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11.
The economic relevance of information systems has been studied for many years and has attracted an abundance of research papers. However, the “productivity paradoxon” of the 1990s, Carr’s widely recognized paper “IT doesn’t matter”, and several studies that do not find a positive correlation between IS investments and economic performance reveal long-lasting difficulties for IS researchers to explain “IS business value”. Business executives and researchers also continue to question the value of IS investments. This raises the question of whether literature reviews have tapped their potential to address the concerns by covering key research areas of IS business value and preserving their key findings. In order to address this question, this paper identifies and describes 12 key research areas, and synthesizes what literature reviews published in pertinent academic outlets have done to preserve knowledge. The analysis of 22 literature reviews shows that some crucial areas have not been (sufficiently) covered. They provide fertile areas for future literature reviews. As this work is based on the results of more than 200 research papers, it is capable of drawing a comprehensive picture of the current state-of-the-art in IS business value research.  相似文献   
12.
The objective of this study was to examine the effect of global–local interactions on food production and consumption in Ghana, and identify possible local solutions. Primary data were collected using a combination of quantitative‐qualitative methods, which included focus group discussions and one‐on‐one interviews. Approximately 450 household heads were randomly selected and interviewed between August 2007 and August 2008 in Eastern, Central, Upper East and Northern Regions of Ghana. Findings revealed increasing consumption of foreign rice as opposed to decreasing consumption of local rice and other staples like millet, sorghum and yam because of global–local interactions. However, opportunities exist to re‐localize production‐consumption patterns through the use of ‘glocal foods’ like improved ‘koose and waakye’. Referencing the situation in Ghana, the study recommends improved production and processing practices backed with appropriate technologies that reflect changing consumption dynamics in order to take full advantage of opportunities created as a result of global–local interactions.  相似文献   
13.
This study develops an R&D-based growth model with vertical and horizontal innovation to shed some light on the current debate on whether patent protection stimulates or stifles innovation. We analyze the effects of patent protection in the form of blocking patents. We show that patent protection changes the direction of innovation by having asymmetric effects on vertical innovation (i.e., quality improvement) and horizontal innovation (i.e., variety expansion). Calibrating the model and simulating transition dynamics, we find that strengthening the effect of blocking patents stifles vertical innovation and decreases economic growth but increases social welfare due to an increase in horizontal innovation. In light of this finding, we argue that in order to properly analyze the growth and welfare implications of patents, it is important to consider their often neglected compositional effects on vertical and horizontal innovation.  相似文献   
14.
Since the second half of the past century, increasingly flexible organizational forms have been appearing among firms. However, while hierarchies are easily described, too few mathematical tools are available for flexible organizations. In this article, two measures are proposed in order to assess the state and trend of flexible organizations. The first of these measures is based on information waste, which occurs whenever information is classified into categories. The second measure is based on duplication of operations. The underlying idea is that firms have an endogenous drive towards organizational configurations where waste of information and duplication of operations are minimized. However, environmental uncertainty may require some flexibility, which is ensured by cognitive processes that discard some information as well as by parallel undertaking of similar actions.  相似文献   
15.
Evidence Theory is a branch of the mathematics of uncertain reasoning that entails profound epistemological differences with respect to Probability Theory. In fact, its paradigmatic situation is the judge who must evaluate testimonies, rather than the gambler who must evaluates odds. Unlike a gambler, who faces a definite set of possibilities, a judge maybe forced to change her evaluation because of novel possibilities suggested by unexpected testimonies. In this sense, Evidence Theory provides a formalization of some among Shackles intuitions. While the details of the connections between Shackle's theory and Evidence Theory have been explored elsewhere, this article is devoted to a detailed explanation of the working of Evidence Theory. An example is discussed in detail and several domains of application are briefly sketched.  相似文献   
16.
In the Generalized Bin Packing Problem (GBPP), given two sets of compulsory and non-compulsory items characterized by volume and profit and a set of bins with given volume and cost, we want to select the subset of profitable non-compulsory items to be loaded together with the compulsory ones into the appropriate bins in order to minimize the total net cost. Lower and upper bounds to the GBPP are given. The results of extensive computational experiments show that the proposed procedures are efficient and the bounds are tight.  相似文献   
17.
Seguendo l'impostazione predittiva delineata da J. Aitchison e I. R. Dunsmore (1975) viene proposto un modello non-parametrico di analisi discriminatoria dal punto di vista bayesiano.Si ricorre a tal fine ad una versione modificata dello schema di scambiabilità parziale e si utilizza il processo «mistura di prodotti di processi di Dirichlet» introdotto da D. M. Cifarelli ed. E. Regazzini (1978). Si presenta infine un'applicazione del modello ad un tipico problema di diagnosi medica.
J. Aitchison and I. R. Dunsmore (1975) have stressed the importance of the predictive distribution for the solution of classical statistical problems. Following this approach we show initially how a modified version of the model of partial exchangeability can be usefully applied to derive the so called diagnostic distribution. Subsequently a nonparametric model of discriminatory analysis is derived, wherein a crucial role is played by a particular process named «mixture of products of Dirichlet processes» introduced by D. M. Cifarelli and E. Regazzini (1978) following a paper by C. E. Antoniak (1974) which in turn generalized the well known Dirichlet process developed by T. S. Ferguson (1973). Finally a numerical application to a medical problem is provided.


Versione definitiva pervenuta il 24-9-81

Lavoro eseguito nell'ambito del GNAFA-CNR. L'argomento di questo lavoro mi è stato suggerito dal professor Eugenio Regazzini. A quest'ultimo ed al prof. Donato Michele Cifarelli sono grato per avermi segnalato alcune oscurità nel testo originario.  相似文献   
18.
An input–output (IO) system which is capable of producing any semi-positive net product by an adequate choice of the activity levels of its processes satisfies the ‘adjustment’ property. We analyze under which conditions the adjustment property holds for IO systems in which some produced goods have a purely intermediate character. The peculiarity of these pure capital goods is that final demand for them is identically zero. One of the ways to deal with this type of system is to eliminate the pure capital goods, by means of vertical integration.  相似文献   
19.
The aim of the present study is to examine the role of ethical dimensions and product personality in the purchasing intention of organic food products. The Prospect method (Caprara et al. in Test Psicomet Metodol 7(3–4):113–128, 2000), which integrates the Five factors model of personality (cf. Digman in Annu Rev Psychol 41(1):417–440, 1990) and the Theory of planned behavior (Ajzen in Organ Behav Hum Decis Process, 50(2):179–211, 1991) extended to an ethical dimension, was employed, by using a Structural Equation Modeling approach. Results showed that moral norms—i.e., personal beliefs regarding what is right or wrong (Parker et al. in Br J Soc Psychol, 34(2):127–137, 1995)—can be considered the main motivator of purchasing intention, and they are, in turn, affected by subjective norms and product personality traits of Naturalness and Authenticity. Marketing implications for firms operating in the organic food industry are discussed, in their intent to shift from a “niche” market to a broader diffusion of these products.  相似文献   
20.
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