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81.
Abstract

New large-scale linked data are revolutionizing quantitative history and demography. This paper proposes two complementary strategies for improving inference with linked historical data: the use of validation variables to identify higher quality links and a simple, regression-based weighting procedure to increase the representativeness of custom research samples. We demonstrate the potential value of these strategies using the 1850–1930 Integrated Public Use Microdata Series Linked Representative Samples (IPUMS-LRS)—a high quality, publicly available linked historical dataset. We show that, while incorrect linking rates appear low in the IPUMS-LRS, researchers can reduce error rates further using validation variables. We also show how researchers can reweight linked samples to balance observed characteristics in the linked sample with those in a reference population using a simple regression-based procedure.  相似文献   
82.
海峡西岸城市群是中国经济快速发展的热点地区,研究其城市活力与城市扩张的耦合关系对促进城市建设意义重大。本研究以 DMSP-OLS 和 NPPVIIRS夜间灯光数据为数据源提取1992—2017年该城市群城市建成区,利用城市扩张率指数等对城市扩张的动态及其演变特征进行分析;应用熵值法、耦合协调度模型等评估城市活力,在此基础上,探究了对应城市活力和城市扩张耦合关系。结果表明:在研究期间,海峡西岸城市群城市建成区面积增加了23228.79km2;城市活力呈逐步逐年增加趋势;城市活力与城市扩张的耦合协调性逐步增强;经济发展和城市规划、地理区位优势等因素也对研究区城市活力与城市扩张及其耦合协调度的变化有影响。本研究可为城市群时空演变及其城市活力评价分析提供方法借鉴与数据支持。  相似文献   
83.
Abstract

Excavations at Ojakly (site 1744) in the Murghab alluvial fan in Turkmenistan mark the first systematic collection of archaeological materials related to Bronze Age mobile pastoralists in the region, and the earliest evidence to date of their occupation patterns, subsistence practices, and ceramic production activities. Because the appearance of mobile pastoral groups in the Murghab during the Late Bronze Age (ca. 1950–1500 b.c.) is traditionally associated with significant changes in regional sociopolitical structures, these data are important for establishing local strategies of and the relationship between sedentary agricultural and mobile pastoral populations. Here, we present ceramic, faunal, archaeobotanical, and lithic data that force us to reconsider the traditional sedentary-mobile dichotomy. Specifically, we find that while the subsistence economies are distinct at urban and non-urban sites, the ceramic production and trade interactions are significantly intertwined and more complex than previously acknowledged for this time period. Additionally, the presence of a ceramic kiln at Ojakly (Turkmen for “place with kiln”) containing unfired ceramics of a type typically associated with sedentary farmers in the Bronze Age Murghab suggests the transfer of technical knowledge between groups who nevertheless maintained distinct material cultural identities. Ojakly provides important new data about coexisting economies in the Late Bronze Age Murghab that can productively unsettle traditional notions of dominance, control, and polarization in sedentary-mobile interactions.  相似文献   
84.
This article evaluates six recent contributions to the literature on ethnographic research methods. Four concern collecting and analyzing texts, one introduces the use of textual and numerical data, and one illustrates the use of quantitative methods for qualitative data. The first four books reveal that current thinking in qualitative methods continues to privilege inexplicit criteria for data collection and analysis despite recognizing that explicit criteria work best. The last two books show how to effectively integrate qualitative and quantitative data in ways that resolve these contradictions.  相似文献   
85.
Searching, gathering, organizing, and retrieving data are basic tasks for historians. As long as historians work by themselves, decisions concerning data format, data exchange, computer platform, and the like remain secondary. Teams of historians often use relational databases for centralized data storage. However, fundamental risks are implicit when one uses databases. Among technical considerations, the process of transformation between the source and the database is a deciding factor. For those who gather data, the effective use of such possibilities as data exchange, compatibility, and simplicity of survey and the reuse of the data in other contexts and platforms becomes increasingly important. In contrast, the user's needs include the possibility of data verification and use of the data for more than one question. Many relational databases have considerable shortcomings because the stored data lose the visual characteristics, the syntax, and the semantics of the original source. The EuroClimHist database environment is a part of the NCCR Climate project. It uses a data tool, written in Java for the gathering of documentary data, which generates extensible markup language (XML) files for data exchange.  相似文献   
86.
Abstract

In this article, the author presents a strategy for designing relational databases with the program FileMaker Pro (FileMaker) to study the histories of individuals and organizations. The approach facilitates efficiency in inputting data and flexibility for constructing statistical analyses from the raw data. The key feature of the strategy is to define the basic unit of observation in the database in terms of an agent, an event, and a date. Given that programs such as FileMaker can easily sort data by agent and date, once one structures the data correctly, he or she can construct well-ordered event histories for agents, even if the researcher enters the data in an unordered fashion. By using events that happened to an agent at a particular time as the basic unit of observation, one maintains maximum flexibility to do statistical analysis that aggregates basic data in different ways. This article illustrates the power of the approach by outlining ways to analyze changes in geographic distances between two events marking the life histories of chemists.  相似文献   
87.
Abstract

Historians seeking to identify the Irish have overwhelmingly relied upon nominal record linkage, thus limiting studies to periods and contexts in which corroborating records exist. Surname analysis provides an alternative: a subset of 283 Irish surnames was able to correctly isolate 40 percent of known Irish individuals across thousands of entries, which is sufficient for sampling the Irish in demographic studies. This conclusion was based on an analysis of 278,949 names from the London area in the 1841 census, and was tested and refined against 42,248 historical records pertaining to the poor in London between 1777 and 1820.  相似文献   
88.
20世纪20年代由胡适发起的整理国故,以及随后由顾颉刚领头的古史辨运动等,对于中国近代历史学科发展,起到了不可忽视的推动作用。其最重要的贡献之一就是初步建立了对史料的选择、分析和运用的基本准则,并以此来促进历史叙述和书写的进步。身处这股浪潮当中的张荫麟,也逐步形成了自己的史料观念。这一过程由对疑古风气所带来的"求新好疑"的反思开始,进而发展到理想史料的择取和运用标准。而几十年前他对史料的深入分析,对于我们今日的史学研究也有一定的参考意义。  相似文献   
89.
This study developed an interview-based critical spatial thinking oral test and used the test to investigate the effects of Geographic Information System (GIS) learning on three components of critical spatial thinking: evaluating data reliability, exercising spatial reasoning, and assessing problem-solving validity. Thirty-two students at a large state university completed pre- and post-tests administered during the 2010 fall semester. This study found positive relationships between GIS learning and critical spatial thinking. We argue that the improvement can be attributed to students' experiences in a GIS course.  相似文献   
90.
This paper assesses the experience of undergraduate students using mobile devices and a commercial application, iSurvey, to conduct a neighborhood survey. Mobile devices offer benefits for enhancing student learning and engagement. This field exercise created the opportunity for classroom discussions on the practicalities of urban research, the survey data was available for immediate analysis, and students felt they were conducting meaningful research. The module experience supports recent research finding that mobile devices offer significant benefits for instructors, but using mobile devices also creates potential risks (to the students, equipment, and data) that must be considered while planning modules and during instruction.  相似文献   
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