Data science has evolved far beyond science. It now represents the heart and soul of many disruptive business applications. Everywhere you look, enterprise data science practices have become industrialized within 24x7 DevOps workflows. Under that trend, automation has come to practically every process in the machine-learning DevOps pipeline that surrounds AI. Modeling is the next and perhaps ultimate milestone in the move toward end-to-end, data-science pipeline automation.

A lot of nuances of writing are lost on the internet -- things such as irony. That's why satirical material such as the writing of Andy Borowitz on the website of The New Yorker magazine has to be labeled as satire, to make sure we know. Scientists in recent years have become concerned: What about writing that isn't properly understood, such as satire mistaken for the truth, or, conversely, deliberate disinformation campaigns that are disguised as innocent satire? And so began a quest to divine some form of machine learning technology that could automatically identify satire as such and distinguish it from deliberate lies. In truth, a machine can't understand much of anything, really, and it certainly can't understand satire.

A lot of nuances of writing are lost on the internet -- things such as irony. That's why satirical material such as the writing of Andy Borowitz on the website of The New Yorker magazine has to be labeled as satire, to make sure we know. Scientists in recent years have become concerned: What about writing that isn't properly understood, such as satire mistaken for the truth, or, conversely, deliberate disinformation campaigns that are disguised as innocent satire? And so began a quest to divine some form of machine learning technology that could automatically identify satire as such and distinguish it from deliberate lies. In truth, a machine can't understand much of anything, really, and it certainly can't understand satire.

Social trading is an alternative way of trading by looking at what other traders are doing and comparing and copying their techniques and strategies. Social trading allows traders to trade online with the help of others and some have claimed shortens the learning curve from novice to experienced trader. By copying trades, traders can learn which strategies work and which do not work. Social trading is used to do speculation; in the moral context speculative practices are considered negatively and to be avoided by each individual who conversely should maintain a long term horizon avoiding any types of short term speculation. For instance, if you look at the eToro, one the biggest Social Trading Platform.

Social trading is an alternative way of trading by looking at what other traders are doing and comparing and copying their techniques and strategies. Social trading allows traders to trade online with the help of others and some have claimed shortens the learning curve from novice to experienced trader. By copying trades, traders can learn which strategies work and which do not work. Social trading is used to do speculation; in the moral context speculative practices are considered negatively and to be avoided by each individual who conversely should maintain a long term horizon avoiding any types of short term speculation. For instance, if you look at the eToro, one the biggest Social Trading Platform.

Preserving differential privacy has been well studied under centralized setting. However, it's very challenging to preserve differential privacy under multiparty setting, especially for the vertically partitioned case. In this work, we propose a new framework for differential privacy preserving multiparty learning in the vertically partitioned setting. Our core idea is based on the functional mechanism that achieves differential privacy of the released model by adding noise to the objective function. We show the server can simply dissect the objective function into single-party and cross-party sub-functions, and allocate computation and perturbation of their polynomial coefficients to local parties. Our method needs only one round of noise addition and secure aggregation. The released model in our framework achieves the same utility as applying the functional mechanism in the centralized setting. Evaluation on real-world and synthetic datasets for linear and logistic regressions shows the effectiveness of our proposed method.

The Gradient Boosting Decision Tree (GBDT) is a popular machine learning model for various tasks in recent years. In this paper, we study how to improve model accuracy of GBDT while preserving the strong guarantee of differential privacy. \textit{Sensitivity} and \textit{privacy budget} are two key design aspects for the effectiveness of differential private models. Existing solutions for GBDT with differential privacy suffer from the significant accuracy loss due to too loose sensitivity bounds and ineffective privacy budget allocations (especially across different trees in the GBDT model). Loose sensitivity bounds lead to more noise to obtain a fixed privacy level. Ineffective privacy budget allocations worsen the accuracy loss especially when the number of trees is large. Therefore, we propose a new GBDT training algorithm that achieves tighter sensitivity bounds and more effective noise allocations. Specifically, by investigating the property of gradient and the contribution of each tree in GBDTs, we propose to adaptively control the gradients of training data for each iteration and leaf node clipping in order to tighten the sensitivity bounds. Furthermore, we design a novel boosting framework to allocate the privacy budget between trees so that the accuracy loss can be reduced. Our experiments show that our approach can achieve much better model accuracy than other baselines.

The darknet markets are notorious black markets in cyberspace, which involve selling or brokering drugs, weapons, stolen credit cards, and other illicit goods. To combat illicit transactions in the cyberspace, it is important to analyze the behaviors of participants in darknet markets. Currently, many studies focus on studying the behavior of vendors. However, there is no much work on analyzing buyers. The key challenge is that the buyers are anonymized in darknet markets. For most of the darknet markets, We only observe the first and last digits of a buyer's ID, such as ``a**b''. To tackle this challenge, we propose a hidden buyer identification model, called UNMIX, which can group the transactions from one hidden buyer into one cluster given a transaction sequence from an anonymized ID. UNMIX is able to model the temporal dynamics information as well as the product, comment, and vendor information associated with each transaction. As a result, the transactions with similar patterns in terms of time and content group together as the subsequence from one hidden buyer. Experiments on the data collected from three real-world darknet markets demonstrate the effectiveness of our approach measured by various clustering metrics. Case studies on real transaction sequences explicitly show that our approach can group transactions with similar patterns into the same clusters.

In this article, we propose a novel probabilistic framework to improve the accuracy of a weighted majority voting algorithm. In order to assign higher weights to the classifiers which can correctly classify hard-to-classify instances, we introduce the Item Response Theory (IRT) framework to evaluate the samples' difficulty and classifiers' ability simultaneously. Three models are created with different assumptions suitable for different cases. When making an inference, we keep a balance between the accuracy and complexity. In our experiment, all the base models are constructed by single trees via bootstrap. To explain the models, we illustrate how the IRT ensemble model constructs the classifying boundary. We also compare their performance with other widely used methods and show that our model performs well on 19 datasets.

In this paper, we discuss the statistical properties of the $\ell_q$ optimization methods $(0