On the Geometry of Null Polygons in Full N=4 Superspace

We discuss various formulations of null polygons in full, non-chiral N=4 superspace in terms of spacetime, spinor and twistor variables. We also note that null polygons are necessarily fat along fermionic directions, a curious fact which is compensated by suitable equivalence relations in physical theories on this superspace.Comment: 25 pages, v2: comment on correlation functions adde

An application of the two-stage, semi-parametric approach with double bootstrap to analyze technical efficiency of Critical Access Hospitals

This study examines technical efficiency of Critical Access Hospitals (CAH) using a two-stage approach and bootstrap procedures for making valid inference about the impact of environmental variables on CAH efficiency. In the first stage, a data envelopment analysis (DEA) efficiency estimator is used to estimate technical efficiency of each hospital in the sample. In the second stage, efficiency scores are regressed on environmental variables using a truncated regression with bootstrap. Alternatively, a double bootstrap procedure is used, where bias-corrected DEA efficiency scores, obtained by means of bootstrap in the first stage, are used in the second stage bootstrapped truncated regression. While both procedures provide valid inference in the second stage analysis, the double bootstrap procedure has also been shown to improve statistical efficiency in the second stage truncated regression. Our results indicate that, while the two procedures yield in general similar and consistent results, only the double bootstrap procedure unveiled the direct association between Medicare cost-based reimbursement and CAH inefficiency.Critical Access Hospitals, efficiency, two-stage approach, bootstrap, Health Economics and Policy,

Forms of presentation for synthesis documents of managerial accounting. Advantages for decision making processes

The paper presents potential forms of presentation for synthesis documents of managerial accounting in Romania. There are analyzed construction models of results accounts relating to total and partial methods identified within enterprises in Romania, which are accompanied by comments of the authors regarding the way of preparation, presentation, assessment, interpretation of the obtained results, as well as their advantages and disadvantages. There are also presented the models of annexes accompanying results account, intended to highlight deviations, cost analysis. The article ends with the authors' point of view about the models approached and analyzed.Results account; Activity-Based Costing; model; synthesis documents; managerial accounting

Efficiency Analysis of Rural Hospitals: Parametric and Semi-parametric Approaches

This paper examined cost efficiency differences between rural hospitals participating in the Critical Access Hospital (CAH) Program and a group of non-converting, prospectively paid rural hospitals using both a two-stage semi-parametric approach as well as stochastic frontier analysis (SFA). CAHs receive Medicare cost-based reimbursement, in contrast with the rest of the hospitals reimbursed under Medicare prospective payment system (PPS). However, cost-based reimbursement has been associated with inefficiency in hospital operations and, consequently, concerns have been raised about the efficiency of CAHs. Results showed a positive and significant effect of CAH status on cost inefficiency under both model specifications suggesting that CAHs were less cost efficient than non-converting rural hospitals.rural hospitals, efficiency, SFA, two-stage approach, Community/Rural/Urban Development, Health Economics and Policy, Production Economics, Productivity Analysis, Public Economics, Research Methods/ Statistical Methods, I18,

Determinants of Cost Inefficiency of Critical Access Hospitals: A Two-stage, Semi-parametric Approach

This study examines, post-conversion, cost inefficiency of Critical Access Hospitals (CAH) using a two-stage approach. While the results suggest that Medicare cost-based reimbursement and longer participation in the CAH program may increase the cost inefficiency of CAHs, the extent of this inefficiency increase is lower than what previous literature showed.Critical Access Hospitals, cost inefficiency, two-stage approach, bootstrap, Community/Rural/Urban Development, Health Economics and Policy, Production Economics, I18,

WHO BENEFITS FROM FUNDS OF HEDGE FUNDS? A CRITIQUE OF ALTERNATIVE ORGANIZATIONAL STRUCTURES IN THE HEDGE FUND INDUSTRY (I)

This paper provides a critique of alternative organizational structures in the hedge fund industry. Our critique is facilitated by several stylized models describing alternative industry structures. The models include: (1) An insideonly hedge fund model; (2) A straddling hedge fund model; (3) A straddling “feeder” fund of funds (FOF) hedge fund model; (4) A stand-alone outside hedge fund; and (5) An outside “feeder” FOF hedge fund model. Our discussion of these models, which centers on benefits vs. fundamental problems related to illiquidity, information asymmetry, and conflicts of interest, leads to several hypotheses about the differential characteristics and return performance of both individual hedge funds and FOFs.Hedge funds, Funds of funds, Illiquidity, Information asymmetry, Conflicts of interest, Adjacency risk, Contagion, Return performance

The importance of activity-based costing method (ABC) In Romania's business environment changes

The purpose of this paper is to present the importance of Activity-Based Costing method (ABC) in Romania's business environment changes. We analyzed the possibilities to adapt to a modern management accounting method and managerial accounting organization assumptions of the ABC (Activity-Based Costing) method in Romanian enterprises. The article ends with the authors' conclusions about the changes of the ABC method in the Romanian’s business environment.Activity-Based Costing; management accounting; entity; implementation; business environment

Analyzing the cost of harvesting and the economic structure of Florida grouper fishery

This study uses a translog cost function to investigate the technical and economic relationships present among a sample of Florida grouper longline vessels. The existence of jointness-in-inputs and non-separability between inputs and outputs suggests that resource management should be based on multiproduct production theory, and that explicit recognition of the economic interactions among species should be incorporated in any regulatory process. The cross-price elasticities of input demands showed substitution relationships between input pairs, implying that imposed regulation on the single input will be compensated for by increases in the other inputs. Furthermore, model results showed apparently substantial economies of scope, especially between red grouper and most of the other species in the grouper fishery, product specific economies of scale and multiproduct economies of scale. The technical and economic interrelationships inferred from this study suggest that individual species regulation can generate economic inefficiency by inducing nonoptimal input and output mixes

Analyzing Differences in Rural Hospital Efficiency: A Data Envelopment Analysis Approach

This study analyzes difference in efficiency among the U.S. rural hospitals using a two-stage, semi-parametric approach. Data Envelopment Analysis is used in the first stage to calculate cost, technical and allocative efficiencies of Critical Access Hospitals (CAH) and non-CAH rural hospitals. Following Simar and Wilson (2007), bootstrapped truncated regressions are used in the second stage to infer on relationship between the cost, technical and allocative inefficiencies of hospitals and some environmental variables. The estimated results show that CAHs are less cost, technical and allocative efficient than non-CAH rural hospitals. The results also show that Medicare cost-based reimbursement for CAHs has a negative effect on the efficiency of these hospitals while Medicare prospective payment system for non-CAH rural hospitals has a positive effect on hospital efficiency.efficiency, two-stage, semi-parametric, bootstrap, data envelopment analysis, Health Economics and Policy, I12, I18,