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Article

Vivekanand Venkataraman, Syed Usmanulla, Appaiah Sonnappa, Pratiksha Sadashiv, Suhaib Soofi Mohammed and Sundaresh S. Narayanan

The purpose of this paper is to identify significant factors of environmental variables and pollutants that have an effect on PM2.5 through wavelet and regression analysis.

Abstract

Purpose

The purpose of this paper is to identify significant factors of environmental variables and pollutants that have an effect on PM2.5 through wavelet and regression analysis.

Design/methodology/approach

In order to provide stable data set for regression analysis, multiresolution analysis using wavelets is conducted. For the sampled data, multicollinearity among the independent variables is removed by using principal component analysis and multiple linear regression analysis is conducted using PM2.5 as a dependent variable.

Findings

It is found that few pollutants such as NO2, NOx, SO2, benzene and environmental factors such as ambient temperature, solar radiation and wind direction affect PM2.5. The regression model developed has high R2 value of 91.9 percent, and the residues are stationary and not correlated indicating a sound model.

Research limitations/implications

The research provides a framework for extracting stationary data and other important features such as change points in mean and variance, using the sample data for regression analysis. The work needs to be extended across all areas in India and for various other stationary data sets there can be different factors affecting PM2.5.

Practical implications

Control measures such as control charts can be implemented for significant factors.

Social implications

Rules and regulations can be made more stringent on the factors.

Originality/value

The originality of this paper lies in the integration of wavelets with regression analysis for air pollution data.

Details

International Journal of Quality & Reliability Management, vol. 36 no. 10
Type: Research Article
ISSN: 0265-671X

Keywords

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Article

B.C. BROOKES

Haitun has recently shown that empirical distributions are of two types—‘Gaussian’ and ‘Zipfian’—characterized by the presence or absence of moments. Gaussian‐type…

Abstract

Haitun has recently shown that empirical distributions are of two types—‘Gaussian’ and ‘Zipfian’—characterized by the presence or absence of moments. Gaussian‐type distributions arise only in physical contexts: Zipfian only in social contexts. As the whole of modern statistical theory is based on Gaussian distributions, Haitun thus shows that its application to social statistics, including cognitive statistics, is ‘inadmissible’. A new statistical theory based on ‘Zipfian’ distributions is therefore needed for the social sciences. Laplace's notorious ‘law of succession’, which has evaded derivation by classical probability theory, is shown to be the ‘Zipfian’ frequency analogue of the Bradford law. It is argued that these two laws together provide the most convenient analytical instruments for the exploration of social science data. Some implications of these findings for the quantitative analysis of information systems are briefly discussed.

Details

Journal of Documentation, vol. 40 no. 2
Type: Research Article
ISSN: 0022-0418

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Article

Xiu Wei Yeap, Hooi Hooi Lean, Marius Galabe Sampid and Haslifah Mohamad Hasim

This paper investigates the dependence structure and market risk of the currency exchange rate portfolio from the Malaysian ringgit perspective.

Abstract

Purpose

This paper investigates the dependence structure and market risk of the currency exchange rate portfolio from the Malaysian ringgit perspective.

Design/methodology/approach

The marginal return of the five major exchange rates series, i.e. United States dollar (USD), Japanese yen (JPY), Singapore dollar (SGD), Thai baht (THB) and Chinese Yuan Renminbi (CNY) are modelled by the Bayesian generalized autoregressive conditional heteroskedasticity (GARCH) (1,1) model with Student's t innovations. In addition, five different copulas, such as Gumbel, Clayton, Frank, Gaussian and Student's t, are applied for modelling the joint distribution for examining the dependence structure of the five currencies. Moreover, the portfolio risk is measured by Value at Risk (VaR) that considers the extreme events through the extreme value theory (EVT).

Findings

The finding shows that Gumbel and Student's t are the best-fitted Archimedean and elliptical copulas, for the five currencies. The dependence structure is asymmetric and heavy tailed.

Research limitations/implications

The findings of this paper have important implications for diversification decision and hedging problems for investors who involving in foreign currencies. The authors found that the portfolio is diversified with the consideration of extreme events. Therefore, investors who are holding an individual currency with VaR higher than the portfolio may consider adding other currencies used in this paper for hedging.

Originality/value

This is the first paper estimating VaR of a currency exchange rate portfolio using a combination of Bayesian GARCH model, EVT and copula theory. Moreover, the VaR of the currency exchange rate portfolio can be used as a benchmark of the currency exchange market risk.

