Filtration of Unwanted Messages on OSN

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1 11 Filtration of Unwanted Messages on OSN Sandip Jain Shubham Kuse Chandrakant Mahadik Ashish Lamba Komal Mahajan Professor/Information Technology/Atharva College of Engineering Abstract People nowadays exchange information with other people by exchanging it in the form of text, post, status, etc. But Today s OSN (Online Social Network) system does not provide much support to its user to provide unwanted messages which are displayed on general wall. We propose a system allowing OSN users to have a direct control on the messages posted on the walls. This will be achieved through a flexible rule-based system that allows users to customize the filtering criteria to be applied to general walls. Machine Learning based soft classifier will label messages in support of Content-based filtering along with Information Filtering and Employing Short Text Classification and Policybased Personalization. Keywords OSN, Content-based, Policy-based, Short Text Classification I. INTRODUCTION In today s modern life, almost anything done is totally based on Internet.In today s technical world social media users are increasing at a very fast rate and the student community contains the most number of users. Life without Internet cannot be imagined. Also, OSNs are just a part of modern life. From last few years people share their views, ideas, information with each other using social networking sites. Such communications may involve different types of contents like text, image, audio and video data. But, in today s OSN, there is a very high chance of posting unwanted content on particular public/private areas, called in general walls. So, to control this type of activity and prevent the unwanted messages which are written on user s wall we can implement filtering rules (FR) in our system. Also, Black List (BL) will maintain in this system.it can be used to give users the ability to automatically control the messages written on their own walls, by filtering out unwanted messages. The huge and dynamic character of these data creates the premise for the employment of web content mining strategies aimed to automatically discover useful information dormant within the data.online social networks are today one of the most popular interactive medium to communicate, share and disseminate a considerable amount of human life information. The system will be useful to all the users and communities to avail any filtered message at any time. Since no such system is there in existence till now for Mumbai University, this system will be very useful for all the users. Also any updates and changes can be done at the Administrative authority. A. Problem Statement Today s OSNs provide very little support to prevent unwanted messages on user walls. However, no content-based preferences are supported and therefore it is not possible to prevent undesired messages, such as political, vulgar, non-matter content of the user who posts them. B. Aims and Objectives The aim of the present work is therefore to propose and experimentally evaluate an automated system,

2 called Filtered Wall (FW), able to filter unwanted messages from OSN user walls. Machine Learning (ML) text categorization techniques and Content-based Preferences are automatically assigned with each short text message a set of categories based on its content. Besides classification facilities, the system provides a powerful rule layer exploiting a flexible language to specify filtering rules (FRS), by which users can state what contents, should not be displayed on their walls. In addition, the system provides the support for user-defined black lists (BLS), that is, lists of users that are temporarily prevented to post any kind of messages on a user wall and provide the spam. C. Scope Addition of notification alerts via mail is the Current scope of this system.future scope of this system is that Image Filtering Techniques. In our system we can only filter the text messages. Also based on image filtering techniques, we can have a scope of Video Filtering Techniques II. PROPOSED SCHEME We Propose an OSN architecture services considering of three-tier structure. Social Network Manager (SNM) is the first layer, which serves to provide the basic OSN functionalities; the second layer provides the support for external Social Network Applications (SNAs). For supported SNAs there is a requirement of an additional layer for their desired Graphical User Interfaces (GUIs). By considering this reference architecture our proposed system is placed in the second and third layers. To set up and manage FRs/BLs users interact with the system through GUI. The filtered wall is presented to the user through the GUI, where only authorized messages are published. There are two main components of our proposed system: Content-Based Messages Filtering (CBMF) and the Short Text Classifier (STC) modules. The function of STC is to classify messages according to a set of categories. CBMF will overlook the message filtration concept employed at this stage. III.IMPLEMENTATION PLAN A.Filtering Rules and Blacklist Techniques In defining the language for FRs specification, we consider three main issues that, in our opinion, should affect a message filtering decision. First of all, in OSNs like in everyday life, the same message may have different meanings and relevance based on who writes it. As a consequence, FRs should allow users to state constraints on message creators. Creators on which a FR applies can be selected on the basis of several different criteria; one of the most relevant is by imposing conditions on their profile s attributes. In such a way it is, for instance, possible to define rules applying only to young creators or to creators with a given religious/political view. Given the social network scenario, creators may also be identified by exploiting information on their social graph. This implies to state conditions on type, depth and trust values of the relationship(s) creators should be involved in order to apply them the specified rules. To make the system able to automatically perform these tasks, the BL mechanism has to be instructed with somerules, hereafter BL rules. In particular, these rules aim to specify (a) How the BL mechanism has to identify users to be banned and (b) For how long the banned users have to be retained in the BL, i.e., the retention time. Before going into the details of BL rules specification, it is important to note that according to our system design, these rules are not defined by the Social Network manager, which implies that these rules are not meant as general high level directives to be applied to the whole community. Rather, we decide to let the users themselves, i.e., the wall s owners to specify BL rules regulating who has to be banned from their walls. As such, the wall owner is able to clearly state how the system 12

