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1 – 10 of over 71000Larry J Williams, Mark B Gavin and Nathan S Hartman
The objective of this chapter is to provide strategy researchers with a general resource for applying structural equation modeling (SEM) in their research. This objective is…
Abstract
The objective of this chapter is to provide strategy researchers with a general resource for applying structural equation modeling (SEM) in their research. This objective is important for strategy researchers because of their increased use of SEM, the availability of advanced SEM approaches relevant for their substantive interests, and the fact that important technical work on SEM techniques often appear in outlets that may not be not readily accessible. This chapter begins with a presentation of the basics of SEM techniques, followed by a review of recent applications of SEM in strategic management research. We next provide an overview of five types of advanced applications of structural equation modeling and describe how they can be applied to strategic management topics. In a fourth section we discuss technical developments related to model evaluation, mediation, and data requirements. Finally, a summary of recommendations for strategic management researchers using SEM is also provided.
Yangtian Li, Haibin Li and Guangmei Wei
To present the models with many model parameters by polynomial chaos expansion (PCE), and improve the accuracy, this paper aims to present dimension-adaptive algorithm-based PCE…
Abstract
Purpose
To present the models with many model parameters by polynomial chaos expansion (PCE), and improve the accuracy, this paper aims to present dimension-adaptive algorithm-based PCE technique and verify the feasibility of the proposed method through taking solid rocket motor ignition under low temperature as an example.
Design/methodology/approach
The main approaches of this work are as follows: presenting a two-step dimension-adaptive algorithm; through computing the PCE coefficients using dimension-adaptive algorithm, improving the accuracy of PCE surrogate model obtained; and applying the proposed method to uncertainty quantification (UQ) of solid rocket motor ignition under low temperature to verify the feasibility of the proposed method.
Findings
The result indicates that by means of comparing with some conventional non-invasive method, the proposed method is able to raise the computational accuracy significantly on condition of meeting the efficiency requirement.
Originality/value
This paper proposes an approach in which the optimal non-uniform grid that can avoid the issue of overfitting or underfitting is obtained.
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Christofer R Edling and Fredrik Liljeros
We develop a model to analyze the growth of social organizations as a spatially nested mixed-influence diffusion process. Drawing on gravity models and threshold models, we split…
Abstract
We develop a model to analyze the growth of social organizations as a spatially nested mixed-influence diffusion process. Drawing on gravity models and threshold models, we split the social system into social units and model the diffusion process as a system of differential equations. The diffusion of a new organizational form in a social unit is a function of an internal process within the unit and external processes in the surrounding units. The model is confronted with data on the growth of trade unions in Stockholm, Sweden, between 1890 and 1940.
Bent Helge Nystad and Magnus Rasmussen
The purpose of this paper is to predict the remaining useful life of a natural gas export compressor, in order to assist decision making of the next planned work order.
Abstract
Purpose
The purpose of this paper is to predict the remaining useful life of a natural gas export compressor, in order to assist decision making of the next planned work order.
Design/methodology/approach
Extraction and aggregation of information from rapid developing condition‐monitoring systems has given rise to the Technical Condition Index (TCI) methodology. The trends of aggregated TCIs at compressor level and historical work orders were used as the basis for remaining useful life estimation.
Findings
The model is merging several condition‐related measurements and quantifying belief in aging versus belief in condition monitoring. This is important information in, for example, maintenance policy selection, and for the choice of a remaining useful life approach.
Practical implications
The model requires historical failure data and well documented condition‐related measurements. Investigation of the physics of failure at the component level also seems important for prognostic theory development.
Originality/value
The proposed methodology combines the TCI methodology, the survival analysis (PHM) methodology, and the general maximum‐likelihood theory to estimate and validate parameters and remaining useful life.
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Ahmed Eslam Salman and Magdy Raouf Roman
The study proposed a human–robot interaction (HRI) framework to enable operators to communicate remotely with robots in a simple and intuitive way. The study focused on the…
Abstract
Purpose
The study proposed a human–robot interaction (HRI) framework to enable operators to communicate remotely with robots in a simple and intuitive way. The study focused on the situation when operators with no programming skills have to accomplish teleoperated tasks dealing with randomly localized different-sized objects in an unstructured environment. The purpose of this study is to reduce stress on operators, increase accuracy and reduce the time of task accomplishment. The special application of the proposed system is in the radioactive isotope production factories. The following approach combined the reactivity of the operator’s direct control with the powerful tools of vision-based object classification and localization.
Design/methodology/approach
Perceptive real-time gesture control predicated on a Kinect sensor is formulated by information fusion between human intuitiveness and an augmented reality-based vision algorithm. Objects are localized using a developed feature-based vision algorithm, where the homography is estimated and Perspective-n-Point problem is solved. The 3D object position and orientation are stored in the robot end-effector memory for the last mission adjusting and waiting for a gesture control signal to autonomously pick/place an object. Object classification process is done using a one-shot Siamese neural network (NN) to train a proposed deep NN; other well-known models are also used in a comparison. The system was contextualized in one of the nuclear industry applications: radioactive isotope production and its validation were performed through a user study where 10 participants of different backgrounds are involved.
