基于微博数据的北京市热点区域意象感知

“城市意象”研究对城市文化感知、城市管理与规划、旅游资源开发等具有重要意义。近年来,随着智能移动终端和社交媒体的普及,产生了大量城市内包含有文本和地理位置等信息的社交媒体数据,涉及城市的各个区域,为开展城市意象的综合感知研究提供了新的途径。本文以2016年北京市带位置签到的新浪微博数据为例,在空间聚类发现热点区域的基础上,采用词频—逆文件频率(TF-IDF)与文档主题生成模型LDA两类典型的文本分析的方法,挖掘城市不同热点区域的主题,以感知北京市不同热点区域的社会文化功能和人群行为,并在此基础上通过对热点区域高频主题词进行共词聚类分析,深度挖掘北京市的总体意象。研究表明,运用文本挖掘及地理大数据分析的城市意象研究方法,能及时感知人群在城市不同场所的活动、态度、偏好,从而揭示城市的社会文化及功能特征,是对刻画城市物质形态的城市意象五要素模型的重要补充。此外,以北京市热点区域为例的实证研究结果对现实中的城市特色传承与空间品质塑造等有一定的启发意义。

Image perception of Beijing's regional hotspots based on microblog data

Research on "city image" can facilitate urban culture perception, urban management and planning, and tourism resource development. In recent years, as intelligent mobile terminals and social media apps became increasingly popular, a large number of social media geo-tagged data containing text and location information have been generated, providing a new solution for city image perception studies. This article uses the social media geo-tagged data (Sina weibo check-in data in Beijing, 2016) to explore regional hotspots through spatial clustering, and mining the topics of different hotspots through two typical methods— term frequency-inverse document frequency (TF-IDF) and latent Dirichlet allocation (LDA). The results reflect the topics that users were concerned about and discussed in different places, revealing the culture, functions, and characteristics of diverse places of Beijing in great depth. The proposed city image abstraction approach by integrating text mining and spatiotemporal big data analysis can promptly expose the differences on themes of activities, attitudes, and preferences in different places in Beijing, thus reveal the social and cultural characteristics of the city. Our method is an important complement to the five-element model of city image, which focuses on the urban material form. In addition, the case study results of Beijing regional hotspots facilitate the preservation of city characteristics and shaping of space quality.