Details

International Journal of Emerging Markets, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1746-8809

Keywords

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Article

Eunhye (Olivia) Park, Bongsug Chae and Junehee Kwon

This paper aims to identify the intellectual structure of four leading hospitality journals over 40 years by applying mixed-method approach, using both machine learning…

Abstract

Purpose

This paper aims to identify the intellectual structure of four leading hospitality journals over 40 years by applying mixed-method approach, using both machine learning and traditional statistical analyses.

Design/methodology/approach

Abstracts from all 4,139 articles published in four top hospitality journals were analyzed using the structured topic modeling and inferential statistics. Topic correlation and community detection were applied to identify strengths of correlations and sub-groups of topics. Trend visualization and regression analysis were used to quantify the effects of the metadata (i.e. year of publication and journal) on topic proportions.

Findings

The authors found 50 topics and eight subgroups in the hospitality journals. Different evolutionary patterns in topic popularity were demonstrated, thereby providing the insights for popular research topics over time. The significant differences in topical proportions were found across the four leading hospitality journals, suggesting different foci in research topics in each journal.

Research limitations/implications

Combining machine learning techniques with traditional statistics demonstrated potential for discovering valuable insights from big text data in hospitality and tourism research contexts. The findings of this study may serve as a guide to understand the trends in the research field as well as the progress of specific areas or subfields.

Originality/value

It is the first attempt to apply topic modeling to academic publications and explore the effects of article metadata with the hospitality literature.

Details

International Journal of Contemporary Hospitality Management, vol. 30 no. 11
Type: Research Article
ISSN: 0959-6119

Keywords

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Article

Sawsan Halbouni

This study investigates the perceived suitability of the international accounting standards among the Jordanian preparers, users and auditors. Multivariate analysis and…

Abstract

This study investigates the perceived suitability of the international accounting standards among the Jordanian preparers, users and auditors. Multivariate analysis and non‐parametric statistics are applied to test hypotheses. The t‐test was used to measure the suitability of IAS to the Jordanian environment. The results indicated that IASC is a neutral body and therefore is capable of producing neutral and relevant accounting standards that might be applied by developing countries. The ANOVA and the Chisquare tests were applied to test variation in the perceived suitability of IAS to the Jordanian environment. The results indicated that the type of audit firm, years of experience and type of experience affected the respondents’ views towards the suitability of IAS to Jordan. Descriptive statistics were used to determine the most influential factor affecting the adoption of IAS in Jordan. The results indicated that the local need for foreign investments and international audit firms were the most influential factors while local and foreign investors in addition to the international audit firms are the biggest beneficiaries of that adoption. Finally, this study found that no attempt had been made by the Jordanian regulators to benefit from the past experience of other developing countries. The respondents believed that in order to increase the reliability of Jordanian financial information IAS were quickly adopted without any discussion as to whether each IAS was suitable to the Jordanian context.

Details

Journal of Economic and Administrative Sciences, vol. 21 no. 1
Type: Research Article
ISSN: 1026-4116

Keywords

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Book part

David E. Caughlin and Talya N. Bauer

Data visualizations in some form or another have served as decision-support tools for many centuries. In conjunction with advancements in information technology, data…

Abstract

Data visualizations in some form or another have served as decision-support tools for many centuries. In conjunction with advancements in information technology, data visualizations have become more accessible and more efficient to generate. In fact, virtually all enterprise resource planning and human resource (HR) information system vendors offer off-the-shelf data visualizations as part of decision-support dashboards as well as stand-alone images and displays for reporting. Plus, advances in programing languages and software such as Tableau, Microsoft Power BI, R, and Python have expanded the possibilities of fully customized graphics. Despite the proliferation of data visualization, relatively little is known about how to design data visualizations for displaying different types of HR data to different user groups, for different purposes, and with the overarching goal of improving the ways in which users comprehend and interpret data visualizations for decision-making purposes. To understand the state of science and practice as they relate to HR data visualizations and data visualizations in general, we review the literature on data visualizations across disciplines and offer an organizing framework that emphasizes the roles data visualization characteristics (e.g., display type, features), user characteristics (e.g., experience, individual differences), tasks, and objectives (e.g., compare values) play in user comprehension, interpretation, and decision-making. Finally, we close by proposing future directions for science and practice.

Details

Research in Personnel and Human Resources Management
Type: Book
ISBN: 978-1-78973-852-0

Keywords

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Article

Pedro Carlos Oprime, Fabiane Leticia Lizarelli, Marcio Lopes Pimenta and Jorge Alberto Achcar

The traditional Shewhart control chart, the X-bar and R/S chart, cannot give support to decide when it is not economically feasible to stop the process in order to remove…

Abstract

Purpose

The traditional Shewhart control chart, the X-bar and R/S chart, cannot give support to decide when it is not economically feasible to stop the process in order to remove special causes. Therefore, the purpose of this paper is to propose a new control chart design – a modified acceptance control chart, which provides a supportive method for decision making in economic terms, especially when the process has high capability indices.

