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Finding Representative Group Fairness Metrics Using Correlation Estimations

arXiv.org Artificial Intelligence

It is of critical importance to be aware of the historical discrimination embedded in the data and to consider a fairness measure to reduce bias throughout the predictive modeling pipeline. Given various notions of fairness defined in the literature, investigating the correlation and interaction among metrics is vital for addressing unfairness. Practitioners and data scientists should be able to comprehend each metric and examine their impact on one another given the context, use case, and regulations. Exploring the combinatorial space of different metrics for such examination is burdensome. To alleviate the burden of selecting fairness notions for consideration, we propose a framework that estimates the correlation among fairness notions. Our framework consequently identifies a set of diverse and semantically distinct metrics as representative for a given context. We propose a Monte-Carlo sampling technique for computing the correlations between fairness metrics by indirect and efficient perturbation in the model space. Using the estimated correlations, we then find a subset of representative metrics. The paper proposes a generic method that can be generalized to any arbitrary set of fairness metrics. We showcase the validity of the proposal using comprehensive experiments on real-world benchmark datasets.


Data-Driven Revision of Conditional Norms in Multi-Agent Systems

Journal of Artificial Intelligence Research

In multi-agent systems, norm enforcement is a mechanism for steering the behavior of individual agents in order to achieve desired system-level objectives. Due to the dynamics of multi-agent systems, however, it is hard to design norms that guarantee the achievement of the objectives in every operating context. Also, these objectives may change over time, thereby making previously defined norms ineffective. In this paper, we investigate the use of system execution data to automatically synthesise and revise conditional prohibitions with deadlines, a type of norms aimed at prohibiting agents from exhibiting certain patterns of behaviors. We propose DDNR (Data-Driven Norm Revision), a data-driven approach to norm revision that synthesises revised norms with respect to a data set of traces describing the behavior of the agents in the system. We evaluate DDNR using a state-of-the-art, off-the-shelf urban traffic simulator. The results show that DDNR synthesises revised norms that are significantly more accurate than the original norms in distinguishing adequate and inadequate behaviors for the achievement of the system-level objectives.


Twitter Artificial Intelligence

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How does Twitter use artificial intelligence and machine learning? Twitter uses large-scale machine learning and AI for sentiment analysis, bot analysis and detection of fake accounts, image classification and more. From Amazon to Instagram, Sephora, Microsoft, and Twitter, AI will shape the future of speech in America and beyond. The big question is not if they use it, but how it is being used, and what impact will this have on consumer privacy in the future. For the past fifteen years, I have been a national commentator on the politics of big tech and social media platforms. Social Media content decisions have become highly political, and artificial intelligence has proliferated this process at scale. But somewhere along the way, the public was left in the dark on just how large of a role machine learning plays in large-scale content operations in Silicon Valley. While the national conversation on free speech focuses on high-profile executives of tech companies and how content ...


Countering Malicious Content Moderation Evasion in Online Social Networks: Simulation and Detection of Word Camouflage

arXiv.org Artificial Intelligence

Content moderation is the process of screening and monitoring user-generated content online. It plays a crucial role in stopping content resulting from unacceptable behaviors such as hate speech, harassment, violence against specific groups, terrorism, racism, xenophobia, homophobia, or misogyny, to mention some few, in Online Social Platforms. These platforms make use of a plethora of tools to detect and manage malicious information; however, malicious actors also improve their skills, developing strategies to surpass these barriers and continuing to spread misleading information. Twisting and camouflaging keywords are among the most used techniques to evade platform content moderation systems. In response to this recent ongoing issue, this paper presents an innovative approach to address this linguistic trend in social networks through the simulation of different content evasion techniques and a multilingual Transformer model for content evasion detection. In this way, we share with the rest of the scientific community a multilingual public tool, named "pyleetspeak" to generate/simulate in a customizable way the phenomenon of content evasion through automatic word camouflage and a multilingual Named-Entity Recognition (NER) Transformer-based model tuned for its recognition and detection. The multilingual NER model is evaluated in different textual scenarios, detecting different types and mixtures of camouflage techniques, achieving an overall weighted F1 score of 0.8795. This article contributes significantly to countering malicious information by developing multilingual tools to simulate and detect new methods of evasion of content on social networks, making the fight against information disorders more effective.


A Robust Cybersecurity Topic Classification Tool

arXiv.org Artificial Intelligence

Identifying cybersecurity discussions in open forums at scale is a topic of great interest for the purpose of mitigating and understanding modern cyber threats [1-3]. The challenge is that these discussions are typically quite noisy (i.e., they contain community known synonyms or acronyms or slang) and it is difficult to get labelled data in order to train resilient NLP (natural language processing) topic classifiers. Additionally, it is important that a tool that detects cybersecurity discussions in internet text sources is scalable and offers low errors rates (in particular, both low false negative rates and low false positive rates). In order to address the challenges of finding relevant cybersecurity labelled data, we use a technique that gathers posts or articles from different internet sources that have user defined topic labels. We then collect and label the training text as being cybersecurity related or not based on the subset of labels that the text source offers.


