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61.
The paper hypothesizes that diversification by firms based in the pharmaceutical industry during the 1977-86 time period was primarily undertaken to reduce the risks associated with being dependent upon a technologically dynamic environment. Consistent with this non-efficiency motive for diversification, declining economic performance is predicted. A longitudinal empirical analysis provides support for these propositions. 相似文献
62.
This paper discusses the statistical issues that arise in conducting an economic damages analysis in the context of a litigation matter involving copyrights. Calculating damages in copyright cases turns out to be a natural application for econometric modelling methods. Surprisingly, elementary statistical issues can be a source of significant debate between the experts in such matters. In this paper, we present a case study and illustrate how issues such as interpretation of p -values and what "rejection of the null hypothesis" really "means" in such matters. 相似文献
63.
A tariff system has been set up for the largest wastewater treatment plant in South-East Asia, the Samut Prakarn Wastewater Treatment Plant south of Bangkok, which is currently under completion. Fully functional the plant will have a design capacity for 500,000 m3 per day and will service a combined residential and industrial area with approximately 600,000 residents and 2,300 factories. The tariff system, which includes a tariff model, is based on water consumption and BOD load. As background for setting the tariffs a comprehensive monitoring system including an industrial permitting system has been developed. The paper presents the background and rationale for setting up the system as well as the objective, scope and content of the tariff system and the industrial permit system. Further, the feasibility of introducing cost recovery systems, which is widely accepted in developing economies on the conceptual level and to some extent implemented at the legal and regulatory level, but has yet to be implemented at large, is discussed. 相似文献
64.
In this study, nitrogen removal was investigated in pilot-scale subsurface flow (SSF) and in free water surface flow (FWS) constructed wetlands installed in the campus of TUBITAK-Marmara Research Center, Gebze, near Istanbul, Turkey. The main purposes of this study are to apply constructed wetlands for the protection of water reservoirs and to reuse wastewater. Experiments were carried out at continuous flow reactors. The effects of the type of plants on the removal were investigated by using emergent (Canna, Cyperus, Typhia spp., Phragmites spp., Juncus, Poaceae, Paspalum and Iris.), submerged (Elodea, Egeria) and floating (Pistia, Salvina and Lemna) marsh plants at different conditions. During the study period HLRs were 30, 50, 70, 80 and 120 L m(2)d(-1) respectively. The average annual NH4-N, NO(3)-N, organic N and TN treatment efficiencies in SSF and FWS wetlands are 81% and 68%, 37% and 49%, 75% and 68%, 47% and 53%, respectively. Nitrification, denitrification and ammonification rate constant (k20) values in SSF and FNS systems have been found as 0.898 d(-1) and 0.541 d(-1), 0.488 d(-1) and 0.502 d(-1), 0.986 d(-1) and 0.908 respectively. Two types of the models (first-order plug flow and multiple regression) were tried to estimate the system performances. 相似文献
65.
66.
V. M. Boyarskii L. P. Mikhailov I. S. Sheinin 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(10):623-627
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 11–13, October, 1992. 相似文献
67.
This paper models the demand for stockbrokers' services in Australia, consisting of two related services, agency trades and principal trades. The relationship between agency and principal trades is estimated. The results indicate that the two services are complements rather than substitutes. Using unique accounting information, a model of agency and principal trading activities is estimated to determine the welfare effects of (i) deregulating brokerage commissions and (ii) a ban on principal trading by brokers. The results show a sizeable welfare gain to investors (amounting to about 60% of the gross revenue of brokers) stemming from deregulation of the minimum charge for agency trades. The loss in profitability by brokers due to deregulation is also computed and shown to be negligible. The results also show that due to complementarity, a ban on principal trading, even with deregulation of agency trading, can impose an arbitrarily high cost on investors which could, in principle, offset the gains from agency deregulation. 相似文献
68.
We examine investment behavior among exchange-listed Korean manufacturing firms before and after the 1997 financial crisis using firm-level panel data. Starting with the standard Q-theory of investment, we augment it by allowing for a sales accelerator and the possibility of cash constraints, categorizing firms based on their age, size and affiliation to an industrial conglomerate (i.e., chaebol). We find that Tobin’s Q is a robust determinant of investment in a pooled sample for 1992–2001, but that it became more important for small firms and less important for chaebol-affiliated firms after the crisis. Investment by chaebol firms also became more sensitive to the availability of internal cash balances after the crisis. We interpret this as reflecting a shift in the Korean economy to a stronger market orientation after the crisis and to a business climate in which the quality of potential projects became more important relative to capital market imperfections in determining the destination of investment funds. 相似文献
69.
Based upon a review of the extant literature, it is proposed that the structure of an interorganizational relationship is composed of relationship type and the under‐researched construct of relationship magnitude. Specifically, it is hypothesized that relationship magnitude, a second order construct composed of trust, commitment, and dependence, affects relationship type, which affects the perception of value of the relationship. The results of a survey analyzed through structural equation modeling support these hypotheses. 相似文献
70.
This paper examines whether firms which delay earnings announcements engage in earnings management. The cross–sectional version of the modified Jones 1995 model is used to estimate 'normal' accruals. Prior research has documented that, on average, delayed earnings announcements are associated with negative earnings surprises. Our evidence suggests that the market anticipates unfavorable earnings news when it observes reporting delays. As a consequence, late reporters appear to make the most of a bad situation by employing income–decreasing accruals in big–bath–type earnings management and in contractual renegotiations. We find that the magnitude of income–reducing abnormal accruals is related to the reporting lag. 相似文献