3 has to detect users to be banned and for how long the banned users have to be retained in the BL. Note that, according to this strategy, a user might be banned from a wall, by, at the same time, being able to post in other walls. In defining the language of BL rule specification we have mainly considered the issue of how to identify users to be banned. We are aware that several strategies would be possible, which might deserve to be considered in our scenario. Among these, in this paper we have considered two main directions, postponing as future work a more exhaustive analysis of other possible strategies. In particular, our BL rules make the wall owner able to identify users to be blocked according to their profiles as well as their relationships. B. Short Text Classifier Established techniques used for text classifications work well on datasets with large documents but can suffer when the documents are short. In this context critical aspects are the definition of a set of characterizing and discriminate features allowing the representation of underlying concepts and the collection of a complete and consistent set of supervised examples. Our study is aimed at designing and evaluating various representation techniques in combination with a neural learning strategy to semantically categorizes short text. From a ML point of view, we approach the task by defining the hierarchicaltwo level strategy assuming that it is better to identify and eliminate Neutral sentences, then classify Non-Neutral sentences by the class of interest instead of doing everything in one style. This choice is motivated by related work showing advantages in classifying text and/or short text using a hierarchical strategy. The first level task is conceived as hard classification in which short text are labeled with crisp Neutral and Non-Neutral labels. The second level soft classifier acts on the crisp set of non-neutral short text and, for each of them; it simply produces estimated appropriateness or gradual membership for each of the conceived classes, without taking any hard decisions on any of them. B. 1]-Text Representation The extraction of an appropriate set of features which represents the text of a given document is acrucial task to perform in overall classification strategy. Different sets of features fortext categorization have been proposed in the literature; however the most appropriate feature types and featurerepresentation for short text messages have not been sufficiently investigated. We consider two types of features, Bag of Words (BoW) and Document properties (Dp), that are used in the experimental evaluation todetermine the combination that is most appropriate for short message classification. We introduce CF modeling information that characterizes the environment where the user is posting. These features play a key role in deterministically understanding the semantics of the messages. The underlying model for text representation is the Vector Space model (VSM) to which a text document djis represented as a vector of binary or real weights dj= W1j,..., W T j, where T is the set of terms (sometimesalso called features) that occur at least once in at least one document of the collection of document Tr, and wkj [0; 1] represents how much term tk contributes to the semantics of document dj. In the BoW representation, terms are identified with words. In the case of non-binary weighting, the weight wkj of term tk in document dj is computed according to the standard Term Frequency - Inverse Document Frequency (tf-idf) weighting function, defined as: where #(tk, dj) denotes the number of times tk occurs in dj, and #Tr(tk) denotes the document frequency of Term tk, i.e., the number of documents in Tr in which tk occurs. Domain specific criteria are adopted in choosing an additional set of features, Dp, concerning orthography, known words and statistical properties of messages. Dp features are heuristically accessed. For ex, Correct Words: it expresses the amount of terms tk TᴖK, where tk is a term of the considered document dj and K is a set of known words for the domain language. This value is normalized by Σ T k=1 #(tk,dj).and similarly for bad words, capital words, punctuations characters, exclamation marks, question marks. CFs is not very dissimilar from BoW features describing the nature of data. Therefore, all the formal definitions introduced for the BoW features also apply to CFs. 13

