Text Classification Based on Convolutional Neural
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Malware Classification with BERT
San Jose State University SJSU ScholarWorks Master's Projects Master's Theses and Graduate Research Spring 5-25-2021 Malware Classification with BERT Joel Lawrence Alvares Follow this and additional works at: https://scholarworks.sjsu.edu/etd_projects Part of the Artificial Intelligence and Robotics Commons, and the Information Security Commons Malware Classification with Word Embeddings Generated by BERT and Word2Vec Malware Classification with BERT Presented to Department of Computer Science San José State University In Partial Fulfillment of the Requirements for the Degree By Joel Alvares May 2021 Malware Classification with Word Embeddings Generated by BERT and Word2Vec The Designated Project Committee Approves the Project Titled Malware Classification with BERT by Joel Lawrence Alvares APPROVED FOR THE DEPARTMENT OF COMPUTER SCIENCE San Jose State University May 2021 Prof. Fabio Di Troia Department of Computer Science Prof. William Andreopoulos Department of Computer Science Prof. Katerina Potika Department of Computer Science 1 Malware Classification with Word Embeddings Generated by BERT and Word2Vec ABSTRACT Malware Classification is used to distinguish unique types of malware from each other. This project aims to carry out malware classification using word embeddings which are used in Natural Language Processing (NLP) to identify and evaluate the relationship between words of a sentence. Word embeddings generated by BERT and Word2Vec for malware samples to carry out multi-class classification. BERT is a transformer based pre- trained natural language processing (NLP) model which can be used for a wide range of tasks such as question answering, paraphrase generation and next sentence prediction. However, the attention mechanism of a pre-trained BERT model can also be used in malware classification by capturing information about relation between each opcode and every other opcode belonging to a malware family. -
Automatic Correction of Real-Word Errors in Spanish Clinical Texts
sensors Article Automatic Correction of Real-Word Errors in Spanish Clinical Texts Daniel Bravo-Candel 1,Jésica López-Hernández 1, José Antonio García-Díaz 1 , Fernando Molina-Molina 2 and Francisco García-Sánchez 1,* 1 Department of Informatics and Systems, Faculty of Computer Science, Campus de Espinardo, University of Murcia, 30100 Murcia, Spain; [email protected] (D.B.-C.); [email protected] (J.L.-H.); [email protected] (J.A.G.-D.) 2 VÓCALI Sistemas Inteligentes S.L., 30100 Murcia, Spain; [email protected] * Correspondence: [email protected]; Tel.: +34-86888-8107 Abstract: Real-word errors are characterized by being actual terms in the dictionary. By providing context, real-word errors are detected. Traditional methods to detect and correct such errors are mostly based on counting the frequency of short word sequences in a corpus. Then, the probability of a word being a real-word error is computed. On the other hand, state-of-the-art approaches make use of deep learning models to learn context by extracting semantic features from text. In this work, a deep learning model were implemented for correcting real-word errors in clinical text. Specifically, a Seq2seq Neural Machine Translation Model mapped erroneous sentences to correct them. For that, different types of error were generated in correct sentences by using rules. Different Seq2seq models were trained and evaluated on two corpora: the Wikicorpus and a collection of three clinical datasets. The medicine corpus was much smaller than the Wikicorpus due to privacy issues when dealing Citation: Bravo-Candel, D.; López-Hernández, J.; García-Díaz, with patient information. -
ACL 2019 Social Media Mining for Health Applications (#SMM4H)
