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1.
An important initial step in accounting is mapping financial transfers to the corresponding accounts. We devised machine-learning-based systems that automate this process. They use word embeddings with character-level features to process transaction texts. When considering 473 companies independently, our approach achieved an average top-1 accuracy of 80.50%, outperforming baselines that exclude the transaction texts or rely on a lexical bag-of-words text representation. We extended the approach to generalizes across companies and even across different corporate sectors. After standardization of the account structures and careful feature engineering, a single classifier trained on 44 companies from 28 sectors achieved a test accuracy of more than 80%. When trained on 43 companies and tested on the remaining one, the system achieved an average performance of 64.62%. This rate increased to nearly 70% when considering only the largest sector.  相似文献   
2.
教育测量是指对教育现象的测量。教育测量的基本手段是存在失真范围的数量化分析。其数量化的语言是效度、信度等。效度分为效标效度与内容效度等,信度是表明测量可靠性的数量指标。  相似文献   
3.
Simple sufficient conditions for the existence of a unique equivalent martingale measure are provided. Furthermore, these conditions give us a handle on situations where an equivalent martingale measure cannot exist. The existence of a unique equivalent martingale measure is of relevance to problems in mathematical finance. Two examples of models for which the question of existence was unresolved are studied. By means of our results existence of a unique equivalent measure up to an explosion time is proved.  相似文献   
4.
Abstract. Many governmental programs are effective only if firms make costly investments. The inability of authorities to precommit to a regulatory scheme creates incentives for firms not to invest and to hold-up the regulator. This paper describes a simple subsidy/tax scheme embedded in a four-stage mechanism that solves the hold-up problem. We design a self-financing subsidy/tax scheme which benefits a complying firm at the expense of a non-complying firm. In order to be credible, the subsidy and tax rates must maximize social welfare for any combination of investment decisions. We show that there exists a unique subgame perfect equilibrium in which all firms invest and no actual implementation with subsidies and taxes is required. We discuss in which cases the mechanism can work under incomplete information. Received: 30 December 1998 / Accepted: 12 October 2001  相似文献   
5.
This article examines the puzzle of why futures prices continue to react to USDA crop reports despite the fact that reports appear to be no longer "newsworthy," that is, provide no better production estimates than private forecasts. The information value of reports is measured in terms of their influence on rational agents' harvest-time corn price expectations, which are uncovered using a Hamilton-type modeling approach. Results show that reports are still "newsworthy," as they would contribute to agents' price expectations if released a day early. Thus futures price reactions, which closely reflect price expectations, are rational and consistent with efficient markets hypothesis.  相似文献   
6.
Modeling Conditional Yield Densities   总被引:2,自引:0,他引:2  
Given the increasing interest in agricultural risk, many have sought improved methods to characterize conditional crop-yield densities. While most have postulated the Beta as a flexible alternative to the Normal, others have chosen nonparametric methods. Unfortunately, yield data tends not to be sufficiently abundant to invalidate many reasonable parametric models. This is problematic because conclusions from economic analyses, which require estimated conditional yield densities, tend not to be invariant to the modeling assumption. We propose a semiparametric estimator that, because of its theoretical properties and our simulation results, enables one to empirically proceed with a higher degree of confidence.  相似文献   
7.
West and Central Africa (WCA)’s cotton sector is experiencing rising production costs and lower yields, reversing decades of growth. Declining input use, soil fertility and inefficient chemical pest controls are contributing factors. We evaluate the potential impact of Bt cotton on WCA using a multiregion general equilibrium model and multicountry estimates of Bt-induced productivity. We find that Bt cotton raises growers’ returns, land value and welfare. Released labor from cotton is shifted to food crops hence reducing labor shortage constraints. Overall, results indicate that potential gross benefits from Bt cotton are substantial for WCA cotton sector, and that the economic costs of nonadoption are equally significant.  相似文献   
8.
Since its inception in the early 1980s, the success of China's enterprise reforms remains hotly debated. This paper introduces a new element into the analysis of state-owned enterprise performance by drawing on the recent increase in inter-regional income disparities. It is argued that as a result of less favourable structural conditions and stronger fiscal dependence on the central government, reform implementation in the interior provinces has lagged behind the progress made along the coast. This hypothesis is investigated using enterprise survey data from three interior provinces which is compared to a similar survey carried out earlier in four coastal cities. The evidence generally supports the view of larger administrative restrictions in the interior and relatively poor economic performance.  相似文献   
9.
从物流按地域属性分类切入,首先介绍了物流的地域属性,然后列出目前物流按地域属性分类的常见分法并对它们的不足之处详细分析,在此基础上,最后提出其科学的分类方法并对其中的概念进行一一解释。  相似文献   
10.
In this paper, we consider a continuum economy with a finite number of types of agent, and several private and public goods. The main result of the paper is that the graph of the equal-treatment Lindahl equilibria mapping is the unique abstract stable set with respect to the dominance relation in economies with crowding effects introduced by Vasil'ev et al. in 1995. The external stability of this mapping implies that, for any equal-treatment allocation x in , that is not a Lindahl equilibrium, there exists a subeconomy of such that one of its equal-treatment Lindahl allocations blocks x. This result is a counterpart of the theorem of Mas-Colell for Aumann's atomless market with private goods.  相似文献   
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