Findings
The system was contextualized in one of the nuclear industry applications: radioactive isotope production and its validation were performed through a user study where 10 participants of different backgrounds are involved. The results revealed the effectiveness of the proposed teleoperation system and demonstrate its potential for use by robotics non-experienced users to effectively accomplish remote robot tasks.
Social implications
The proposed system reduces risk and increases level of safety when applied in hazardous environment such as the nuclear one.
Originality/value
The contribution and uniqueness of the presented study are represented in the development of a well-integrated HRI system that can tackle the four aforementioned circumstances in an effective and user-friendly way. High operator–robot reactivity is kept by using the direct control method, while a lot of cognitive stress is removed using elective/flapped autonomous mode to manipulate randomly localized different configuration objects. This necessitates building an effective deep learning algorithm (in comparison to well-known methods) to recognize objects in different conditions: illumination levels, shadows and different postures.
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Luis Filipe Lages and David B. Montgomery
The article aims to test how pricing strategy adaptation to the foreign market mediates the relationship between export assistance and annual export performance improvement. It…
Abstract
Purpose
The article aims to test how pricing strategy adaptation to the foreign market mediates the relationship between export assistance and annual export performance improvement. It also aims to consider the effects of management international experience and export market competition.
Design/methodology/approach
Structural equation modelling with WLS estimation is used to test the direct and indirect influences of the variables on short‐term export performance.
Findings
Surprisingly, the findings reveal that the total effects of export assistance on annual export performance improvement are non‐significant, because although export assistance has a direct positive impact on performance, there is a negative indirect impact through export pricing strategy adaptation.
Research limitations/implications
These surprising results suggest that future research is required to incorporate and test the intervening and indirect effects among variables.
Practical implications
The findings also indicate that both export assistance and short‐term export performance improve with management international experience and export market competition.
Originality/value
Since both managers and public policy makers are often short‐term oriented, it is urgent to develop research to better understand determinants of short‐term performance as well as the antecedents of managerial and public policy resource allocation in the short term.
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Jinsheng Wang, Muhannad Aldosary, Song Cen and Chenfeng Li
Normal transformation is often required in structural reliability analysis to convert the non-normal random variables into independent standard normal variables. The existing…
Abstract
Purpose
Normal transformation is often required in structural reliability analysis to convert the non-normal random variables into independent standard normal variables. The existing normal transformation techniques, for example, Rosenblatt transformation and Nataf transformation, usually require the joint probability density function (PDF) and/or marginal PDFs of non-normal random variables. In practical problems, however, the joint PDF and marginal PDFs are often unknown due to the lack of data while the statistical information is much easier to be expressed in terms of statistical moments and correlation coefficients. This study aims to address this issue, by presenting an alternative normal transformation method that does not require PDFs of the input random variables.
Design/methodology/approach
The new approach, namely, the Hermite polynomial normal transformation, expresses the normal transformation function in terms of Hermite polynomials and it works with both uncorrelated and correlated random variables. Its application in structural reliability analysis using different methods is thoroughly investigated via a number of carefully designed comparison studies.
Findings
Comprehensive comparisons are conducted to examine the performance of the proposed Hermite polynomial normal transformation scheme. The results show that the presented approach has comparable accuracy to previous methods and can be obtained in closed-form. Moreover, the new scheme only requires the first four statistical moments and/or the correlation coefficients between random variables, which greatly widen the applicability of normal transformations in practical problems.
Originality/value
This study interprets the classical polynomial normal transformation method in terms of Hermite polynomials, namely, Hermite polynomial normal transformation, to convert uncorrelated/correlated random variables into standard normal random variables. The new scheme only requires the first four statistical moments to operate, making it particularly suitable for problems that are constraint by limited data. Besides, the extension to correlated cases can easily be achieved with the introducing of the Hermite polynomials. Compared to existing methods, the new scheme is cheap to compute and delivers comparable accuracy.
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Choice under risk has a large stochastic (unpredictable) component. This chapter examines five stochastic models for binary discrete choice under risk and how they combine with…
Abstract
Choice under risk has a large stochastic (unpredictable) component. This chapter examines five stochastic models for binary discrete choice under risk and how they combine with “structural” theories of choice under risk. Stochastic models are substantive theoretical hypotheses that are frequently testable in and of themselves, and also identifying restrictions for hypothesis tests, estimation and prediction. Econometric comparisons suggest that for the purpose of prediction (as opposed to explanation), choices of stochastic models may be far more consequential than choices of structures such as expected utility or rank-dependent utility.
Constructing and evaluating behavioral science models is a complex process. Decisions must be made about which variables to include, which variables are related to each other, the…
Abstract
Constructing and evaluating behavioral science models is a complex process. Decisions must be made about which variables to include, which variables are related to each other, the functional forms of the relationships, and so on. The last 10 years have seen a substantial extension of the range of statistical tools available for use in the construction process. The progress in tool development has been accompanied by the publication of handbooks that introduce the methods in general terms (Arminger et al., 1995; Tinsley & Brown, 2000a). Each chapter in these handbooks cites a wide range of books and articles on specific analysis topics.