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Book part
Publication date: 18 October 2019

Jianghao Chu, Tae-Hwy Lee and Aman Ullah

In this chapter we consider the “Regularization of Derivative Expectation Operator” (Rodeo) of Lafferty and Wasserman (2008) and propose a modified Rodeo algorithm for…

Abstract

In this chapter we consider the “Regularization of Derivative Expectation Operator” (Rodeo) of Lafferty and Wasserman (2008) and propose a modified Rodeo algorithm for semiparametric single index models (SIMs) in big data environment with many regressors. The method assumes sparsity that many of the regressors are irrelevant. It uses a greedy algorithm, in that, to estimate the semiparametric SIM of Ichimura (1993), all coefficients of the regressors are initially set to start from near zero, then we test iteratively if the derivative of the regression function estimator with respect to each coefficient is significantly different from zero. The basic idea of the modified Rodeo algorithm for SIM (to be called SIM-Rodeo) is to view the local bandwidth selection as a variable selection scheme which amplifies the coefficients for relevant variables while keeping the coefficients of irrelevant variables relatively small or at the initial starting values near zero. For sparse semiparametric SIM, the SIM-Rodeo algorithm is shown to attain consistency in variable selection. In addition, the algorithm is fast to finish the greedy steps. We compare SIM-Rodeo with SIM-Lasso method in Zeng et al. (2012). Our simulation results demonstrate that the proposed SIM-Rodeo method is consistent for variable selection and show that it has smaller integrated mean squared errors (IMSE) than SIM-Lasso.

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Topics in Identification, Limited Dependent Variables, Partial Observability, Experimentation, and Flexible Modeling: Part B
Type: Book
ISBN: 978-1-83867-419-9

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Article
Publication date: 10 January 2023

Qunsheng Wang, Bin Zhu, Fubin Zhang, Xuesong Jiang and Jie Wang

While the normal wheel–rail contact model cannot be accurately used for light rail transit (LRT) wheel wear analysis with large wheelset lateral displacement and wheelset yaw…

92

Abstract

Purpose

While the normal wheel–rail contact model cannot be accurately used for light rail transit (LRT) wheel wear analysis with large wheelset lateral displacement and wheelset yaw angle, a modified semi-Hertzian contact model (MSHM) is proposed in the paper.

Design/methodology/approach

MSHM was first proposed to consider the wheelset motion with the lateral displacement and the yaw angle. Then, a dynamic model of an LRT was established and the influence of some key factors on wheel wear is analyzed. At last, after operating for a certain mileage, the predicted wheel wear is compared with the tested wheel wear.

Findings

Compared with the tested wheel wear, the predicted wheel wear shows a good agreement with the measured result, verifying the accuracy of MSHM.

Originality/value

Considering larger wheelset lateral displacement and yaw angle, MSHM can be used to calculate the wheel wear of the LRT with high accuracy.

Details

Industrial Lubrication and Tribology, vol. 75 no. 2
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 2 October 2009

Zhu Zeng

The purpose of this paper is to examine the relationship between patent innovation activities and foreign trade competitiveness and analyze China's level of independent knowledge…

954

Abstract

Purpose

The purpose of this paper is to examine the relationship between patent innovation activities and foreign trade competitiveness and analyze China's level of independent knowledge innovation internationally, especially in comparison with Japan.

Design/methodology/approach

The approach takes the form of a statistical and econometric analysis of granted patents and trade export effect of China and Japan, based on the monthly data of foreign trade import and export and of patents granted by China's national intellectual property bureau in Japan and China, respectively, from 2004 to 2007.

Findings

Through Johansen's co‐integration test, Granger causality test and other methods, this paper verifies that a country's inventions can directly promote export trade, and its pulling effect is more visible than the total patents. Tests also manifest that the innovative activities in Japan play a more significant role in enhancing its exports than in China. Comparison of large amounts of data shows that the gap between China and Japan on independent knowledge innovation is obvious.

Research limitations/implications

These imply that in the era of knowledge economy, a country's sustainable capacity for independent innovation is the key to trade and national competitiveness.

Practical implications

China urgently needs to build a national innovation system; make great efforts to cultivate national competitive advantage centred on knowledge advantage; and improve its overall competitive strength.

Originality/value

The paper assesses the importance of innovation activities represented by patents from the quantitative view and the difference of impact degree between China and Japan.

