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991.
Supersaturated designs (SSDs) constitute an important class of fractional factorial designs that could be extremely useful in factor screening experiments. Most of the existing studies have focused on balanced designs. This paper provides a new lower bound for the \(E(f_{NOD})\)-optimality measure of SSDs with general run sizes. This bound is a generalization of existing bounds since it is applicable to both balanced and unbalanced designs. Optimal multi and mixed-level, balanced and nearly balanced SSDs are constructed by applying a k-circulant type methodology. Necessary and sufficient conditions are introduced for the generator vectors, in order to pre-ensure the optimality of the constructed k-circulant SSDs. The provided lower bounds were used to measure the efficiency of the generated designs. The presented methodology leads to a number of new families of improved SSDs, providing tools for directly constructing optimal or nearly-optimal k-circulant designs by just checking the corresponding generator vector.  相似文献   
992.
A framework for the detection of change points in the expectation in sequences of random variables is presented. Specifically, we investigate time series with general distributional assumptions that may show an unknown number of change points in the expectation occurring on multiple time scales and that may also contain change points in other parameters. To that end we propose a multiple filter test (MFT) that tests the null hypothesis of constant expectation and, in case of rejection of the null hypothesis, an algorithm that estimates the change points.The MFT has three important benefits. First, it allows for general distributional assumptions in the underlying model, assuming piecewise sequences of i.i.d. random variables, where also relaxations with regard to identical distribution or independence are possible. Second, it uses a MOSUM type statistic and an asymptotic setting in which the MOSUM process converges weakly to a functional of a Brownian motion which is then used to simulate the rejection threshold of the statistical test. This approach enables a simultaneous application of multiple MOSUM processes which improves the detection of change points that occur on different time scales. Third, we also show that the method is practically robust against changes in other distributional parameters such as the variance or higher order moments which might occur with or even without a change in expectation. A function implementing the described test and change point estimation is available in the R package MFT.  相似文献   
993.
Strategic flexibility is a vital capability for new ventures to update their strategies in a timely manner. However, the role of external knowledge sources in new ventures’ endeavours to develop strategic flexibility are unclear. Drawing on the knowledge‐based and relational views, we explore the effect of two sources of external knowledge: new product development (NPD) alliances, representing tightly coupled sources, and loosely coupled sources such as industry associations. Our field study of 148 high‐tech ventures found that the extent to which firms utilize knowledge from NPD alliances has a curvilinear relationship with strategic flexibility, whereas the extent to which firms utilize loosely coupled sources has a positive linear relationship with strategic flexibility. We also found that in new ventures, decentralization of decision‐making and institutional support enhance knowledge integration, positively moderating these relationships.  相似文献   
994.
This paper develops a real options decision support tool for raising the performance of the firm. It shows how entrepreneurs can use our intuitive tool quickly to assess the nature and type of action required for improved performance. This exploits our estimated econometric relationship between precipitators of entrepreneurial opportunities, time until exercise, and firm performance. Our 3D chromaticity plots show how staging investments, investment time, and firm performance support entrepreneurial decisions to embed, or to expedite, investments. Speedy entrepreneurial action is securely supported with this tool, without expertise in econometric estimation or in formulae for real options valuation.  相似文献   
995.
This paper examines determinants of process innovation introductions across 115 (mostly) developing countries. Empirical research on process innovations lags behind product innovations. Accounting for firm characteristics, R&D, regulations and taxes, and corruption, results show that sole proprietors and R&D‐performing firms were more likely to introduce innovations, whereas greater prosperity made them less likely to do so. Corruption had a greasing effect, whereas firms in island nations were less likely to introduce, ceteris paribus. Effects of regulations and taxes and other firm characteristics were largely insignificant. Finally, some differences existed across manufacturing and service industries and across prevalence of innovation introductions.  相似文献   
996.
Recent decades have seen a fundamental shift in the nature of economic regulation in the United States. Unauthorized by congress, and largely unnoted in legal and academic circles, regulatory agencies such as the Federal Communications Commission have changed the regulatory process by linking otherwise unrelated regulatory issues. Examples include tying merger approval to firm commitments to engage in conceptually unrelated build‐outs and other projects of political importance. This linking of issues has several effects, the most prominent being (a) tying regulatory issues changes the outcomes obtained, plausibly in predictable ways; (b) tying in some circumstances allows regulators to extend their authority to issues for which they have little or no legal authority; and (c) tied regulatory bargaining fails to produce valid legal precedent for firm decision making. We provide an analysis of these conclusions by examining the increasing use of consent decrees, voluntary merger commitments, and merger conditions by the Federal Communications Commission, referencing our discussion with a simple model of joint bargaining applicable to regulatory practice.  相似文献   
997.
Two key groups central to improving firm performance are the top management team (TMT) and the board of directors. Executives undertake strategic actions, whereas board members fulfill their resource provision and monitoring roles. Drawing on tournament theory and equity theory, we propose that high pay dispersion among outside directors and the TMT is positively associated with strategic risk, whereas high (low) TMT pay dispersion and low (high) outside director pay dispersion are positively associated with firm performance. Our predictor is the unexplained component of horizontal pay dispersion, or the residual of pay dispersion resulting from regressing pay on observable firm, industry, period, and individual characteristics. Our results highlight the importance of unexplained pay dispersion for TMTs, but not for boards of directors, in improving firm performance.  相似文献   
998.
This study explores how supervisor career mentoring contributes to contemporary organizational career development, which strives to foster employees' promotability while strengthening their intention to stay. Specifically, we focus on the implications of career mentoring in team contexts. Applying a multilevel framework, we distinguish between individual‐level differentiated mentoring (i.e., an employee's mentoring perceptions as compared to those of other team members) and group‐level career mentoring climate (i.e., the average perception across all group members). In a workplace setting, we collected data from vocational job starters (N ranged from 230 to 290) and their company supervisors (N ranged from 56 to 68). We find that career mentoring climate positively relates to promotability, more so than differentiated career mentoring. Both career mentoring climate and differentiated career mentoring are positively related to the intention to stay. At the individual level, this relationship is mediated by job satisfaction. We discuss theoretical and practical implications of differentiated and group‐level mentoring.  相似文献   
999.
1000.
Organizations increasingly depend on employee efforts to innovate. However, the quality of relationships between leaders and employees may affect the recognition that employees receive for their innovative work behaviors. Drawing from a social cognition perspective, we tested a model in which leader–member exchange (LMX) moderates the impact of employee innovative work behavior on supervisory ratings of employee performance. Results from two multisource studies combining self, colleague, and supervisor ratings consistently showed that employees receive more favorable performance ratings by engaging in innovative work behavior when they have high‐quality LMX relationships. Moreover, we found that this interactive relationship was mediated by leader perceptions of innovative employee efforts, providing support for a moderated mediation model. Implications for the literatures on performance appraisal, LMX, and innovation are discussed.  相似文献   
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