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121.
From 1994 to 2003, New Zealands corporatized electricity lines networks operated with no industry regulator, but under the spotlight of mandatory information disclosure. As a result there exists a large body of detailed, audited and publicly available accounting data on the financial performance of these businesses. Using that data, this paper finds that price-cost margins have widened substantially since deregulation. We estimate the extent to which light-handed regulation has allowed profits to exceed the levels which would have been acceptable under the old rate-of-return regulatory framework, and find that the answer is about $200 million per year, on an ongoing basis.We thank colleagues at Victoria University, and two anonymous referees for this journal, for constructive comments on this paper. Any remaining errors are entirely our responsibility.JEL classification: D21; K23; L11; L43; L51 相似文献
122.
Jeffrey?P.?CarpenterEmail author Peter?Hans?Matthews Okomboli?Ong’ong’a 《Journal of Evolutionary Economics》2004,14(4):407-429
Recently economists have become interested in why people who face social dilemmas in the experimental lab use the seemingly incredible threat of punishment to deter free riding. Three theories with evolutionary microfoundations have been developed to explain punishment. We survey these theories and use behavioral data from surveys and experiments to show that the theory called social reciprocity in which people punish norm violators indiscriminately explains punishment best.JEL Classification:
C91, C92, D64, H41
Correspondence to: Jeffrey P. CarpenterWe thank Carolyn Craven, Corinna Noelke and two referees for comments, and Middlebury College for financial assistance. In addition, Carpenter acknowledges the support of the National Science Foundation (SES-CAREER 0092953). 相似文献
123.
Synopsis Classification is an important activity that facilitates theory development in many academic disciplines. Scholars in fields
such as organizational science, management science and economics and have long recognized that classification offers an approach
for ordering and understanding the diversity of organizational taxa (groups of one or more similar organizational entities).
However, even the most prominent organizational classifications have limited utility, as they tend to be shaped by a specific
research bias, inadequate units of analysis and a standard neoclassical economic view that does not naturally accommodate
the disequilibrium dynamics of modern competition. The result is a relatively large number of individual and unconnected organizational
classifications, which tend to ignore the processes of change responsible for organizational diversity. Collectively they
fail to provide any sort of universal system for ordering, compiling and presenting knowledge on organizational diversity.
This paper has two purposes. First, it reviews the general status of the major theoretical approaches to biological and organizational
classification and compares the methods and resulting classifications derived from each approach. Definitions of key terms
and a discussion on the three principal schools of biological classification (evolutionary systematics, phenetics and cladistics)
are included in this review. Second, this paper aims to encourage critical thinking and debate about the use of the cladistic
classification approach for inferring and representing the historical relationships underpinning organizational diversity.
This involves examining the feasibility of applying the logic of common ancestry to populations of organizations. Consequently,
this paper is exploratory and preparatory in style, with illustrations and assertions concerning the study and classification
of organizational diversity. 相似文献
124.
Daniel?W.?MccollumEmail author Kevin?J.?Boyle 《Environmental and Resource Economics》2005,30(1):23-33
Tests of convergent validity and procedural invariance were used to investigate whether individuals lacking direct experience with a commodity can provide valid responses to contingent-valuation questions eliciting ex post use values. Convergent validity between samples with and without experience was shown to hold for dichotomous-choice responses, but not for open-ended responses. 相似文献
125.
Price caps have been shown to have incentive properties superior to traditional rate of return regulation. Average-revenue-lagged regulation (ARL) is attractive in that steady-state prices are known to be efficient. We show that the ARL scheme can be manipulated by the firm so as to yield the unregulated global profit maximum. While tests exist that can provide the regulator with evidence of this strategic behavior, we also demonstrate that the unregulated global profit maximum will not be attainable if Laspeyres (L) regulation is employed.Jel classification: L43, L51I would like to thank Michael Crew and an anonymous referee for their extremely helpful suggestions. 相似文献
126.
The essay analyzes in an overlapping-generations model, to which extent a pay-as-you-go pension system will be the outcome
of majority voting, given specific institutional set-ups. Clearly, the vote of an active person depends on his expectations
about how the present decision (i.e., his contribution) is linked to the future (i.e., his benefits), when he will be retired.
In the paper we employ the assumption of a basic social contract where each active voter's future benefits are positively
related to his contributions. It is shown that in this framework a steady-state with a positive (though lower than optimal)
level of the pension system exists, even if a new majority decision about the system takes place every period. 相似文献
127.