ACL 2019 Social Media Mining for Health Applications (#SMM4H) Workshop & Shared Task Proceedings of the Fourth Workshop August 2, 2019 Florence, Italy c 2019 The Association for Computational Linguistics Order copies of this and other ACL proceedings from: Association for Computational Linguistics (ACL) 209 N. Eighth Street Stroudsburg, PA 18360 USA Tel: +1-570-476-8006 Fax: +1-570-476-0860 [email protected] ISBN 978-1-950737-46-8 ii Preface Welcome to the 4th Social Media Mining for Health Applications Workshop and Shared Task - #SMM4H 2019. The total number of users of social media continues to grow worldwide, resulting in the generation of vast amounts of data. Popular social networking sites such as Facebook, Twitter and Instagram dominate this sphere. According to estimates, 500 million tweets and 4.3 billion Facebook messages are posted every day 1. The latest Pew Research Report 2, nearly half of adults worldwide and two- thirds of all American adults (65%) use social networking. The report states that of the total users, 26% have discussed health information, and, of those, 30% changed behavior based on this information and 42% discussed current medical conditions. Advances in automated data processing, machine learning and NLP present the possibility of utilizing this massive data source for biomedical and public health applications, if researchers address the methodological challenges unique to this media. In its fourth iteration, the #SMM4H workshop takes place in Florence, Italy, on August 2, 2019, and is co-located with the -
Mapping the Hyponymy Relation of Wordnet Onto
Under review as a conference paper at ICLR 2019 MAPPING THE HYPONYMY RELATION OF WORDNET ONTO VECTOR SPACES Anonymous authors Paper under double-blind review ABSTRACT In this paper, we investigate mapping the hyponymy relation of WORDNET to feature vectors. We aim to model lexical knowledge in such a way that it can be used as input in generic machine-learning models, such as phrase entailment predictors. We propose two models. The first one leverages an existing mapping of words to feature vectors (fastText), and attempts to classify such vectors as within or outside of each class. The second model is fully supervised, using solely WORDNET as a ground truth. It maps each concept to an interval or a disjunction thereof. On the first model, we approach, but not quite attain state of the art performance. The second model can achieve near-perfect accuracy. 1 INTRODUCTION Distributional encoding of word meanings from the large corpora (Mikolov et al., 2013; 2018; Pen- nington et al., 2014) have been found to be useful for a number of NLP tasks. These approaches are based on a probabilistic language model by Bengio et al. (2003) of word sequences, where each word w is represented as a feature vector f(w) (a compact representation of a word, as a vector of floating point values). This means that one learns word representations (vectors) and probabilities of word sequences at the same time. While the major goal of distributional approaches is to identify distributional patterns of words and word sequences, they have even found use in tasks that require modeling more fine-grained relations between words than co-occurrence in word sequences. -
Pairwise Fasttext Classifier for Entity Disambiguation
Pairwise FastText Classifier for Entity Disambiguation a,b b b Cheng Yu , Bing Chu , Rohit Ram , James Aichingerb, Lizhen Qub,c, Hanna Suominenb,c a Project Cleopatra, Canberra, Australia b The Australian National University c DATA 61, Australia [email protected] {u5470909,u5568718,u5016706, Hanna.Suominen}@anu.edu.au [email protected] deterministically. Then we will evaluate PFC’s Abstract performance against a few baseline methods, in- cluding SVC3 with hand-crafted text features. Fi- For the Australasian Language Technology nally, we will discuss ways to improve disambig- Association (ALTA) 2016 Shared Task, we uation performance using PFC. devised Pairwise FastText Classifier (PFC), an efficient embedding-based text classifier, 2 Pairwise Fast-Text Classifier (PFC) and used it for entity disambiguation. Com- pared with a few baseline algorithms, PFC Our Pairwise FastText Classifier is inspired by achieved a higher F1 score at 0.72 (under the the FastText. Thus this section starts with a brief team name BCJR). To generalise the model, description of FastText, and proceeds to demon- we also created a method to bootstrap the strate PFC. training set deterministically without human labelling and at no financial cost. By releasing 2.1 FastText PFC and the dataset augmentation software to the public1, we hope to invite more collabora- FastText maps each vocabulary to a real-valued tion. vector, with unknown words having a special vo- cabulary ID. A document can be represented as 1 Introduction the average of all these vectors. Then FastText will train a maximum entropy multi-class classi- The goal of the ALTA 2016 Shared Task was to fier on the vectors and the output labels. -
