Unsupervised learning is a branch of machine learning that learns from test data that has not been labeled, classified or categorized. Instead of responding to feedback, unsupervised learning identifies commonalities in the data and reacts based on the presence or absence of such commonalities in each new piece of data. (Wikipedia)
Nowadays, Machine Learning and Deep Learning methods have become the state-of-the-art approach to solve data classification tasks. In order to use those methods, it is necessary to acquire and label a considerable amount of data; however, this is not straightforward in some fields, since data annotation is time consuming and might require expert knowledge. This challenge can be tackled by means of semi-supervised learning methods that take advantage of both labelled and unlabelled data. In this work, we present new semi-supervised learning methods based on techniques from Topological Data Analysis (TDA), a field that is gaining importance for analysing large amounts of data with high variety and dimensionality. In particular, we have created two semi-supervised learning methods following two different topological approaches.
Data adventure, which started with data mining concept, has been in a continuous development with introducing different algorithms. There are many applicable algorithms in AI. Besides, AI is actively used in marketing, health, agriculture, space, and autonomous vehicle production for now. Data mining is divided into different models according to fields in which it is used. These models can be grouped under four main headings as a value estimation model, database clustering model, link analysis, and difference deviations.
When it comes to machine learning, there are some broad concepts and terms that everyone in search should know. We should all know where machine learning is used, and the different types of machine learning that exist. Read on to gain a better grasp of how machine learning impacts search, what the search engines are doing and how to recognize machine learning at work. Let's start with a few definitions. Then we'll get into machine learning algorithms and models.
This story will explore how we can reason from and model graphs using labels via Supervised and Semi-Supervised Learning. I'm going to be using a MET Art Collections dataset that will build on my previous parts on Metrics, Unsupervised Learning, and more. Be sure to check out the previous story before this one to keep up on some of the pieces as I won't cover all concepts again in this one: The easiest approach to conduct Supervised Learning is to use graph measures as features in a new dataset or in addition to an existing dataset. I have seen this method yield positive results for modeling tasks, but it can be really dependent on 1. how you model as a graph (what are the inputs, outputs, edges, etc.) and 2. which metrics to use. Depending on the prediction task, we could compute node-level, edge-level, and graph-level metrics.
As the world enters a fully digital age, cyber threats are on the rise with massive data breaches, hacks into personal and financial data, and any other digital source that people can exploit. To combat these attacks, security experts are increasingly tapping into AI to stay a step ahead using every tool in their toolbox including unsupervised learning methods. Machine learning in the cybersecurity space is considered to still be in its infancy stage, but there has been a lot of traction since 2020 to have more AI involved in the process of combating cyber threats. Understanding how machine learning can be used in cyber security, recognizing the need for unsupervised learning methods in cyber security, and knowing how to implement AI in combating cyber attacks are the key to fighting cybercrime in the years ahead. The scary thing about cybercrime is that it can take up to six months to even detect a breach, and it takes an average of roughly 50 days from the time a breach is found to the time it is reported.
At a high-level, machine learning is simply the study of teaching a computer program or algorithm how to progressively improve upon a set task that it is given. On the research-side of things, machine learning can be viewed through the lens of theoretical and mathematical modeling of how this process works. However, more practically it is the study of how to build applications that exhibit this iterative improvement. There are many ways to frame this idea, but largely there are three major recognized categories: supervised learning, unsupervised learning, and reinforcement learning. In a world saturated by artificial intelligence, machine learning, and over-zealous talk about both, it is interesting to learn to understand and identify the types of machine learning we may encounter.
To begin, Supervised Learning is quite similar to learning by example. Here, we provide information to the machine and we will teach the machine. For example, we have a large collection of photographs that have been appropriately categorized as either dogs or cats. Our machine will next learn from the examples and labels provided. Perhaps our computer will discover patterns and connections between those photographs.
Classical machine learning is often categorized by how an algorithm learns to become more accurate in its predictions. The algorithm scans through data sets looking for any meaningful connection. The data that algorithms train on as well as the predictions or recommendations they output are predetermined. Data scientists may feed an algorithm mostly labeled training data, but the model is free to explore the data on its own and develop its own understanding of the data set. Data scientists program an algorithm to complete a task and give it positive or negative cues as it works out how to complete a task.
Unsupervised learning is argued to be the dark matter of human intelligence. To build in this direction, this paper focuses on unsupervised learning from an abundance of unlabeled data followed by few-shot fine-tuning on a downstream classification task. To this aim, we extend a recent study on adopting contrastive learning for self-supervised pre-training by incorporating class-level cognizance through iterative clustering and re-ranking and by expanding the contrastive optimization loss to account for it. To our knowledge, our experimentation both in standard and cross-domain scenarios demonstrate that we set a new state-of-the-art (SoTA) in (5-way, 1 and 5-shot) settings of standard mini-ImageNet benchmark as well as the (5-way, 5 and 20-shot) settings of cross-domain CDFSL benchmark. Our code and experimentation can be found in our GitHub repository: https://github.com/ojss/c3lr.