Philip Mark Hackney and Richard Wooldridge
Metal casting industry is in recovery phase after the crisis in 2008; customer demand continues to increase, with 98.6 million metric tons cast in 2011. Traditional ferrous and…
Abstract
Purpose
Metal casting industry is in recovery phase after the crisis in 2008; customer demand continues to increase, with 98.6 million metric tons cast in 2011. Traditional ferrous and non-ferrous casting techniques require one shot or permanent moulds which require tooling to produce. Tooling particularly for developmental projects can be costly and take valuable time to produce. Additive manufacturing (AM) has been used to manufacture sand patterns for metal sand casting using laser sintering and sand bonding. This research aims to focus on characterising the sand-bonded process developed by ExOne GmbhH Germany.
Design/methodology/approach
The approach taken in this research is to evaluate characteristics of parts built in the build volume for dimensional accuracy, tensile and compressive crush strength, density, impact strength and high temperature resistance. These properties are required to compare the 3D sand printing (3DSP) process to direct laser sand sintering (DLSS) and traditional Furan-based casting sand mixtures. The samples were taken from a production machine over a period of 30 days to ensure consistency.
Findings
The 3DSP process has the capability to manufacture sand patterns to an accuracy of ±0.5 mm or error less than 0.3 per cent; it has also demonstrated the best build position to achieve accurate parts. The research has demonstrated the 3DSP patterns are comparable to traditional methods for important casting material characteristics such as tensile, compression and impact strength. It has been shown that the 3DSP process is capable manufacturing significantly larger parts, with build production rates up to 30 times higher compared to similar parts manufactured via the DLSS process.
Research limitations/implications
As they has been very few 3DSP machines sold in Europe and particular UK, they has been little research into this new technique, and, therefore, they is a reliance on machine manufactures data for assessment. This research into 3DSP has increased the knowledge of this process significantly.
Practical implications
This research would be of interest to designers and manufacturing engineers wishing to take advantage of the implications of having new design freedom, tool less manufacturing with short lead times in a wide range of materials using fundamentally tried and tested century’s old casting techniques.
Originality/value
The research for this paper revealed very little published academic research in this area; therefore, this work will increase the body of knowledge for this niche AM process.
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Roman Liesenfeld, Jean-François Richard and Jan Vogler
We propose a generic algorithm for numerically accurate likelihood evaluation of a broad class of spatial models characterized by a high-dimensional latent Gaussian process and…
Abstract
We propose a generic algorithm for numerically accurate likelihood evaluation of a broad class of spatial models characterized by a high-dimensional latent Gaussian process and non-Gaussian response variables. The class of models under consideration includes specifications for discrete choices, event counts and limited-dependent variables (truncation, censoring, and sample selection) among others. Our algorithm relies upon a novel implementation of efficient importance sampling (EIS) specifically designed to exploit typical sparsity of high-dimensional spatial precision (or covariance) matrices. It is numerically very accurate and computationally feasible even for very high-dimensional latent processes. Thus, maximum likelihood (ML) estimation of high-dimensional non-Gaussian spatial models, hitherto considered to be computationally prohibitive, becomes feasible. We illustrate our approach with ML estimation of a spatial probit for US presidential voting decisions and spatial count data models (Poisson and Negbin) for firm location choices.
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Elizabeth H. Gorman and Fiona M. Kay
In elite professional firms, minorities are actively recruited but struggle to move upward. The authors argue that initiatives aimed at general skill development can have…
Abstract
In elite professional firms, minorities are actively recruited but struggle to move upward. The authors argue that initiatives aimed at general skill development can have unintended consequences for firm diversity. Specifically, the authors contend that approaches that win partner support through motivational significance and interpretive clarity provide a more effective avenue to skill development for minorities, who have less access than White peers to informal developmental opportunities. The authors also argue that a longer “partnership track,” which imposes a time limit on skill development, will benefit minority professionals. Using data on 601 offices of large US law firms in 1996 and 2005, the authors investigate the effects of five developmental initiatives and partnership track length on the representation of African-Americans, Latinxs, and Asian-Americans among partners. Observed effects are consistent with expectations, but patterns vary across racial-ethnic groups.
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Blue Wooldridge and Virginia Rose Cherry
A public library budget can serve varied purposes: a contract, a management tool, a communication mechanism, a financial control mechanism, a motivator, a plan, a major…
Abstract
A public library budget can serve varied purposes: a contract, a management tool, a communication mechanism, a financial control mechanism, a motivator, a plan, a major policy‐making tool and as an instrument of democracy. This paper presents a methodology that public library directors can use to determine if the budget contains the information they need in order to make decisions.
Michael D. Hausfeld, Gordon C. Rausser, Gareth J. Macartney, Michael P. Lehmann and Sathya S. Gosselin
In class action antitrust litigation, the standards for acceptable economic analysis at class certification have continued to evolve. The most recent event in this evolution is…
Abstract
In class action antitrust litigation, the standards for acceptable economic analysis at class certification have continued to evolve. The most recent event in this evolution is the United States Supreme Court’s decision in Comcast Corp. v. Behrend, 133 S. Ct. 1435 (2013). The evolution of pre-Comcast law on this topic is presented, the Comcast decision is thoroughly assessed, as are the standards for developing reliable economic analysis. This article explains how economic evidence of both antitrust liability and damages ought to be developed in light of the teachings of Comcast, and how liability evidence can be used by economists to support a finding of common impact for certification purposes. In addition, the article addresses how statistical techniques such as averaging, price-dispersion analysis, and multiple regressions have and should be employed to establish common proof of damages.