Learned in Speech Recognition: Contextual Acoustic Word Embeddings
LEARNED IN SPEECH RECOGNITION: CONTEXTUAL ACOUSTIC WORD EMBEDDINGS Shruti Palaskar∗, Vikas Raunak∗ and Florian Metze Carnegie Mellon University, Pittsburgh, PA, U.S.A. fspalaska j vraunak j fmetze [email protected] ABSTRACT model [10, 11, 12] trained for direct Acoustic-to-Word (A2W) speech recognition [13]. Using this model, we jointly learn to End-to-end acoustic-to-word speech recognition models have re- automatically segment and classify input speech into individual cently gained popularity because they are easy to train, scale well to words, hence getting rid of the problem of chunking or requiring large amounts of training data, and do not require a lexicon. In addi- pre-defined word boundaries. As our A2W model is trained at the tion, word models may also be easier to integrate with downstream utterance level, we show that we can not only learn acoustic word tasks such as spoken language understanding, because inference embeddings, but also learn them in the proper context of their con- (search) is much simplified compared to phoneme, character or any taining sentence. We also evaluate our contextual acoustic word other sort of sub-word units. In this paper, we describe methods embeddings on a spoken language understanding task, demonstrat- to construct contextual acoustic word embeddings directly from a ing that they can be useful in non-transcription downstream tasks. supervised sequence-to-sequence acoustic-to-word speech recog- Our main contributions in this paper are the following: nition model using the learned attention distribution. On a suite 1. We demonstrate the usability of attention not only for aligning of 16 standard sentence evaluation tasks, our embeddings show words to acoustic frames without any forced alignment but also for competitive performance against a word2vec model trained on the constructing Contextual Acoustic Word Embeddings (CAWE). -
Fasttext.Zip: Compressing Text Classification Models
Under review as a conference paper at ICLR 2017 FASTTEXT.ZIP: COMPRESSING TEXT CLASSIFICATION MODELS Armand Joulin, Edouard Grave, Piotr Bojanowski, Matthijs Douze, Herve´ Jegou´ & Tomas Mikolov Facebook AI Research fajoulin,egrave,bojanowski,matthijs,rvj,[email protected] ABSTRACT We consider the problem of producing compact architectures for text classifica- tion, such that the full model fits in a limited amount of memory. After consid- ering different solutions inspired by the hashing literature, we propose a method built upon product quantization to store word embeddings. While the original technique leads to a loss in accuracy, we adapt this method to circumvent quan- tization artefacts. Combined with simple approaches specifically adapted to text classification, our approach derived from fastText requires, at test time, only a fraction of the memory compared to the original FastText, without noticeably sacrificing quality in terms of classification accuracy. Our experiments carried out on several benchmarks show that our approach typically requires two orders of magnitude less memory than fastText while being only slightly inferior with respect to accuracy. As a result, it outperforms the state of the art by a good margin in terms of the compromise between memory usage and accuracy. 1 INTRODUCTION Text classification is an important problem in Natural Language Processing (NLP). Real world use- cases include spam filtering or e-mail categorization. It is a core component in more complex sys- tems such as search and ranking. Recently, deep learning techniques based on neural networks have achieved state of the art results in various NLP applications. One of the main successes of deep learning is due to the effectiveness of recurrent networks for language modeling and their application to speech recognition and machine translation (Mikolov, 2012). -
Question Embeddings for Semantic Answer Type Prediction
