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11.
ABSTRACT

Natural language query systems over RDF data need to rely on the semantic relations in query. First, we propose the new crowdsourcing model that used to produce semantic relations dataset. The model not only inherits completeness of the iterative model and accuracy of the parallel model, but also saves human resources. Second, we mine the rules of semantic relation recognition from the correlations between dependency structures and semantic relations. Third, we propose an algorithm of semantic relation recognition for natural language query over RDF data, and experiments demonstrate that it can recognize more semantic relations than existing methods.  相似文献   
12.
In this paper, we consider the feasibility of constructing online sentiment indices, using large amounts of media data, as an alternative to the conventional survey method used to create the consumer confidence index in South Africa. A clustering framework is adopted to provide an indication of possible candidate sentiment indices constructed from a combination of different text sources and dictionaries that best mimic the traditional survey-based consumer confidence index from the South African Bureau for Economic Research (BER). The results conclude that it is possible to create an index using sentiment analysis using online editorial data that does resemble the BER’s consumer confidence index. The different media-based sentiment indices (MSI) show a significant level of correlation and co-movement with the BER’s CCI. Impulse responses and cross-correlation functions indicate that the MSI could potentially lead the survey-based method up to two quarters. Furthermore, Granger-causality tests show that the media-based indices are good predictors of future consumer confidence index values. The results provide motivation for further study on the use of sentiment-based techniques and online media data sources to track consumer confidence within an emerging market such as South Africa.  相似文献   
13.
This paper reviews some recent blockchain‐based applications for information capture, distribution and preservation. As part of that review, this paper examines two key concerns with current blockchain designs for accounting and supply chain transactions: data independence and multiple semantic models for the same information distribution problem. Blockchain applications typically integrate database, application and presentation tiers all in the same ledger. This results in a general inability to query information in the ledger and other concerns. Further, since most applications appear to be private blockchain applications, there is a concern of agents needing to accommodate multiple blockchains depending on who their trading partners are and what they request. Finally, this paper uses a distributed database to design a ‘blockchain‐like’ system for virtual organizations.  相似文献   
14.
What if a popular dataset that has generated a large amount of literature has been misunderstood and has led to misleading inferences? This paper examines household expenditure data from the Indonesian National Socio-economic Survey (Susenas), which started more than 50 years ago. Appropriate use of Susenas data for policy analysis requires an understanding that the survey’s expenditure variable does not measure true out-of-pocket expenses, because it includes subsidies received by households when obtaining goods and services. We also highlight an abrupt change in the survey instrument that occurred in 2015, when the reference period for certain items was extended. For health items, this generated a change in the expenditure series that can be misinterpreted as being the result of a social health insurance reform introduced in 2014 to lower the health care burden on households. Accordingly, we propose a way to account for this artificial expenditure movement in Susenas.  相似文献   
15.
By using panel data analysis across 368 water utilities in Mexico over the period 2010–2014, we find that small firms are more efficient than medium and large providers and that increasing production is associated with less efficiency. Billing, income collection and profitability are relevant factors to improve efficiency. Medium and large firms require to measure consumption by service with meters in order to increase efficiency, while small firms do not require it.  相似文献   
16.
In rational, efficiently functioning and complete markets, returns on derivative and underlying securities should be perfectly contemporaneously correlated. Due to market imperfections, one of these markets may reflect information faster. The use of high-frequency data and the choice for a small unit time interval to measure these lead-lag relations comes at the cost of some or many missing observations, causing traditional estimators to either under- or overestimate covariances and correlations. We use a new estimator to estimate lead-lag relationships between the cash AEX index, options and futures. We find that futures returns lead both options and cash index returns by approximately 10 minutes. The relationship between options and the cash market is not completely unidirectional.  相似文献   
17.
李哲 《嘉兴学院学报》2005,17(3):131-133
该文对嘉兴市6个年级共600个小学生的人体测量数据,进行了统计分析,探讨了男女小学生体型随年龄变化的规律。  相似文献   
18.
十七大报告、牡丹江市第十次党代会报告和十届四次全会报告中都提到区域经济协调发展的问题,这是一个关系国家、地区发展的重要战略。本文结合三个报告和大牡丹江战略来阐述区域经济一体化在牡丹江的实践。  相似文献   
19.
We employ panel data as well as country-specific models to uncover empirically the determinants of current account imbalances. We find evidence of slope heterogeneity likely rendering the fixed-effect estimator inconsistent. Mean group estimation is followed to overcome the latter difficulty. Both estimation techniques are evaluated by means of in- and out-of-sample criteria. The mean group estimator outperforms the fixed-effect approach and, moreover, only three economic variables are found to impact on the current account balance significantly. These are the government budget balance, the domestic output gap and the changes of the terms of trade. We finally propose a parsimonious dynamic model of the current account, including only these variables and illustrate that it has similar predictive accuracy as country-specific benchmark models. JEL no. F32, C23, C53  相似文献   
20.
结合制度环境深入考察了多个大股东的行为选择及其作为一种治理机制的有效性问题,我们发现,多个大股东的公司治理作用只有在特定的制度环境下才是有效的,而在制度环境很不完善的条件下,外部大股东的监督是不存在或者说多个大股东的公司治理作用是无效的。  相似文献   
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