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Blue Wooldridge and H. Roland Weistroffer
Past research suggests that decision-making can be improved by gauging diverse view points from key stakeholders, where a stakeholder is any group or individual that can affect or…
Abstract
Past research suggests that decision-making can be improved by gauging diverse view points from key stakeholders, where a stakeholder is any group or individual that can affect or is affected by the decisions. Two key stakeholders in public policy making are economic experts that can predict the economic consequences of policy decisions, and elected policy-makers who are accountable to the citizens for the outcomes of these decisions. A two-step model combining a Decision Support System and a Delphi type approach is proposed. To test the methodology, the proposed approach was applied to revenue planning in a mid-sized city.
Richard Arhinful and Mehrshad Radmehr
The study seeks to find the effect of financial leverage on the firm performance of non-financial companies listed in the Tokyo stock market.
Abstract
Purpose
The study seeks to find the effect of financial leverage on the firm performance of non-financial companies listed in the Tokyo stock market.
Design/methodology/approach
The study collected data from 263 companies in the automobile and industrial producer sectors listed on the Tokyo stock exchange between 2001 and 2021. The generalized method of moments was used to estimate the effect of leverage on financial performance due to its ability to overcome the problems of endogeneity and autocorrelation.
Findings
The study found that the equity multiplier has a positive and statistically significant effect on return on assets (ROA), return on equity (ROE) and earning per share (EPS). The study discovered that the interest coverage ratio has a positive and statistically significant effect on ROA, ROE, EPS and Tobin’s Q. The results revealed that the degree of financial leverage and debt to earnings before interest, taxes, depreciation and amortization (EBITDA) have a negative and statistically significant effect on ROE, EPS and Tobin’s Q. The study also found that the capitalization ratios of the firms have a negative and statistically significant effect on ROA, ROE, EPS and Tobin’s Q.
Practical implications
The use of debt financing, which presents financial leverage, indicates that the companies can make enough earnings to pay off the interest and principal (debt service obligations), which were shown by the interest coverage ratio, as well as to pay all the long-term fixed expenses, which were shown by the fixed charge coverage ratio. Interest and fixed charge coverage have a positive statistically significant effect on the financial performance of automobile and industrial producer companies.
Originality/value
The study focused on the effect of financial leverage on financial performance by relying on pecking and trade-off theories to contribute to the existing body of literature in finance.
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R. Kelley Pace and James P. LeSage
We show how to quickly estimate spatial probit models for large data sets using maximum likelihood. Like Beron and Vijverberg (2004), we use the GHK (Geweke-Hajivassiliou-Keane…
Abstract
We show how to quickly estimate spatial probit models for large data sets using maximum likelihood. Like Beron and Vijverberg (2004), we use the GHK (Geweke-Hajivassiliou-Keane) algorithm to perform maximum simulated likelihood estimation. However, using the GHK for large sample sizes has been viewed as extremely difficult (Wang, Iglesias, & Wooldridge, 2013). Nonetheless, for sparse covariance and precision matrices often encountered in spatial settings, the GHK can be applied to very large sample sizes as its operation counts and memory requirements increase almost linearly with n when using sparse matrix techniques.
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In the last four years, since Volume I of this Bibliography first appeared, there has been an explosion of literature in all the main functional areas of business. This wealth of…
Abstract
In the last four years, since Volume I of this Bibliography first appeared, there has been an explosion of literature in all the main functional areas of business. This wealth of material poses problems for the researcher in management studies — and, of course, for the librarian: uncovering what has been written in any one area is not an easy task. This volume aims to help the librarian and the researcher overcome some of the immediate problems of identification of material. It is an annotated bibliography of management, drawing on the wide variety of literature produced by MCB University Press. Over the last four years, MCB University Press has produced an extensive range of books and serial publications covering most of the established and many of the developing areas of management. This volume, in conjunction with Volume I, provides a guide to all the material published so far.
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Yongseok Kim, Richard T. Gretz and Suman Basuroy
This paper examines the application of the latest iteration of the Uppsala model to digital products by empirically investigating the role of app updates in an app’s…
Abstract
Purpose
This paper examines the application of the latest iteration of the Uppsala model to digital products by empirically investigating the role of app updates in an app’s internationalization.
Design/methodology/approach
We align the evolution of apps through updates in a foreign market with the evolutionary process anchored in the latest Uppsala model and empirically test the model using our data of 410 non-Korean apps launched in South Korea. Particularly, we estimate the effect of app updates on an app’s foreign market performance. For the analysis, we employ a multiple fixed-effects regression model utilizing our panel data.
Findings
We present empirical support for the application of the latest Uppsala model to digital products in the context of apps and demonstrate a positive association between app evolution through updates and successful internationalization. We find that one additional app update is associated with a 6.2% increase in the number of monthly active users in the foreign market. We further show that this effect is conditional on time since entry and cultural distance.
Originality/value
This paper is the first to empirically test the latest Uppsala model in a digital context. Specifically, our work contributes to the emerging literature studying the impact of digitization on internationalization. We also provide empirical evidence supporting the strategic use of app updates to facilitate internationalization.