When VAR models are used to predict future outcomes, the forecast error can be substantial. Through imposition of restrictions on the off-diagonal elements of the parameter matrix, however, the information in the process may be condensed to the marginal processes. In particular, if the cross-autocorrelations in the system are small and only a small sample is available, then such a restriction may reduce the forecast mean squared error considerably.
In this paper, we propose three different techniques to decide whether to use the restricted or unrestricted model, i.e. the full VAR(1) model or only marginal AR(1) models. In a Monte Carlo simulation study, all three proposed tests have been found to behave quite differently depending on the parameter setting. One of the proposed tests stands out, however, as the preferred one and is shown to outperform other estimators for a wide range of parameter settings. 相似文献
This article presents an alternative perspective regarding the concept of “propaganda” in the historiography of public relations. Recent scholars of public relations have rightly criticized early attempts to write the field’s history as a linear progression, from propaganda to excellence. At the same time, however, the same recent scholars have come to accept a linear conceptual change, and that “propaganda” became an impossible term in liberal democratic countries in the 1960s. By using the empirical case of the massive communication efforts initiated by the Swedish Commission on Right-Hand Traffic, which was assigned to implement right-hand traffic in 1967, this article shows that the concept of “propaganda” both occurred frequently and was used in a neutral sense. To deepen the understanding of this alternative perspective, the article both presents how the historical actors conceptualized their work, and describes how the communication work of the Commission was performed. 相似文献
This article examines how a social venture transitions from nascent to formal status and argues that the transformation of the organization set in motion by establishing formal boundaries is a deeply profound one. Drawing from the nonprofit and social entrepreneurship literature on what prompts and energizes individuals to initiate new not-for-profit ventures, and linking it to a notion of revolutionary crisis as organizations emerge and develop, we seek to illuminate and explore the tension, and its consequences, between nonprofit entrepreneurs and the organization they create as the new venture transitions from nascent to formal. We do this by presenting the results from an in-depth case study examining the gestation and boundary-forming phases of Robert’s Place Cooperative, a plucky start-up cooperative in a midsize Midwestern city. 相似文献
Increasingly many firms have started to implement programs intended to improve the workers' health and the psychosocial work‐environment, as well as other attributes of labor quality. Motivated by the need for evaluating to what extent the programs affect a firm's productivity performance, this study discusses a model for analyzing the contribution of labor quality attributes toward firm productivity. To assess the contribution from the labor quality attributes, we model firm productivity as the outcome of two separate processes within a firm: the physical production process and the labor quality process. Firm productivity is measured by a Malmquist‐like productivity index and is computed by Data Envelopment Analysis. Based on bootstrap methods we analyze potential statistical bias and provide bias‐corrected productivity estimates. The labor quality attributes are first modeled at an individual worker level as latent variables using Item Response Theory, and then aggregated to a firm‐level. The model is empirically validated using data from three manufacturing plants that participated in a coordinated worksite health promotion program. Over a 4‐year period (2000–2003), we observed a general improvement in efficiency of 2–5%, half of which could be attributed to an improvement in workers' health and psychosocial work‐environment. A key benefit with the model is that it is practical, easy to implement, and very fast to compute. The model also constructively contributes to the discourse on sustainability by providing a framework for deriving meaningful metrics and providing tangible measurements on the effect of sustainability‐related issues. 相似文献
The business model has become a popular concept in business and management fields. Yet, it is suffering from a paradox between outstanding popularity and severe criticism, which appears to impede the positive development of the scholarly discourse on the business model concept. Against this background, the purpose of this study is to provide insight into the antecedents of this paradox and to understand their implications for the future development of the concept. The following contributions are made. First, the authors apply a narrative approach to recognizing and interpreting the paradox, and introduce the analysis of syntactics of scholarly discourse as a novel method of investigating management concepts. Second, as a result of elaborating on recurrent themes and tensions in scholarly discourse, the authors extend the literature on business models through theorizing on the core of the concept along the dimensions of classification, constitution and configuration. In particular, they identify the simultaneity of separation and attachment as the main antecedent of the business model paradox. Third, the authors offer implications for further advancing the development of this management concept, and highlight the need for spurring integrative research while at the same time maintaining a plurality of perspectives. 相似文献
Using a contingent valuation survey, people's willingness to pay for a given risk reduction is found to be much larger, consistently more than two times as large, when traveling by air compared to by taxi. Follow-up questions revealed that an important reason for this discrepancy is that many experience a higher mental suffering from flying, and that they are willing to pay to reduce this suffering. It was also consistently found that people are willing to pay more for a certain risk reduction if the original price was higher. Policy implications are discussed. 相似文献
A common assertion in the nonprofit literature is that nonprofit organizations can become more efficient, effective, and sustainable by embracing social entrepreneurship in their operational and strategic posture. In this article, we examine whether the mere label of social entrepreneurship results—with no actual organizational differences—in an increase in positive attributions associated with a nonprofit organization, an effect we call the social entrepreneurship bias. We experimentally test for the existence of a social entrepreneurship bias by examining how the label of social entrepreneurship alters how people judge a nonprofit’s effectiveness and decide how to allocate scarce donation funds.
The Best Linear Unbiased Predictor (BLUP) in mixed models is a function of the variance components and they are estimated using maximum likelihood (ML) or restricted ML methods. Nonconvergence of BLUP would occur due to a drawback of the standard likelihood-based approaches. In such situations, ML and REML either do not provide any BLUPs or all become equal. To overcome this drawback, we provide a generalized estimate (GE) of BLUP that does not suffer from the problem of negative or zero variance components, and compare its performance against the ML and REML estimates of BLUP. Simulated and published data are used to compare BLUP. 相似文献
The purpose of this study wastwofold: (1) to analyze and explore theconceptual structure of subjective well-being(SWB), neuroticism (N) and extraversion (E);and (2) to compare the effect sizes of N and Eas predictors of SWB. The sample comprised 461participants representative of the adultpopulation in northern Norway. Analyses wereconducted by means of Structural EquationModeling (SEM), and the results on (1)supported the notion of an overall subjectivewell-being construct sustained by the threenested dimensions of life satisfaction,positive affect, and negative affect. A simplefactor structure for N and E was notsupported, and considerable modification wasneeded to provide even a mediocregoodness-of-fit for the trait model. On (2),N explained eight times as much of the SWBvariance as did E. Moreover, throughcomparison of several models it was revealedthat if E is the sole predictor of SWB, theinfluence of E on SWB is overestimated by afactor of seven. Since N and E are stronglyand negatively correlated (r = –0.50), themodel comparison demonstrates the importanceof including both E and N as independentvariables in regression models of SWB. 相似文献