Question Embeddings for Semantic Answer Type Prediction Eleanor Bill1 and Ernesto Jiménez-Ruiz2 1, 2 City, University of London, London, EC1V 0HB Abstract. This paper considers an answer type and category prediction challenge for a set of natural language questions, and proposes a question answering clas- sification system based on word and DBpedia knowledge graph embeddings. The questions are parsed for keywords, nouns and noun phrases before word and knowledge graph embeddings are applied to the parts of the question. The vectors produced are used to train multiple multi-layer perceptron models, one for each answer type in a multiclass one-vs-all classification system for both answer cat- egory prediction and answer type prediction. Different combinations of vectors and the effect of creating additional positive and negative training samples are evaluated in order to find the best classification system. The classification system that predict the answer category with highest accuracy are the classifiers trained on knowledge graph embedded noun phrases vectors from the original training data, with an accuracy of 0.793. The vector combination that produces the highest NDCG values for answer category accuracy is the word embeddings from the parsed question keyword and nouns parsed from the original training data, with NDCG@5 and NDCG@10 values of 0.471 and 0.440 respectively for the top five and ten predicted answer types. Keywords: Semantic Web, knowledge graph embedding, answer type predic- tion, question answering. 1 Introduction 1.1 The SMART challenge The challenge [1] provided a training set of natural language questions alongside a sin- gle given answer category (Boolean, literal or resource) and 1-6 given answer types. -
Lecture 26 Word Embeddings and Recurrent Nets
CS447: Natural Language Processing http://courses.engr.illinois.edu/cs447 Where we’re at Lecture 25: Word Embeddings and neural LMs Lecture 26: Recurrent networks Lecture 26 Lecture 27: Sequence labeling and Seq2Seq Lecture 28: Review for the final exam Word Embeddings and Lecture 29: In-class final exam Recurrent Nets Julia Hockenmaier [email protected] 3324 Siebel Center CS447: Natural Language Processing (J. Hockenmaier) !2 What are neural nets? Simplest variant: single-layer feedforward net For binary Output unit: scalar y classification tasks: Single output unit Input layer: vector x Return 1 if y > 0.5 Recap Return 0 otherwise For multiclass Output layer: vector y classification tasks: K output units (a vector) Input layer: vector x Each output unit " yi = class i Return argmaxi(yi) CS447: Natural Language Processing (J. Hockenmaier) !3 CS447: Natural Language Processing (J. Hockenmaier) !4 Multi-layer feedforward networks Multiclass models: softmax(yi) We can generalize this to multi-layer feedforward nets Multiclass classification = predict one of K classes. Return the class i with the highest score: argmaxi(yi) Output layer: vector y In neural networks, this is typically done by using the softmax N Hidden layer: vector hn function, which maps real-valued vectors in R into a distribution … … … over the N outputs … … … … … …. For a vector z = (z0…zK): P(i) = softmax(zi) = exp(zi) ∕ ∑k=0..K exp(zk) Hidden layer: vector h1 (NB: This is just logistic regression) Input layer: vector x CS447: Natural Language Processing (J. Hockenmaier) !5 CS447: Natural Language Processing (J. Hockenmaier) !6 Neural Language Models LMs define a distribution over strings: P(w1….wk) LMs factor P(w1….wk) into the probability of each word: " P(w1….wk) = P(w1)·P(w2|w1)·P(w3|w1w2)·…· P(wk | w1….wk#1) A neural LM needs to define a distribution over the V words in Neural Language the vocabulary, conditioned on the preceding words. -
Arxiv:2007.00183V2 [Eess.AS] 24 Nov 2020
WHOLE-WORD SEGMENTAL SPEECH RECOGNITION WITH ACOUSTIC WORD EMBEDDINGS Bowen Shi, Shane Settle, Karen Livescu TTI-Chicago, USA fbshi,settle.shane,[email protected] ABSTRACT Segmental models are sequence prediction models in which scores of hypotheses are based on entire variable-length seg- ments of frames. We consider segmental models for whole- word (“acoustic-to-word”) speech recognition, with the feature vectors defined using vector embeddings of segments. Such models are computationally challenging as the number of paths is proportional to the vocabulary size, which can be orders of magnitude larger than when using subword units like phones. We describe an efficient approach for end-to-end whole-word segmental models, with