10% y el 15%—. Sin embargo, la evidencia sugiere que este efecto desaparece después de unos meses.

Originalidad/valor

Estos hallazgos son consistentes con la evidencia previa de la alta movilidad de la población indocumentada en los Estados Unidos, y contribuyen a la comprensión de los efectos de la legislación de inmigración federal y estatal.

Palabras clave

Población hispana, Inmigración ilegal, Control sintético

Tipo de artículo

Artículo de investigación

Details

Journal of Economics, Finance and Administrative Science, vol. 22 no. 42
Type: Research Article
ISSN: 2077-1886

Keywords

Content available
Article
Publication date: 1 December 2003

Marvin Rozner Jr

127

Abstract

Details

Aircraft Engineering and Aerospace Technology, vol. 75 no. 6
Type: Research Article
ISSN: 0002-2667

Keywords

Open Access
Article
Publication date: 28 July 2020

Ge Yang and Shutian Cen

Over the past 20 years, China's infrastructure has developed at an extraordinary speed. The current literature mainly focuses on the effects of political incentives on the…

Abstract

Purpose

Over the past 20 years, China's infrastructure has developed at an extraordinary speed. The current literature mainly focuses on the effects of political incentives on the infrastructure. However, this paper indicates that the structural change of China's land regime is an important clue and that the supernormal development of China's infrastructure is an explicable result for that.

Design/methodology/approach

This paper theoretically proves that in a politically centralized and economically decentralized economic entity with a public land-ownership regime, the self-financing mechanism formed by local officials through regulation of the land-grant price is the primary factor that influences the optimal supply volume of infrastructure in a region, in addition to political and economic incentives, and whether the self-financing mechanism can be formed or not depends on the structure of a country's land regime, which can help to explain the difference between the development of infrastructure in China and that in other developing countries from a theoretical angle.

Findings

The paper suggests that the mode is facing an important transformation toward land reform and new-type urbanization construction, and the replication and promotion of China's experience in infrastructure construction are of further significance under the Belt and Road Initiative as it provides a method for helping developing countries to eliminate infrastructure bottlenecks.

Originality/value

Through the test of multinational panel data, the paper indicates that the structural change of China's land regime around 1990 had an overall effect on the supernormal development of infrastructure in China. The paper indicates that the “land-based development mode” of China's infrastructure indeed contributed to the supernormal development of infrastructure in China, but there are still some shortcomings in this mode.

Details

China Political Economy, vol. 3 no. 1
Type: Research Article
ISSN: 2516-1652

Keywords

Open Access
Article
Publication date: 19 December 2023

Marcin Nowak, Marta Pawłowska-Nowak, Małgorzata Kokocińska and Piotr Kułyk

With the use of the grey incidence analysis (GIA), indicators such as the absolute degree of grey incidence (εij), relative degree of grey incidence (rij) or synthetic degree of…

214

Abstract

Purpose

With the use of the grey incidence analysis (GIA), indicators such as the absolute degree of grey incidence (εij), relative degree of grey incidence (rij) or synthetic degree of grey incidence (ρij) are calculated. However, it seems that some assumptions made to calculate them are arguable, which may also have a material impact on the reliability of test results. In this paper, the authors analyse one of the indicators of the GIA, namely the relative degree of grey incidence. The aim of the article was to verify the hypothesis: in determining the relative degree of grey incidence, the method of standardisation of elements in a series significantly affects the test results.

Design/methodology/approach

To achieve the purpose of the article, the authors used the numerical simulation method and the logical analysis method (in order to draw conclusions from our tests).

Findings

It turned out that the applied method of standardising elements in series when calculating the relative degree of grey incidence significantly affects the test results. Moreover, the manner of standardisation used in the original method (which involves dividing all elements by the first element) is not the best. Much more reliable results are obtained by a standardisation that involves dividing all elements by their arithmetic mean.

Research limitations/implications

Limitations of the conducted evaluation involve in particular the limited scope of inference. This is since the obtained results referred to only one of the indicators classified into the GIA.

Originality/value

In this article, the authors have evaluated the model of GIA in which the relative degree of grey incidence is determined. As a result of the research, the authors have proposed a recommendation regarding a change in the method of standardising variables, which will contribute to obtaining more reliable results in relational tests using the grey system theory.

Details

Grey Systems: Theory and Application, vol. 14 no. 2
Type: Research Article
ISSN: 2043-9377

Keywords

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