Details

Journal of Chinese Economic and Foreign Trade Studies, vol. 2 no. 3
Type: Research Article
ISSN: 1754-4408

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Article
Publication date: 6 December 2024

Yun Shen, Damien Wallace, Vikash Ramiah and Krishna Reddy

This study examines the influence of CEO characteristics on firm innovation within the Australian market, using R&D expenditure as a proxy for innovation. The aim is to analyze…

86

Abstract

Purpose

This study examines the influence of CEO characteristics on firm innovation within the Australian market, using R&D expenditure as a proxy for innovation. The aim is to analyze how factors such as CEO gender, educational background and dual roles (CEO-chairman) impact firms' R&D investment across various industries.

Design/methodology/approach

Panel and Tobit regression models are employed to assess the relationship between CEO characteristics and R&D expenditure. The study controls for endogeneity and applies firm-level control variables to ensure robustness, examining CEO traits like gender, educational qualifications and CEO-chairman duality.

Findings

The study reveals that CEO gender and educational level significantly impact firm innovation, particularly R&D expenditure, compared to other characteristics like CEO-chairman duality. Female CEOs and those with PhD degrees are associated with higher R&D spending, with variations across industries such as basic materials and healthcare.

Research limitations/implications

The study is limited by its focus on Australian firms and the time span of 2006–2016. Additionally, mixed results for CEO-chairman duality and CEO location may reduce the generalizability of the findings across all industries on the ASX.

Practical implications

The findings highlight the importance of gender diversity and CEO education in driving firm innovation. Companies aiming to enhance competitiveness and performance through R&D activities, especially in industry-specific contexts, should consider these CEO characteristics.

Originality/value

This study provides novel insights by analyzing the impact of CEO characteristics, such as gender and education level, on firm innovation in the underexplored Australian market. By using R&D expenditure as a proxy for innovation and employing both panel and Tobit regression models, it highlights the significance of CEO traits, particularly in specific industries. The findings emphasize the stronger influence of CEO gender and educational level compared to CEO-chairman duality and location, offering valuable implications for gender diversity and industry-specific innovation strategies in enhancing firm competitiveness.

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Journal of Accounting Literature, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0737-4607

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Article
Publication date: 26 January 2022

Xingyu Ken Chen, Jin-Cheon Na, Luke Kien-Weng Tan, Mark Chong and Murphy Choy

The COVID-19 pandemic has spurred a concurrent outbreak of false information online. Debunking false information about a health crisis is critical as misinformation can trigger…

410

Abstract

Purpose

The COVID-19 pandemic has spurred a concurrent outbreak of false information online. Debunking false information about a health crisis is critical as misinformation can trigger protests or panic, which necessitates a better understanding of it. This exploratory study examined the effects of debunking messages on a COVID-19-related public chat on WhatsApp in Singapore.

Design/methodology/approach

To understand the effects of debunking messages about COVID-19 on WhatsApp conversations, the following was studied. The relationship between source credibility (i.e. characteristics of a communicator that affect the receiver's acceptance of the message) of different debunking message types and their effects on the length of the conversation, sentiments towards various aspects of a crisis, and the information distortions in a message thread were studied. Deep learning techniques, knowledge graphs (KG), and content analyses were used to perform aspect-based sentiment analysis (ABSA) of the messages and measure information distortion.

Findings

Debunking messages with higher source credibility (e.g. providing evidence from authoritative sources like health authorities) help close a discussion thread earlier. Shifts in sentiments towards some aspects of the crisis highlight the value of ABSA in monitoring the effectiveness of debunking messages. Finally, debunking messages with lower source credibility (e.g. stating that the information is false without any substantiation) are likely to increase information distortion in conversation threads.

Originality/value

The study supports the importance of source credibility in debunking and an ABSA approach in analysing the effect of debunking messages during a health crisis, which have practical value for public agencies during a health crisis. Studying differences in the source credibility of debunking messages on WhatsApp is a novel shift from the existing approaches. Additionally, a novel approach to measuring information distortion using KGs was used to shed insights on how debunking can reduce information distortions.

Details

Online Information Review, vol. 46 no. 6
Type: Research Article
ISSN: 1468-4527

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Article
Publication date: 7 December 2015

Lifang Cui, Gillian Hubbard and Margaret Gleeson

The purpose of this paper is to survey and consider the implications of the literature justifying the value of teaching poetry. There has been a long tradition of literature…

1493

Abstract

Purpose

The purpose of this paper is to survey and consider the implications of the literature justifying the value of teaching poetry. There has been a long tradition of literature education in the English departments of Chinese universities. English Poetry courses are offered within optional literature modules in senior stages of a BA in English language and literature. In 2000, the new national syllabus for tertiary English majors was issued. This syllabus has brought the teaching of English into line with the perceived practical needs of society. As a result, poetry courses have been under threat within the degree. A substantial number of university teachers have responded to this threat with articles arguing the value of teaching of poetry.

