Intelligent Self-Repairable Web Wrappers

The amount of information available on the Web grows at an incredible high rate. Systems and procedures devised to extract these data from Web sources already exist, and different approaches and techniques have been investigated during the last years. On the one hand, reliable solutions should provide robust algorithms of Web data mining which could automatically face possible malfunctioning or failures. On the other, in literature there is a lack of solutions about the maintenance of these systems. Procedures that extract Web data may be strictly interconnected with the structure of the data source itself; thus, malfunctioning or acquisition of corrupted data could be caused, for example, by structural modifications of data sources brought by their owners. Nowadays, verification of data integrity and maintenance are mostly manually managed, in order to ensure that these systems work correctly and reliably. In this paper we propose a novel approach to create procedures able to extract data from Web sources -- the so called Web wrappers -- which can face possible malfunctioning caused by modifications of the structure of the data source, and can automatically repair themselves.\u

Web Data Extraction, Applications and Techniques: A Survey

Web Data Extraction is an important problem that has been studied by means of different scientific tools and in a broad range of applications. Many approaches to extracting data from the Web have been designed to solve specific problems and operate in ad-hoc domains. Other approaches, instead, heavily reuse techniques and algorithms developed in the field of Information Extraction. This survey aims at providing a structured and comprehensive overview of the literature in the field of Web Data Extraction. We provided a simple classification framework in which existing Web Data Extraction applications are grouped into two main classes, namely applications at the Enterprise level and at the Social Web level. At the Enterprise level, Web Data Extraction techniques emerge as a key tool to perform data analysis in Business and Competitive Intelligence systems as well as for business process re-engineering. At the Social Web level, Web Data Extraction techniques allow to gather a large amount of structured data continuously generated and disseminated by Web 2.0, Social Media and Online Social Network users and this offers unprecedented opportunities to analyze human behavior at a very large scale. We discuss also the potential of cross-fertilization, i.e., on the possibility of re-using Web Data Extraction techniques originally designed to work in a given domain, in other domains.Comment: Knowledge-based System

Keterkinian Solusi Wrapper

Kata 'wrapper' berasal dari komunitas database. Suatu wrapper di dalam konteks ini digunakan sebagai suatu penengah/mediator antara beberapa database dan satu aplikasi [5]. Dengan cara yang serupa, di dalam lingkungan web suatu wrapper mengkonversi informasi dari dokumen HTML ke dalam informasi yang tersusun (seperti XML). Informasi yang tersusun dapat disimpan untuk penggunaan berikutnya, seperti menjawab query-query, atau menghasilkan secara dinamis atas permintaan melalui suatu antar muka Web atau dari satu aplikasi. Saat ini beberapa perusahaan menggunakan informasi yang tersedia di Web untuk sejumlah tujuan. Namun demikian kebanyakan dari informasi ini hanyalah tersedia dalam bentuk dokumen HTML. Untuk mengatur data Web secara efektif, seorang pengguna perlu untuk mengekstrak informasi terkait, memahami struktur semantiknya, dan mengkonversinya ke format yang diinginkan. Baru-baru ini, beberapa teknik- teknik yang mengizinkan informasi dari Web untuk secara otomatis di-ekstrak telah digambarkan. Kontribusi dari paper ini adalah meninjau ulang teknik-teknik dan tool utama untuk melakukan ekstrak informasi yang tersedia di Web. Secara khusus kami menekankan keuntungan-keuntungan dan kelemahan-kelemahan dari teknik-teknik serta menganalisa dari sudut pandang pengguna

Self-supervised automated wrapper generation for weblog data extraction

Data extraction from the web is notoriously hard. Of the types of resources available on the web, weblogs are becoming increasingly important due to the continued growth of the blogosphere, but remain poorly explored. Past approaches to data extraction from weblogs have often involved manual intervention and suffer from low scalability. This paper proposes a fully automated information extraction methodology based on the use of web feeds and processing of HTML. The approach includes a model for generating a wrapper that exploits web feeds for deriving a set of extraction rules automatically. Instead of performing a pairwise comparison between posts, the model matches the values of the web feeds against their corresponding HTML elements retrieved from multiple weblog posts. It adopts a probabilistic approach for deriving a set of rules and automating the process of wrapper generation. An evaluation of the model is conducted on a dataset of 2,393 posts and the results (92% accuracy) show that the proposed technique enables robust extraction of weblog properties and can be applied across the blogosphere for applications such as improved information retrieval and more robust web preservation initiatives