Semi-supervised multiscale dual-encoding method for faulty traffic data detection

arXiv.org Artificial Intelligence

Inspired by the recent success of deep learning in multiscale information encoding, we introduce a variational autoencoder (VAE) based semi-supervised method for detection of faulty traffic data, which is cast as a classification problem. Continuous wavelet transform (CWT) is applied to the time series of traffic volume data to obtain rich features embodied in time-frequency representation, followed by a twin of VAE models to separately encode normal data and faulty data. The resulting multiscale dual encodings are concatenated and fed to an attention-based classifier, consisting of a self-attention module and a multilayer perceptron. For comparison, the proposed architecture is evaluated against five different encoding schemes, including (1) VAE with only normal data encoding, (2) VAE with only faulty data encoding, (3) VAE with both normal and faulty data encodings, but without attention module in the classifier, (4) siamese encoding, and (5) cross-vision transformer (CViT) encoding. The first four encoding schemes adopted the same convolutional neural network (CNN) architecture while the fifth encoding scheme follows the transformer architecture of CViT. Our experiments show that the proposed architecture with the dual encoding scheme, coupled with attention module, outperforms other encoding schemes and results in classification accuracy of 96.4%, precision of 95.5%, and recall of 97.7%.


Confusion Matrices and Accuracy Statistics for Binary Classifiers Using Unlabeled Data: The Diagnostic Test Approach

arXiv.org Artificial Intelligence

Sometimes it is important to know the accuracy of a classifier on unlabeled data. The labels may be delayed, as in consumer purchasing predictions, or obtaining the labels is cost prohibitive. The labels may not exist, as for some medical conditions, for which the true gold standard diagnostic test(a 100% sensitive and 100% specific classifier) would require subjects be euthanized and autopsied to obtain labels. Epidemiologists and biostatisticians have developed statistical methods for assessing the sensitivity (Se) and specificity (Sp) of diagnostic tests when gold standard comparison tests are unavailable. In data science terms, the diagnostic test assessment data are unlabeled. In this article, I describe how to modify those diagnostic test statistical methods to estimate confusion matrices and accuracy statistics for binary classifiers.


12 Best Online Courses for Machine Learning with Python- 2023

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Python is one of the most widely used programming languages in the Machine Learning field. Python has many packages and libraries that are specifically tailored for certain functions, including pandas, NumPy, scikit-learn, Matplotlib, and SciPy. So if you want to learn Machine Learning with Python, this article is for you. In this article, you will find the 12 Best Online Courses for Machine Learning with Python. Now, without wasting your time, let's start finding the Best Online Courses for Machine Learning with Python.


Unlock the Power of the Confusion Matrix

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A confusion matrix is a tool commonly used in the field of machine learning to evaluate the performance of a classification model. It is a table that summarizes the predictions made by a model and compares them to the true outcomes. In this blog, we will delve into the concept of the confusion matrix and its various components, as well as how to interpret and use it to evaluate the performance of a model. So, a confusion matrix is a useful tool to understand the performance of a classification model, and it can help us in improving the model if needed. The confusion matrix is a table that contains four different types of predictions made by a classification model: true positives (TP), false positives (FP), true negatives (TN), and false negatives (FN). Understanding these four types of predictions is crucial in interpreting the results of a confusion matrix.


GWO-FI: A novel machine learning framework by combining Gray Wolf Optimizer and Frequent Itemsets to diagnose and investigate effective factors on In-Hospital Mortality and Length of Stay among Kermanshahian Cardiovascular Disease patients

arXiv.org Artificial Intelligence

Investigation and analysis of patient outcomes, including in-hospital mortality and length of stay, are crucial for assisting clinicians in determining a patient's result at the outset of their hospitalization and for assisting hospitals in allocating their resources. This paper proposes an approach based on combining the well-known gray wolf algorithm with frequent items extracted by association rule mining algorithms. First, original features are combined with the discriminative extracted frequent items. The best subset of these features is then chosen, and the parameters of the used classification algorithms are also adjusted, using the gray wolf algorithm. This framework was evaluated using a real dataset made up of 2816 patients from the Imam Ali Kermanshah Hospital in Iran. The study's findings indicate that low Ejection Fraction, old age, high CPK values, and high Creatinine levels are the main contributors to patients' mortality. Several significant and interesting rules related to mortality in hospitals and length of stay have also been extracted and presented. Additionally, the accuracy, sensitivity, specificity, and auroc of the proposed framework for the diagnosis of mortality in the hospital using the SVM classifier were 0.9961, 0.9477, 0.9992, and 0.9734, respectively. According to the framework's findings, adding frequent items as features considerably improves classification accuracy.