Design/methodology/approach

The authors made a modeling expectation average run length (ARL), which incorporates the probability density function of the sampling distribution of Cpk, to compare and analyze the efficiency of the proposed design.

Findings

This study suggested a new procedure to calculate the control limits (CL) of the X-bar chart, which allows economic decisions about the process to be made. By introducing a permissible average variation and defining three regions for statistical CL in the traditional X-bar control chart, a new design is proposed.

Originality/value

A framework is presented to help practitioners in the use of the proposed control chart. Two new parameters (Cp and Cpk) in addition to m and n were introduced in the expected ARL equation. The Cpk is a random variable and its probability function is known. Therefore, by using a preliminary sample of a process under control, the authors can test whether the process is capable or not.

Details

International Journal of Quality & Reliability Management, vol. 36 no. 6
Type: Research Article
ISSN: 0265-671X

Keywords

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Article

Kaveh Hasani and Saman Sheikhesmaeili

– The purpose of this paper is to investigate the relationship between knowledge management (KM) and employee empowerment in institutions of higher education.

Abstract

Purpose

The purpose of this paper is to investigate the relationship between knowledge management (KM) and employee empowerment in institutions of higher education.

Design/methodology/approach

The research method in this study was the descriptive-correlative type, and was based on the goal of the method applied. Subjects in this research included the staff members of higher educational institutions in Iran. Descriptive and inferential statistics were used. To analyse research data, descriptive statistics, and for inferential statistics, the Pearson correlation, the Friedman ranking test and stepwise regression, were used. For data analysis, SPSS software was used.

Findings

The results from the study show that all alternative hypotheses were confirmed and there was a significant relationship between KM and employee empowerment. In addition, KM predicted the aspects of employee empowerment in institutions of higher education.

Originality/value

Through this study, the positive role of KM in employee empowerment in institutions of higher education has been described, and the importance of considering such studies has been specified for researchers.

Details

Kybernetes, vol. 45 no. 2
Type: Research Article
ISSN: 0368-492X

Keywords

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Article

Hamidreza Izadbakhsh, Rassoul Noorossana and Seyed Taghi Akhavan Niaki

The purpose of this paper is to apply Poisson generalized linear model (PGLM) with log link instead of multinomial logistic regression to monitor multinomial logistic…

Abstract

Purpose

The purpose of this paper is to apply Poisson generalized linear model (PGLM) with log link instead of multinomial logistic regression to monitor multinomial logistic profiles in Phase I. Hence, estimating the coefficients becomes easier and more accurate.

Design/methodology/approach

Simulation technique is used to assess the performance of the proposed algorithm using four different control charts for monitoring.

Findings

The proposed algorithm is faster and more accurate than the previous algorithms. Simulation results also indicate that the likelihood ratio test method is able to detect out-of-control parameters more efficiently.

Originality/value

The PGLM with log link has not been used to monitor multinomial profiles in Phase I.

Details

International Journal of Quality & Reliability Management, vol. 35 no. 3
Type: Research Article
ISSN: 0265-671X

Keywords

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Article

Saeed Sadeghi Boroujerdi, Kaveh Hasani and Vahid Delshab

This study aims to investigate the relationship between knowledge management (KM) and organizational innovation (OI) in higher educational institutions.

Abstract

Purpose

This study aims to investigate the relationship between knowledge management (KM) and organizational innovation (OI) in higher educational institutions.

Design/methodology/approach

The research method in the study was the descriptive – correlative type and was applied research based on the target. The study population consisted of managers and staff members of 63 Iranian higher educational institutions. In this research, descriptive and inferential statistics were used. To analyse research data, descriptive statistics, and for inferential statistics, the Pearson correlation coefficient test, the simple linear regression test and multiple regression tests were used. For data analysis, SPSS software was used.

Findings

The results of the study demonstrated that there was a significant relationship between KM and OI, and all alternative hypotheses were confirmed. In addition, KM predicted the aspects of organizational innovation in higher educational institutions.

Originality/value

This study supported the members of higher educational institutions to understand how to increase OIbetter and to improve the knowledge and experience of the employees through KM.

Details

Kybernetes, vol. 49 no. 2
Type: Research Article
ISSN: 0368-492X

Keywords

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