Web Data Extraction For Content Aggregation From E-Commerce Websites

Internetist on saanud piiramatu andmeallikas. Läbi otsingumootorite\n\ron see andmehulk tehtud kättesaadavaks igapäevasele interneti kasutajale. Sellele vaatamata on seal ikka informatsiooni, mis pole lihtsasti kättesaadav olemasolevateotsingumootoritega. See tekitab jätkuvalt vajadust ehitada aina uusi otsingumootoreid, mis esitavad informatsiooni uuel kujul, paremini kui seda on varem tehtud. Selleks, et esitada andmeid sellisel kujul, et neist tekiks lisaväärtus tuleb nad kõigepealt kokku koguda ning seejärel töödelda ja analüüsida. Antud magistritöö uurib andmete kogumise faasi selles protsessis.\n\rEsitletakse modernset andmete eraldamise süsteemi ZedBot, mis võimaldab veebilehtedel esinevad pooleldi struktureeritud andmed teisendada kõrge täpsusega struktureeritud kujule. Loodud süsteem täidab enamikku nõudeid, mida peab tänapäevane andmeeraldussüsteem täitma, milleks on: platvormist sõltumatus, võimas reeglite kirjelduse süsteem, automaatne reeglite genereerimise süsteem ja lihtsasti kasutatav kasutajaliides andmete annoteerimiseks. Eriliselt disainitud otsi-robot võimaldab andmete eraldamist kogu veebilehelt ilma inimese sekkumiseta. Töös näidatakse, et esitletud programm on sobilik andmete eraldamiseks väga suure täpsusega suurelt hulgalt veebilehtedelt ning tööriista poolt loodud andmestiku saab kasutada tooteinfo agregeerimiseks ning uue lisandväärtuse loomiseks.World Wide Web has become an unlimited source of data. Search engines have made this information available to every day Internet user. There is still information available that is not easily accessible through existing search engines, so there remains the need to create new search engines that would present information better than before. In order to present data in a way that gives extra value, it must be collected, analysed and transformed. This master thesis focuses on data collection part. Modern information extraction system ZedBot is presented, that allows extraction of highly structured data form semi structured web pages. It complies with majority of requirements set for modern data extraction system: it is platform independent, it has powerful semi automatic wrapper generation system and has easy to use user interface for annotating structured data. Specially designed web crawler allows to extraction to be performed on whole web site level without human interaction. \n\r We show that presented tool is suitable for extraction highly accurate data from large number of websites and can be used as a data source for product aggregation system to create new added value

Interactive Tuples Extraction from Semi-Structured Data

International audienceThis paper studies from a machine learning viewpoint the problem of extracting tuples of a target n-ary relation from tree structured data like XML or XHTML documents. Our system can extract, without any post-processing, tuples for all data structures including nested, rotated and cross tables. The wrapper induction algorithm we propose is based on two main ideas. It is incremental: partial tuples are extracted by increasing length. It is based on a representation-enrichment procedure: partial tuples of length i are encoded with the knowledge of extracted tu- ples of length i − 1. The algorithm is then set in a friendly interactive wrapper induction system for Web documents. We evaluate our system on several information extraction tasks over corporate Web sites. It achieves state-of-the-art results on simple data structures and succeeds on complex data structures where previous approaches fail. Experiments also show that our interactive framework significantly reduces the number of user interactions needed to build a wrapper

Implementation and Web Mounting of the WebOMiner_S Recommendation System

The ability to quickly extract information from a large amount of heterogeneous data available on the web from various Business to Consumer (B2C) or Ecommerce stores selling similar products (such as Laptops) for comparative querying and knowledge discovery remains a challenge because different web sites have different structures for their web data and web data are unstructured. For example: Find out the best and cheapest deal for Dell Laptop comparing BestBuy.ca and Amazon.com based on the following specification: Model: Inspiron 15 series, ram: 16gb, processor: i5, Hdd: 1 TB. The “WebOMiner” and “WebOMiner_S” systems perform automatic extraction by first parsing web html source code into a document object model (DOM) tree before using some pattern mining techniques to discover heterogeneous data types (e.g. text, image, links, lists) so that product schemas are extracted and stored in a back-end data warehouse for querying and recommendation. Although a web interface application of this system needs to be developed to make it accessible for to all users on the web.This thesis proposes a Web Recommendation System through Graphical User Interface, which is mounted readily on the web and is accessible to all users. It also performs integration of the web data consisting of all the product features such as Product model name, product description, market price subject to the retailer, etc. retained from the extraction process. Implementation is done using “Java server pages (JSP)” as the GUI designed in HTML, CSS, JavaScript and the framework used for this application is “Spring framework” which forms a bridge between the GUI and the data warehouse. SQL database is implemented to store the extracted product schemas for further integration, querying and knowledge discovery. All the technologies used are compatible with UNIX system for hosting the required application

A comparison of HTML-aware tools for Web Data extraction

Nowadays we live in a world where information is present everywhere in our daily life. In those last years the amount of information that we receive has grown and the stands in which is distributed have changed; from conventional newspapers or the radio to mobile phones, digital television or the Web. In this document we reference to the information that we can find in the Web, a really big source of data which is still developing