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31.
    
In order to provide some thoughts and suggestions for future personalized education, this paper mainly analysis the background, opportunity, development and prospect of future personalized education under the background of big data era.On above foundation, the paper presents that future personalized education based on big data era will be a new tide of education.  相似文献   
32.
This paper contributes to a critical methodological discussion that has direct ramifications for policy studies: how computational methods can be concretely incorporated into existing processes of textual analysis and interpretation without compromising scientific integrity. We focus on the computational method of topic modeling and investigate how it interacts with two larger families of qualitative methods: content and classification methods characterized by interest in words as communication units and discourse and representation methods characterized by interest in the meaning of communicative acts. Based on analysis of recent academic publications that have used topic modeling for textual analysis, our findings show that different mixed‐method research designs are appropriate when combining topic modeling with the two groups of methods. Our main concluding argument is that topic modeling enables scholars to apply policy theories and concepts to much larger sets of data. That said, the use of computational methods requires genuine understanding of these techniques to obtain substantially meaningful results. We encourage policy scholars to reflect carefully on methodological issues, and offer a simple heuristic to help identify and address critical points when designing a study using topic modeling.  相似文献   
33.
杨京波 《旅游科学》2011,25(2):73-84
本文以中国旅游类上市公司为研究样本,利用其2004~2009年的非均衡面板数据建立计量经济学模型,采用混合最小二乘法对影响我国旅游类上市公司经营绩效的关键性公司治理因素进行实证检验。研究表明,旅游类上市公司的公司治理对其经营绩效具有显著影响。股权结构中管理层持股比例、第一大股东持股比例、第一大股东性质和前五位股东持股比例的平方和,以及第一大股东持股比例与第一大股东性质的交互项与公司经营绩效显著正相关,董事会特征中董事会规模与公司绩效显著正相关。  相似文献   
34.
In conventional approaches to computer analysis of historical sources, one must represent the data in structured formats in which content and context are discarded. Extensible markup language (XML), developed for data transfer on the Internet, permits preservation of the full text of irregular historical sources without sacrificing the ability to conduct systematic analysis. Related querying tools offer most functions of a relational database management system, including data transformation facilities for coding, standardizing, and aggregating nominal data. An XML database permits multiple interpretations of the data because the unit of analysis and the coding schemes are not defined at entry. In a case study of probate inventories, the author demonstrates how structured analysis of domestic interiors can be performed and introduces approaches to studying semistructured data.  相似文献   
35.
Differences in income between population groups in Finland have begun to increase since the recession of the early 1990s. These differences are examined here in terms of mean taxable incomes per household in 1989, 1993 and 1997 in 1 × 1 km grid cells, and the results are compared with those obtained using postal districts and municipalities as areal units. In spite of the increase, taxable income differences within municipalities are still relatively small. It is clear, however, that incomes have risen more in areas of increasing population than in areas of declining population. The results also indicate that the smaller the areal unit used, the greater the income differences, and vice versa. Thus the results of analyses based on different areal units cannot necessarily be regarded as comparable.  相似文献   
36.
Abstract

The aim of this paper is to discuss the long-term management of marine historic environment archives, focusing on the comparison of English Heritage’s National Record of the Historic Environment (NRHE) with the United Kingdom Hydrographic Office (UKHO) as case studies.

Within marine (and terrestrial) contexts, archaeological archives are unique records of survey, excavation, and associated research of the historic environment. They are a resource which allows understanding of the human past to be developed, reviewed, and reinterpreted as new data is gathered. As such, they are significant for research, development-led studies, education, outreach, and public enjoyment. At a time when there is a significant focus on data from the marine environment, both within the UK and more widely across Europe, this paper puts forward some initial recommendations to enable further interoperability between these two key national datasets.

Analysis of these datasets highlighted some interesting points, including the quantification and qualification of the scale of discrepancies between data providers (NRHE and UKHO), and how these can be overcome to allow comprehensive, reliable, and accessible data on which to base long-term planning, decision-making, and resource management. This will ensure a consistent approach, enabling the successful long-term management of historic environment archives, and making historic environment data readily accessible to the wider public.  相似文献   
37.
Abstract

This article describes the background and reconstruction of the Belgian 1961 census sample file. Recently, a complete codebook for the sample file has been drawn up, and the representativeness of the sample has been evaluated as accurate, except for the loss of cases that occurred for three Belgian subregions. With the addition of the 1961 census sample, cross-sectional microdata from the five successive population censuses since that year, covering a broad range of topics, are now available to the research community. The reconstruction of the 1961 census sample was part of the activities of the HISSTAT project, which is currently being run by a consortium of research institutions in Belgium to bring together cross-sectional aggregated data since 1800, aggregated longitudinal data since 1880, and cross-sectional microdata since 1961, all covering the entire country.  相似文献   
38.
Abstract

The authors argue that the publication of any new historical data series requires a formal estimate of its margins of error. We show how overall margins of error may be calculated for the standard forms of historical data series from information on the reliability of its components. The presentation of such margins of error should be transparent, allowing readers both to judge the estimate and to test the implications of applying different standards. An illustration is provided for Hoffmann's industrial output series for Britain, 1780–1831. The calculations emphasize the value of this approach to the recent debate on measuring growth rates during the British Industrial Revolution and suggest its merits more generally.  相似文献   
39.
The seismic vulnerability of city centers is commonly assessed by extending the study methods applied to single buildings to urban aggregations. This approach is not always applicable at territorial scale, as it is uneconomical in terms of time and costs. An innovative method provides reasonable large-scale a priori estimation of parameters not directly evaluable from the exterior of buildings by elaborating values which can be measured from the outside. Those parameters are treated as continuous variables, by assigning them a suitable probability density function. The Bayesian approach is adopted, which allows the update of initial hypotheses by using new data gathered during on-site surveys. In this regard, a rapid survey form for the on-site data collection is proposed. An example of its application to a façade of a building structural unit in Santo Stefano di Sessanio in L’Aquila province (Italy) is proposed, showing promising preliminary results for buildings belonging to Italian historical centers.  相似文献   
40.
The form of many Canadian cities has dramatically evolved over the past six decades due to urban sprawl. Several patterns can characterize this evolution including unlimited horizontal expansion of the city, leapfrog, and low‐density residential development at the outskirts, and widespread strip commercial and power centre retail development. Hamilton, Ontario is an example of a Canadian city that has experienced suburbanization and sprawled development for several decades. However, the nature of this sprawled development is unclear and its impact on urban form is not entirely understood. In this article, several hypotheses pertaining to sprawled land development and urban form are postulated and tested. The tests rely on point source data of the developed land parcels in Hamilton during the period 1950–2003. A number of spatial statistics techniques, including kernel estimation and complete spatial randomness (CSR) K‐function tests, are employed to examine the emerging nature of urban form. We hypothesize that while the city has been sprawling, the ongoing land development process is leading urban form into multinucleation. To support this assumption, we further hypothesize the existence of an interdependent spatial relationship between residential and commercial land uses at the emerging nuclei. Accordingly, we examine the strength of co‐clustering among these land use activities over time. The findings indicate that while the city has been sprawling, several consequent urban nuclei with mixed land use activities have been emerging and become more visible in recent years. This is an indication that the city's form is progressively becoming multinuclear. Furthermore, the estimates for the 1990s indicate interdependence between the locational patterns of residential and commercial land development. Co‐clustering between these two types of land uses is bi‐directional and occurs at a time lag of three to seven years. These findings affirm the existence of interdependence between land use activities at the observed nuclei, which support the emergence of a multinucleation.  相似文献   
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