How do machine learning professionals make data readable and accessible? What techniques do they use to dissect raw information?
One of these techniques is clustering. Data clustering is the process of grouping items in a data set together. These items are related, allowing key stakeholders to make critical strategic decisions using the insights.
After preparing data, which is what specialists do 50%-80% of the time, clustering takes center stage. It forms structures other members of the company can understand more easily, even if they lack advanced technical knowledge.
Clustering in machine learning involves many techniques to help accomplish this goal. Here is a detailed overview of those techniques.
Clustering Techniques
Data science is an ever-changing field with lots of variables and fluctuations. However, one thing’s for sure – whether you want to practice clustering in data mining or clustering in machine learning, you can use a wide array of tools to automate your efforts.
Partitioning Methods
The first groups of techniques are the so-called partitioning methods. There are three main sub-types of this model.
K-Means Clustering
K-means clustering is an effective yet straightforward clustering system. To execute this technique, you need to assign clusters in your data sets. From there, define your number K, which tells the program how many centroids (“coordinates” representing the center of your clusters) you need. The machine then recognizes your K and categorizes data points to nearby clusters.
You can look at K-means clustering like finding the center of a triangle. Zeroing in on the center lets you divide the triangle into several areas, allowing you to make additional calculations.
And the name K-means clustering is pretty self-explanatory. It refers to finding the median value of your clusters – centroids.
K-Medoids Clustering
K-means clustering is useful but is prone to so-called “outlier data.” This information is different from other data points and can merge with others. Data miners need a reliable way to deal with this issue.
Enter K-medoids clustering.
It’s similar to K-means clustering, but just like planes overcome gravity, so does K-medoids clustering overcome outliers. It utilizes “medoids” as the reference points – which contain maximum similarities with other data points in your cluster. As a result, no outliers interfere with relevant data points, making this one of the most dependable clustering techniques in data mining.
Fuzzy C-Means Clustering
Fuzzy C-means clustering is all about calculating the distance from the median point to individual data points. If a data point is near the cluster centroid, it’s relevant to the goal you want to accomplish with your data mining. The farther you go from this point, the farther you move the goalpost and decrease relevance.
Hierarchical Methods
Some forms of clustering in machine learning are like textbooks – similar topics are grouped in a chapter and are different from topics in other chapters. That’s precisely what hierarchical clustering aims to accomplish. You can the following methods to create data hierarchies.
Agglomerative Clustering
Agglomerative clustering is one of the simplest forms of hierarchical clustering. It divides your data set into several clusters, making sure data points are similar to other points in the same cluster. By grouping them, you can see the differences between individual clusters.
Before the execution, each data point is a full-fledged cluster. The technique helps you form more clusters, making this a bottom-up strategy.
Divisive Clustering
Divisive clustering lies on the other end of the hierarchical spectrum. Here, you start with just one cluster and create more as you move through your data set. This top-down approach produces as many clusters as necessary until you achieve the requested number of partitions.
Density-Based Methods
Birds of a feather flock together. That’s the basic premise of density-based methods. Data points that are close to each other form high-density clusters, indicating their cohesiveness. The two primary density-based methods of clustering in data mining are DBSCAN and OPTICS.
DBSCAN (Density-Based Spatial Clustering of Applications With Noise)
Related data groups are close to each other, forming high-density areas in your data sets. The DBSCAN method picks up on these areas and groups information accordingly.
OPTICS (Ordering Points to Identify the Clustering Structure)
The OPTICS technique is like DBSCAN, grouping data points according to their density. The only major difference is that OPTICS can identify varying densities in larger groups.
Grid-Based Methods
You can see grids on practically every corner. They can easily be found in your house or your car. They’re also prevalent in clustering.
STING (Statistical Information Grid)
The STING grid method divides a data point into rectangular grills. Afterward, you determine certain parameters for your cells to categorize information.
CLIQUE (Clustering in QUEst)
Agglomerative clustering isn’t the only bottom-up clustering method on our list. There’s also the CLIQUE technique. It detects clusters in your environment and combines them according to your parameters.
Model-Based Methods
Different clustering techniques have different assumptions. The assumption of model-based methods is that a model generates specific data points. Several such models are used here.
Gaussian Mixture Models (GMM)
The aim of Gaussian mixture models is to identify so-called Gaussian distributions. Each distribution is a cluster, and any information within a distribution is related.
Hidden Markov Models (HMM)
Most people use HMM to determine the probability of certain outcomes. Once they calculate the probability, they can figure out the distance between individual data points for clustering purposes.
Spectral Clustering
If you often deal with information organized in graphs, spectral clustering can be your best friend. It finds related groups of notes according to linked edges.
Comparison of Clustering Techniques
It’s hard to say that one algorithm is superior to another because each has a specific purpose. Nevertheless, some clustering techniques might be especially useful in particular contexts:
- OPTICS beats DBSCAN when clustering data points with different densities.
- K-means outperforms divisive clustering when you wish to reduce the distance between a data point and a cluster.
- Spectral clustering is easier to implement than the STING and CLIQUE methods.
Cluster Analysis
You can’t put your feet up after clustering information. The next step is to analyze the groups to extract meaningful information.
Importance of Cluster Analysis in Data Mining
The importance of clustering in data mining can be compared to the importance of sunlight in tree growth. You can’t get valuable insights without analyzing your clusters. In turn, stakeholders wouldn’t be able to make critical decisions about improving their marketing efforts, target audience, and other key aspects.
Steps in Cluster Analysis
Just like the production of cars consists of many steps (e.g., assembling the engine, making the chassis, painting, etc.), cluster analysis is a multi-stage process:
Data Preprocessing
Noise and other issues plague raw information. Data preprocessing solves this issue by making data more understandable.