Assessment of the Impact of Stormwater Characteristics on Clogging in Stormwater Filters 总被引:2,自引:0,他引:2
Harpreet?KandraEmail author David?McCarthy Ana?Deletic 《Water Resources Management》2015,29(4):1031-1048
Hydraulic conductivity of granular filter media and its evolution over time is a key design parameter for stormwater filtration and infiltration systems that are now widely used in management of polluted urban runoff. In fact, clogging of filter media is recognised as the main limiting factor of these stormwater treatment systems. This paper focuses on the effect of stormwater characteristics on the clogging of stormwater filters. Effect of five different operational regimes has been tested in this study of sediment concentration; pollutant concentrations; stormwater sediment size; loading rate and stormwater loading/dosing regime and compared with the Base case. For each operational condition, five column replicates were tested. Results suggest that sediment concentration in stormwater is a significant parameter affecting hydraulic and treatment performance, eventually affecting longevity of these stormwater treatment systems. Further, the size of sediments (and their relation to the size of filter media grains) in stormwater was found to be an important parameter to be considered in design of coarse filters with high infiltration rates that are used for stormwater treatment. As expected, the addition of metals and nutrients had limited or no contribution to changes in hydraulic or sediment removal performance of the studied stormwater filters. Whilst loading rate was found to be an important parameter affecting the hydraulic and treatment performance of these systems, any variation in the stormwater loading regime had a limited effect on their performance. This study therefore develops an understanding of the effect of catchment characteristics on design of filters and hence their longevity and maintenance needs. 相似文献
128.
In sulfate-reducing reactors, it has been reported that the sulfate removal efficiency increases when the COD/SO4(2-) ratio is increased. The start-up of a down-flow fluidized bed reactor constitutes an important step to establish a microbial community in the biofilm able to survive under the operational bioreactor conditions in order to achieve effective removal of both sulfate and organic matter. In this work the influence of COD/SO4(2-) ratio and HRT in the development of a biofilm during reactor start-up (35 days) was studied. The reactor was inoculated with 1.6 g VSS/L of granular sludge, ground low density polyethylene was used as support material; the feed consisted of mineral medium at pH 5.5 containing 1 g COD/L (acetate:lactate, 70:30) and sodium sulfate. Four experiments were conducted at HRT of 1 or 2 days and COD/SO4(2-) ratio of 0.67 or 2.5. The results obtained indicated that a COD/SO4(2-) ratio of 2.5 and HRT 2 days allowed high sulfate and COD removal (66.1 and 69.8%, respectively), whereas maximum amount of attached biomass (1.9 g SVI/L support) and highest sulfate reducing biofilm activity (10.1 g COD-H2S/g VSS-d) was achieved at HRT of 1 day and at COD/sulfate ratios of 0.67 and 2.5, respectively, which suggests that suspended biomass also played a key role in the performance of the reactors. 相似文献
129.
Based on results obtained in the laboratory a WWTP composed of a septic tank and an aerated percolating filter packed with organic media was built for a school. The system can treat 18 m3 d(-1) and was operated with a hydraulic loading rate of 0.078 (m3 m(-2) d(-1). For 360 days different operational conditions including start-up; stabilization; operation with aeration and non aeration; effect of rainy season, breaks from activities due to holidays and restart; were monitored and described in the article. Once stabilized, the system was able to remove, without the need for mechanical aeration, 97% of BOD5, 71% of COD, 93% of TKN, 11% of PO(4-)-P, 95% of TSS, 96% of VSS, in addition to having a removal efficiency of 4 log units of Faecal Coliforms (FC) and 100% helminthes eggs (HE). With this quality, the treated wastewater can be chlorinated and reused to irrigate green areas and/or in toilets. Although sanitary wastewater has a high concentration of Total-N (250 mg L(-1)) and a C/N ratio of less than 1, the system removed 65% of Total-N. Finally it was observed that after non activity periods, there was neither system failure nor the need to re-stabilize the system. 相似文献
130.
Bonenfant D Bourgeois FR Mimeault M Monette F Niquette P Hausler R 《Water science and technology》2011,63(12):2827-2832
Carboxymethylcellulose (CMC) and beta-cyclodextrin (beta-CD)-based polymers functionalized with two types of quaternary ammonium compounds (QACs), the alkaquat DMB-451 (N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride) (DMD-451) named polymer DMB-451, and FMB 1210-8 (a blend of 32 w% N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride and 48 w% of didecyldimethylammonium chloride) named polymer FMB 1210-8, were synthethized and characterized by Fourier transform infrared spectroscopy. The antimicrobial activities of these polymers against Eschericia coli were also evaluated at 25 degrees C in wastewater. The results have indicated that the polymer FMB 1210-8 possesses a high-affinity binding with bacterial cells that induces a rapid disinfection process. Moreover, in the same experimental conditions of disinfection (mixture of 1.0 g of polymer and 100 mL of wastewater), the polymer FMB 1210-8 has a higher antimicrobial efficiency (99.90%) than polymer DMB-451 (92.8%). This phenomenon might be associated to a stronger interaction with bacterial cells due to stronger binding affinity for E. coli cells and greater killing efficiency of the C10 alkyl chains QAC of polymer FMB 1210-8 to disrupt the bacterial cell membrane as compared to N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride. Together, these results suggest that the polymer FMB 1210-8 could constitute a good disinfectant against Escherichia coli, which could be advantageously used in wastewater treatments due to the low toxicity of beta-CD and CMC, and moderated toxicity of FMB 1210-8 to human and environment. 相似文献