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 Inductive Learning


Bayesian Semi-supervised learning under nonparanormality

arXiv.org Machine Learning

Semi-supervised learning is a classification method which makes use of both labeled data and unlabeled data for training. In this paper, we propose a semi-supervised learning algorithm using a Bayesian semi-supervised model. We make a general assumption that the observations will follow two multivariate normal distributions depending on their true labels after the same unknown transformation. We use B-splines to put a prior on the transformation function for each component. To use unlabeled data in a semi-supervised setting, we assume the labels are missing at random. The posterior distributions can then be described using our assumptions, which we compute by the Gibbs sampling technique. The proposed method is then compared with several other available methods through an extensive simulation study. Finally we apply the proposed method in real data contexts for diagnosing breast cancer and classify radar returns. We conclude that the proposed method has better prediction accuracy in a wide variety of cases.


Supporting supervised learning in fungal Biosynthetic Gene Cluster discovery: new benchmark datasets

arXiv.org Machine Learning

Fungal Biosynthetic Gene Clusters (BGCs) of secondary metabolites are clusters of genes capable of producing natural products, compounds that play an important role in the production of a wide variety of bioactive compounds, including antibiotics and pharmaceuticals. Identifying BGCs can lead to the discovery of novel natural products to benefit human health. Previous work has been focused on developing automatic tools to support BGC discovery in plants, fungi, and bacteria. Data-driven methods, as well as probabilistic and supervised learning methods have been explored in identifying BGCs. Most methods applied to identify fungal BGCs were data-driven and presented limited scope. Supervised learning methods have been shown to perform well at identifying BGCs in bacteria, and could be well suited to perform the same task in fungi. But labeled data instances are needed to perform supervised learning. Openly accessible BGC databases contain only a very small portion of previously curated fungal BGCs. Making new fungal BGC datasets available could motivate the development of supervised learning methods for fungal BGCs and potentially improve prediction performance compared to data-driven methods. In this work we propose new publicly available fungal BGC datasets to support the BGC discovery task using supervised learning. These datasets are prepared to perform binary classification and predict candidate BGC regions in fungal genomes. In addition we analyse the performance of a well supported supervised learning tool developed to predict BGCs.


Guidelines for enhancing data locality in selected machine learning algorithms

arXiv.org Machine Learning

To deal with the complexity of the new bigger and more complex generation of data, machine learning (ML) techniques are probably the first and foremost used. For ML algorithms to produce results in a reasonable amount of time, they need to be implemented efficiently. In this paper, we analyze one of the means to increase the performances of machine learning algorithms which is exploiting data locality. Data locality and access patterns are often at the heart of performance issues in computing systems due to the use of certain hardware techniques to improve performance. Altering the access patterns to increase locality can dramatically increase performance of a given algorithm. Besides, repeated data access can be seen as redundancy in data movement. Similarly, there can also be redundancy in the repetition of calculations. This work also identifies some of the opportunities for avoiding these redundancies by directly reusing computation results. We start by motivating why and how a more efficient implementation can be achieved by exploiting reuse in the memory hierarchy of modern instruction set processors. Next we document the possibilities of such reuse in some selected machine learning algorithms. Keywords: Increasing data locality, data redundancy and reuse, machine learning, supervised learners... Notice This an extended version of the paper titled "Reviewing Data Access Patterns and Computational Redundancy for Machine Learning Algorithms" that appeared in the proceedings of the IADIS International Conference Big Data Analytics, Data Mining and Computational Intelligence 2019 (part of MCCSIS 2019)" [19] The final publication of this article is available at IOS Press through http://dx.doi.org/10.3233/IDA-184287. Because processor speed is increasing at a much faster rate than memory speed, computer architects have turned increasingly to the use of memory hierarchies with one or more levels of cache memory. This caching technique takes advantage of data locality in programs which is the property that references to the same memory location (temporal locality) or adjacent locations (spatial locality) reused within a short period of time. 1 One of the most popular ways to increase it is to rewrite the data intensive parts of the program, almost always the loops [14]. A simple example of this is to interchange the two loops in Algorithm 1 such that the code looks like Algorithm 2; note that the indices in the loop headers have changed.