forward-backward and Viterbi de- coding performed on a GPU and a simple segment scoring function that reduces space complexity. In addition, we inves- tigate the use of pre-training via jointly trained acoustic word embeddings (AWEs) and acoustically grounded word embed- dings (AGWEs) of written word labels. We find that word error rate can be reduced by a large margin by pre-training the acoustic segment representation with AWEs, and additional Fig. 1. Whole-word segmental model for speech recognition. (smaller) gains can be obtained by pre-training the word pre- Note: boundary frames are not shared. diction layer with AGWEs. Our final models improve over segmental models, where the sequence probability is com- prior A2W models. puted based on segment scores instead of frame probabilities. Index Terms— speech recognition, segmental model, Segmental models have a long history in speech recognition acoustic-to-word, acoustic word embeddings, pre-training research, but they have been used primarily for phonetic recog- nition or as phone-level acoustic models [11–18]. -
Data Driven Value Creation
DATA DRIVEN VALUE CREATION DATA SCIENCE & ANALYTICS | DATA MANAGEMENT | VISUALIZATION & DATA EXPERIENCE D ONE, Sihlfeldstrasse 58, 8003 Zürich, d-one.ai Agenda Time Content Who 9.00 Introduction Philipp 9.30 Hands-On 1: How to kick-start NLP Jacqueline 10.15 Break / Letting People Catch up All ;-) 10.45 About ELK Philipp 11.00 Hands-On 2: Deep Dive Jacqueline 12.15 Wrap up / Discussion All 2 Today’s hosts Philipp Thomann Jacqueline Stählin Here today & tomorrow morning Here today & Monday till Wednesday 3 Setup Course Git - https://github.com/d-one/NLPeasy-workshop For infos during Workshop - https://tlk.io/amld2020-nlpeasy 4 «Making sense of data is the winning competence in all industries.» 5 Data drives Transformation 6 About ■ Zurich-based, established in 2005 with focus: data-driven value creation ■ 50 data professionals with excellent business and technical understanding & network ■ International & Swiss clients ■ In selected cases: investor for data-driven start-ups 7 Capabilities Business Consulting - Guide on data journey - Use cases, roadmap - Transformation and change - Building capabilities Machine Learning / AI Data Architecture - Ideation, implementation, - Data strategy operationalization Passionate - Enterprise requirements - Algorithms, modelling, NLP & - Information factory - Image recognition, visual analytics Down to - BI and analytics - Text analytics - Data science laboratory earth Data Management Data Experience - Data supply chain - From data to Insights to action - Data integration and modelling - Business report -
Two Models for Named Entity Recognition in Spanish
Two Models for Named Entity Recognition in Spanish. Submission to the CAPITEL Shared Task at IberLEF 2020 Elena Álvarez-Melladoa aInformation Sciences Institute, University of Southern California Abstract This paper documents two sequence-labeling models for NER in Spanish: a conditional random field model with handcrafted features and a BiLSTM-CRF model with word and character embeddings. Both models were trained and tested using CAPITEL (an annotated corpus of newswire written in European Spanish) and were submitted to the shared task on Spanish NER at IberLEF 2020. The best result was obtained by the CRF model, which produced an F1 score of 84.39 on the test set and was ranked #6 on the shared task. Keywords Spanish NER, CRF, BiLSTM-CRF 1. Introduction and Previous Work Named entity recognition (NER) is the task of extracting relevant spans of text (such as person names, location names, organization names) from a given document. NER has usually been framed as a sequence labeling problem [1]. Consequently, different sequence labeling approaches have been applied to NER, such as hidden Markov models [2], maxent Markov models [3] or conditional random field [4, 5]. More recently, different neural architectures have also been applied to NER [6, 7]. In this paper, we explore two sequence-labeling models to perform NER on CAPITEL, an annotated corpus of journalistic texts written in European Spanish. The explored models are a CRF model with handcrafted features and a BiLSTM-CRF model with word and character embeddings. Both models were submitted to the CAPITEL shared task on Spanish NER at IberLEF 2020 [8].