Search results for "cluster analysi"
showing 5 items of 865 documents
Scalable implementation of dependence clustering in Apache Spark
2017
This article proposes a scalable version of the Dependence Clustering algorithm which belongs to the class of spectral clustering methods. The method is implemented in Apache Spark using GraphX API primitives. Moreover, a fast approximate diffusion procedure that enables algorithms of spectral clustering type in Spark environment is introduced. In addition, the proposed algorithm is benchmarked against Spectral clustering. Results of applying the method to real-life data allow concluding that the implementation scales well, yet demonstrating good performance for densely connected graphs. peerReviewed
Axiology of the historial city and the cap rate. The case of the old town of Ragusa Superiore
2017
Il contributo affronta il tema del ruolo che il mercato immobiliare assume nei processi di valorizzazione dei tessuti urbani storici nella logica dell’approccio al valor capitale. L’articolazione, eterogeneità e multi-contestualità del patrimonio immobiliare della città storica, la molteplicità delle relazioni tra valori e prezzo, la complessa dialettica fondo/flusso, l’eterogeneità dei profili dei soggetti economici che interagiscono nel mercato, danno vita ad un assortimento di approcci all’investimento immobiliare che in questo contributo, attraverso l’analisi del saggio di capitalizzazione si intendono rappresentare. La convergenza tra valori di contesto e potenzialità inespresse da una…
Application of the Information Bottleneck method to discover user profiles in a Web store
2018
The paper deals with the problem of discovering groups of Web users with similar behavioral patterns on an e-commerce site. We introduce a novel approach to the unsupervised classification of user sessions, based on session attributes related to the user click-stream behavior, to gain insight into characteristics of various user profiles. The approach uses the agglomerative Information Bottleneck (IB) algorithm. Based on log data for a real online store, efficiency of the approach in terms of its ability to differentiate between buying and non-buying sessions was validated, indicating some possible practical applications of the our method. Experiments performed for a number of session sampl…
Identifying the Sales Patterns of Online Stores with Time Series Clustering
2018
Electronic commerce, especially in the business-to-consumer (B2C) context, has for years been a popular research topic in information systems (IS). However, the prior research on the topic has traditionally been dominated by the consumer focus instead of the business focus of online stores. For example, whereas various segmentations exist for online consumers based on their purchase behaviour, no such segmentations have been developed for online stores based on their sales patterns. In this study, our objective is to address this gap in prior research by identifying the most typical sales patterns of online stores operating in the B2C context. By using self-organising maps (SOM) to analyse …
Relationship between trophic state and plankton community structure in 21 Sicilian dam reservoirs
1994
The relationship between the trophic state of 21 Sicilian dam reservoirs and their taxonomic community structure of phytoplankton (87 taxa) as well as zooplankton (45 taxa) have been examined by means of cluster analysis performed using annual average biomass values. The phytoplankton community structure was closely connected with the trophic state of the reservoirs, whereas the zooplankton community structure was related to hydrological regimes peculiar to the individual water bodies and not to the trophic state. © 1994 Kluwer Academic Publishers.