4 14 B. 2]-Machine Learning-based Classification We address the short text categorization as a hierarchical two-level classification process. The first level classifier performs a binary hard categorization that labels messages as Neutral and Non-Neutral. The first level filtering task facilitates the subsequent second-level task in which a finergrained classification is performed. The secondlevel classifier performs a soft-partition of Nonneutral messages assigning with a given message a gradual membership to each of the non-neutral classes. Among the variety of multi-class ML models well-suited for the text classification, we choose the Radial Basis Function Network (RBFN) model for its proven robustness in dealing with inherent vagueness in class assignments and for the experimented competitive behavior with respect to other state-of the-art classifiers. The first and second-level classifiers are then structured as regular RBFN, conceived as hard and soft classifier respectively. Its non-linear function maps the feature space to the categories space as a result of the learning phase on the given training set constituted by manually classified messages. We now formally describe the overall classification strategy. Let Ω be the set of classes to which each message can belong to. Each element of the supervised collected set of messages: D = {(mi,yi),..., (m D, y D )} is composed of the text mi and the supervised label yi {0, 1} Ω describing the belongingness to each of the defined classes. The set D is then split into two partitions, namely the training set T rsd and the test set TeSD Let M1 and M2 be the first and second level classifier respectively and y be the belongingness to the Neutral class. The learning and generalization phase works as follows: 1. Each message mi is processed such that the vector xi of features is extracted. The two sets T rsd and T esd are then transformed into T rs = {(xi, y i ),..., (x TrSD, y T rsd )} and T es = {(xi, y i ),..., (x TeSD, y T esd )} respectively. 2. A binary training set T rs1 = {(xj, y j ) T rs (xj, yj ), yj = y j1 } is created for M1. 3. A multi-class training set T rs2 = {(xj, y j ) T rs (xj, y j ), y jk = y jk+1, k = 2,..., Ω } is created for M2. 4. M1 is trained with T rs1 with the aim to recognize whether or not a message is Non-Neutral. The performance of the model M1 is then evaluated using the test set T es1. 5. M2 is trained with the Non-Neutral T rs2 messages with the aim of computing gradual membership to the Non-Neutral classes. The performance of the model M2 is then evaluated using the test set T es2. To summarizes, the hierarchical system is composed of M1 and M2, where the overall computed function, f: Rn --> R Ω is able to map the feature space to the class space, that is, to recognize the belongingness of a message to each of the Ω classes. IV.CONCLUSION Existing system is used to filter undesired messages from OSNs wall using customizable filtering rules (FR) enhancing through Black lists (BLs).The system developed GUI and a set of tools which make BLs and FRs specifications more simple and easy. The primary work of this system is to find out trust values used for OSN access control. In this system we will provide only core set of functionalities which are available in current OSNs like Facebook, Orkut, Twitter, etc. V.ACKNOWLEDGMENT It gives us great pleasure in presenting this paper report titled: Filtration of Unwanted Messages on OSN. We express our gratitude to our paper guide Prof Komal Mahajan, who provided us with all the guidance and encouragement and making the lab available to us at any time. We are eager and glad to express our gratitude to the Head of the Information Technology Dept. Prof Neelima Pathak, for her approval of this paper and much needed assistance. We would like to deeply express our sincere gratitude to our respected Principal Prof. Dr. ShrikantKallurkar and the management of Atharva College of Engineering for providing such an ideal atmosphere with well-equipped library with all the utmost necessary reference materials and up to date IT Laboratories. We are extremely thankful to all staff and the management of the college for providing us all the facilities and resources required.

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