A semi-supervised learning framework for quantitative structure-activity regression modelling

arXiv.org Machine Learning

Supervised learning models, also known as quantitative structure-activity regression (QSAR) models, are increasingly used in assisting the process of preclinical, small molecule drug discovery. The models are trained on data consisting of a finite dimensional representation of molecular structures and their corresponding target specific activities. These models can then be used to predict the activity of previously unmeasured novel compounds. In this work we address two problems related to this approach. The first is to estimate the extent to which the quality of the model predictions degrades for compounds very different from the compounds in the training data. The second is to adjust for the screening dependent selection bias inherent in many training data sets. In the most extreme cases, only compounds which pass an activity-dependent screening are reported. By using a semi-supervised learning framework, we show that it is possible to make predictions which take into account the similarity of the testing compounds to those in the training data and adjust for the reporting selection bias. We illustrate this approach using publicly available structure-activity data on a large set of compounds reported by GlaxoSmithKline (the Tres Cantos AntiMalarial Set) to inhibit in vitro P. falciparum growth.


Understanding AI Could Hold Up A Mirror To How We Think

#artificialintelligence

Machine learning algorithms utilizing neural networks are responsible for making many decisions in our society today. In a previous article, I discussed how AI and neural nets, despite their name, "think" in very different ways than a human would. Yet, while we have many differences, neural networks can also give us a little bit of insight into how our minds work. Supervised learning methods, methods to make a prediction based on data, are often used in machine learning algorithms. In a recent paper in Minds and Machines, David Watson of the Oxford Internet Institute and the Alan Touring Institute summarizes three ways that supervised learning methods can make predictions in similar ways to the human mind.


Classification (Supervised Learning) In Data Mining

#artificialintelligence

Each tuple/sample is assumed to belong to a predefined class, as determined by the class label attribute. Each tuple/sample is assumed to belong to a predefined class, as determined by the class label attribute. The set of tuples used for model construction: training(testing) set. The set of tuples used for model construction: training(testing) set. The model is represented as classification rules, decision trees, or statistical or mathematical formulae.


Classifying Rare Events Using Five Machine Learning Techniques

#artificialintelligence

Supervised learning is the crown jewel of Machine Learning. Supervised learning is the machine learning task or process of producing a function that predicts output variables. It has been adopted widely in the industry. For example, banks apply supervised models to detect credit card fraud. Quantitative traders make purchase decisions based on ML model predictions.


Classifying Rare Events Using Five Machine Learning Techniques

#artificialintelligence

Supervised learning is the crown jewel of Machine Learning. Supervised learning is the machine learning task or process of producing a function that predicts output variables. It has been adopted widely in the industry. For example, banks apply supervised models to detect credit card fraud. Quantitative traders make purchase decisions based on ML model predictions.


PRNet: Self-Supervised Learning for Partial-to-Partial Registration

Neural Information Processing Systems

We present a simple, flexible, and general framework titled Partial Registration Network (PRNet), for partial-to-partial point cloud registration. Inspired by recently-proposed learning-based methods for registration, we use deep networks to tackle non-convexity of the alignment and partial correspondence problem. While previous learning-based methods assume the entire shape is visible, PRNet is suitable for partial-to-partial registration, outperforming PointNetLK, DCP, and non-learning methods on synthetic data. PRNet is self-supervised, jointly learning an appropriate geometric representation, a keypoint detector that finds points in common between partial views, and keypoint-to-keypoint correspondences. We show PRNet predicts keypoints and correspondences consistently across views and objects. Furthermore, the learned representation is transferable to classification.


Reward-Conditioned Policies

arXiv.org Machine Learning

Reinforcement learning offers the promise of automating the acquisition of complex behavioral skills. However, compared to commonly used and well-understood supervised learning methods, reinforcement learning algorithms can be brittle, difficult to use and tune, and sensitive to seemingly innocuous implementation decisions. In contrast, imitation learning utilizes standard and well-understood supervised learning methods, but requires near-optimal expert data. Can we learn effective policies via supervised learning without demonstrations? The main idea that we explore in this work is that non-expert trajectories collected from sub-optimal policies can be viewed as optimal supervision, not for maximizing the reward, but for matching the reward of the given trajectory. By then conditioning the policy on the numerical value of the reward, we can obtain a policy that generalizes to larger returns. We show how such an approach can be derived as a principled method for policy search, discuss several variants, and compare the method experimentally to a variety of current reinforcement learning methods on standard benchmarks.