Design/methodology/approach

The China National Knowledge Infrastructure (CNKI), the largest database of academic journals in China, reveals that from 2000 to 2013, 102 articles about teaching English poetry to Chinese people learning English as a foreign language were published in Chinese academic journals, of which 67 are concerned with English majors. This literature examines these 67 articles.

Findings

These articles justify the purpose of teaching English poetry, evaluate the content of poetry courses and share pedagogical strategies. The issues within this discussion fall into three categories: why teach poetry; what to teach in poetry courses; and how to teach poetry. Because the commitment of Chinese teachers to sharing their beliefs about teaching English poetry is positioned in the context of increased advocacy for the creation of inter-disciplinary market-orientated graduates, discomfort, uncertainty and the desire for change emerge in this discussion. On the other hand, teachers looking for change express caution about the costs of changing pedagogical approaches on the development of the skills of close reading and analysis of poetical texts.

Originality/value

This investigation of the local Chinese context resonates with and contributes to the wider discussion of the challenges faced by English literature teachers in both second- (L2) and first-language (L1) contexts and warrants examination. It is difficult to say in advance how far such knowledge could contribute to any policy decisions that may be made in the future, but it is important that the voice of teachers contributes to the larger international debate about the value of humanities in tertiary-level education.

Details

English Teaching: Practice & Critique, vol. 14 no. 3
Type: Research Article
ISSN: 1175-8708

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Available. Open Access. Open Access
Article
Publication date: 26 September 2024

Xihong Jin and Feng Guo

The principle of infinite life design currently directs fatigue resistance strategies for metro car bodies. However, this principle might not fully account for the dynamic…

161

Abstract

Purpose

The principle of infinite life design currently directs fatigue resistance strategies for metro car bodies. However, this principle might not fully account for the dynamic influence of operational loads and the inevitable presence of defects. This study aims to integrate methods of service life estimation and residual life assessment, which are based on operational loads, into the existing infinite life verification framework to further ensure the operational safety of subway trains.

Design/methodology/approach

Operational loads and fatigue loading spectra were determined through the field test. The material test was conducted to investigate characteristics of the fracture toughness and the crack growth rate. The fatigue strength of the metro car body was first verified using the finite element method and Moore–Kommers–Japer diagrams. The service life was then estimated by applying the Miner rule and high-cycle fatigue curves in a modified form of the Basquin equation. Finally, the residual life was assessed utilizing a fracture assessment diagram and a fitted curve of crack growth rate adhered to the Paris formula.

Findings

Neither the maximum utilization factor nor the cumulative damage exceeds the threshold value of 1.0, the metro car body could meet the design life requirement of 30 years or 6.6 million km. However, three out of five fatigue key points were significantly influenced by the operational loads, which indicates that a single fatigue strength verification cannot achieve the infinite life design objective of the metro car body. For a projected design life of 30 years, the tolerance depth is 12.2 mm, which can underscore a relatively robust damage tolerance capability.

Originality/value

The influence of operational loads on fatigue life was presented by the discrepancy analysis between fatigue strength verification results and service life estimation results. The fracture properties of butt-welded joints were tested and used for the damage tolerance assessment. The damage tolerance life can be effectively related by a newly developed equation in this study. It can be a valuable tool to provide the theoretical guidance and technical support for the structural improvements and maintenance decisions of the metro car body.

Details

Railway Sciences, vol. 3 no. 5
Type: Research Article
ISSN: 2755-0907

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Article
Publication date: 25 December 2023

Hazem Aldabbas and Amel Bettayeb

Although the study of factors that promote employee well-being is not a new research area, the impact of managerial caring and perceived insider status on subjective employee…

445

Abstract

Purpose

Although the study of factors that promote employee well-being is not a new research area, the impact of managerial caring and perceived insider status on subjective employee well-being is a relatively new and unexplored area within the management literature. Therefore, this study examined the relationship between managerial caring and subjective employee well-being while considering the mediating effect of perceived insider status. Based on social identity theory, the study hypothesized that perceived insider status mediates the link between managerial caring and subjective employee well-being.

Design/methodology/approach

The study analyzed data from 193 employees working across various industries in the United Arab Emirates using Process Macro Model 4.

Findings

The findings revealed a positive relationship between managerial caring and employee well-being, which was influenced by the mediating effect of perceived insider status.

Originality/value

The study’s results, which shed light on the process by which managerial caring positively affects employee well-being, provide valuable insights for developing a caring workplace. The findings make a significant contribution to the literature on managerial caring by explaining how the mediating role of perceived insider status influences the relationship between managerial caring and subjective employee well-being.

Details

International Journal of Workplace Health Management, vol. 17 no. 1
Type: Research Article
ISSN: 1753-8351

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Article
Publication date: 3 March 2022

Changpeng Chen, Zhongxu Xiao, Gang Xue, Hailong Liao and Haihong Zhu

High temperature gradient induces high residual stress, producing an important effect on the part manufacturing during laser powder bed fusion (LPBF). The purpose of this study is…

248

Abstract

Purpose

High temperature gradient induces high residual stress, producing an important effect on the part manufacturing during laser powder bed fusion (LPBF). The purpose of this study is to investigate the effect of the molten pool mode on the thermal stress of Ti-6Al-4V alloy during different deposition processes.

Design/methodology/approach

A coupled thermal-mechanical finite element model was built. The developed model was validated by comparing the numerical results with the experimental data in the maximum molten pool temperature, the molten pool dimension and the residual stress described in the previous work.

Findings

For the single-track process, the keyhole mode caused an increase in both the maximum stress and the high-stress area compared with the conduction mode. For the multitrack process, a lower tensile stress around the scanning track and a higher compressive stress below the scanning track were found in the keyhole mode. For the multilayer process, the stress along the scanning direction at the middle of the part changed from tensile stress to compressive stress with the increase in the deposition layer number. As the powder layer number increased, the stress along the scanning direction near the top surface of the part decreased while the stress along the deposition direction obviously increased, indicating that the stress along the deposition direction became the dominant stress. The keyhole mode can reduce the residual stress near the top of the part, and the conduction mode was more likely to produce a low residual stress near the bottom of the part.

Originality/value

The results provide a systematic understanding of thermal stress during the LPBF process.

Details

Rapid Prototyping Journal, vol. 28 no. 7
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 11 July 2024

Sattar Khan, Naimat Ullah Khan and Yasir Kamal

This paper aims to examine the role of corporate governance (CG) in the earnings management (EM) of affiliated companies in family business groups (FBGs) listed on the Pakistan…

194

Abstract

Purpose

This paper aims to examine the role of corporate governance (CG) in the earnings management (EM) of affiliated companies in family business groups (FBGs) listed on the Pakistan Stock Exchange (PSX), using principal–principal agency theory.

Design/methodology/approach

The sample of 327 nonfinancial firms of the PSX, consisting of 187 group-affiliated firms and 140 nonaffiliated firms has been used in this study for the period of 2010 to 2019. The study uses different regression models for analysis, with robustness tests of various alternative measures of EM and FBG affiliation. In addition, endogeneity is controlled with the propensity score matching method.

Findings

The findings show that EM is less prevalent in affiliated firms compared to nonaffiliated companies. The results show a negative and significant relationship between FBGs affiliated firms and EM. Moreover, the results also show a positive relationship between EM and the interaction term of the CG index and group affiliation. It refers to the fact that effective governance cannot reduce EM in affiliated companies of FBGs as well as in the nonfinancial companies of the PSX. In addition, the quality of CG is higher in affiliated companies compared to its counterpart in nonaffiliated firms. The findings support the principal–principal agency theory that CG cannot mitigate the expropriating behavior of controlling shareholders against minority shareholders by reducing EM in emerging markets due to the ownership concentration phenomenon.

Research limitations/implications

This research study has implications for small investors, government agencies and regulators. The findings of the study show that CG code should make it mandatory for companies to reveal information about their complex ownership structure and ownership information about affiliated companies and directors. Furthermore, it is suggested to revisit the code of CG in the Pakistani context of principal–principal conflict instead of the agent–principal explanation of agency theory based on Anglo–Saxon countries.

Originality/value

This research study has contributed to the CG and FBG literature in relation to EM in idiosyncratic settings of Pakistan. One of the prime contributions of the paper is the development of a comprehensive CG index. This research study used detailed, manually collected novel data on affiliated firms of FBGs in Pakistan.

Details

Corporate Governance: The International Journal of Business in Society, vol. 25 no. 2
Type: Research Article
ISSN: 1472-0701

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