Feature Selection
You zero in on specific features of a cluster to identify those clusters more easily. Plus, feature selection allows you to store information in a smaller space.
Clustering Algorithm Selection
Choosing the right clustering algorithm is critical. You need to ensure your algorithm is compatible with the end result you wish to achieve. The best way to do so is to determine how you want to establish the relatedness of the information (e.g., determining median distances or densities).
Cluster Validation
In addition to making your data points easily digestible, you also need to verify whether your clustering process is legit. That’s where cluster validation comes in.
Cluster Validation Techniques
There are three main cluster validation techniques when performing clustering in machine learning:
Internal Validation
Internal validation evaluates your clustering based on internal information.
External Validation
External validation assesses a clustering process by referencing external data.
Relative Validation
You can vary your number of clusters or other parameters to evaluate your clustering. This procedure is known as relative validation.
Applications of Clustering in Data Mining
Clustering may sound a bit abstract, but it has numerous applications in data mining.
- Customer Segmentation – This is the most obvious application of clustering. You can group customers according to different factors, like age and interests, for better targeting.
- Anomaly Detection – Detecting anomalies or outliers is essential for many industries, such as healthcare.
- Image Segmentation – You use data clustering if you want to recognize a certain object in an image.
- Document Clustering – Organizing documents is effortless with document clustering.
- Bioinformatics and Gene Expression Analysis – Grouping related genes together is relatively simple with data clustering.
Challenges and Future Directions
- Scalability – One of the biggest challenges of data clustering is expected to be applying the process to larger datasets. Addressing this problem is essential in a world with ever-increasing amounts of information.
- Handling High-Dimensional Data – Future systems may be able to cluster data with thousands of dimensions.
- Dealing with Noise and Outliers – Specialists hope to enhance the ability of their clustering systems to reduce noise and lessen the influence of outliers.
- Dynamic Data and Evolving Clusters – Updates can change entire clusters. Professionals will need to adapt to this environment to retain efficiency.
Elevate Your Data Mining Knowledge
There are a vast number of techniques for clustering in machine learning. From centroid-based solutions to density-focused approaches, you can take many directions when grouping data.
Mastering them is essential for any data miner, as they provide insights into crucial information. On top of that, the data science industry is expected to hit nearly $26 billion by 2026, which is why clustering will become even more prevalent.
Related posts
Source:
- Authority Magazine Medium, Published on September 15th, 2024.
Gaining hands-on experience through projects, internships, and collaborations is vital for understanding how to apply AI in various industries and domains. Use Kaggle or get a free cloud account and start experimenting. You will have projects to discuss at your next interviews.
By David Leichner, CMO at Cybellum
14 min read
Artificial Intelligence is now the leading edge of technology, driving unprecedented advancements across sectors. From healthcare to finance, education to environment, the AI industry is witnessing a skyrocketing demand for professionals. However, the path to creating a successful career in AI is multifaceted and constantly evolving. What does it take and what does one need in order to create a highly successful career in AI?
In this interview series, we are talking to successful AI professionals, AI founders, AI CEOs, educators in the field, AI researchers, HR managers in tech companies, and anyone who holds authority in the realm of Artificial Intelligence to inspire and guide those who are eager to embark on this exciting career path.
As part of this series, we had the pleasure of interviewing Zorina Alliata.
Zorina Alliata is an expert in AI, with over 20 years of experience in tech, and over 10 years in AI itself. As an educator, Zorina Alliata is passionate about learning, access to education and about creating the career you want. She implores us to learn more about ethics in AI, and not to fear AI, but to embrace it.
Thank you so much for joining us in this interview series! Before we dive in, our readers would like to learn a bit about your origin story. Can you share with us a bit about your childhood and how you grew up?
I was born in Romania, and grew up during communism, a very dark period in our history. I was a curious child and my parents, both teachers, encouraged me to learn new things all the time. Unfortunately, in communism, there was not a lot to do for a kid who wanted to learn: there was no TV, very few books and only ones that were approved by the state, and generally very few activities outside of school. Being an “intellectual” was a bad thing in the eyes of the government. They preferred people who did not read or think too much. I found great relief in writing, I have been writing stories and poetry since I was about ten years old. I was published with my first poem at 16 years old, in a national literature magazine.
Can you share with us the ‘backstory’ of how you decided to pursue a career path in AI?
I studied Computer Science at university. By then, communism had fallen and we actually had received brand new PCs at the university, and learned several programming languages. The last year, the fifth year of study, was equivalent with a Master’s degree, and was spent preparing your thesis. That’s when I learned about neural networks. We had a tiny, 5-node neural network and we spent the year trying to teach it to recognize the written letter “A”.
We had only a few computers in the lab running Windows NT, so really the technology was not there for such an ambitious project. We did not achieve a lot that year, but I was fascinated by the idea of a neural network learning by itself, without any programming. When I graduated, there were no jobs in AI at all, it was what we now call “the AI winter”. So I went and worked as a programmer, then moved into management and project management. You can imagine my happiness when, about ten years ago, AI came back to life in the form of Machine Learning (ML).
I immediately went and took every class possible to learn about it. I spent that Christmas holiday coding. The paradigm had changed from when I was in college, when we were trying to replicate the entire human brain. ML was focused on solving one specific problem, optimizing one specific output, and that’s where businesses everywhere saw a benefit. I then joined a Data Science team at GEICO, moved to Capital One as a Delivery lead for their Center for Machine Learning, and then went to Amazon in their AI/ML team.
Can you tell our readers about the most interesting projects you are working on now?
While I can’t discuss work projects due to confidentiality, there are some things I can mention! In the last five years, I worked with global companies to establish an AI strategy and to introduce AI and ML in their organizations. Some of my customers included large farming associations, who used ML to predict when to plant their crops for optimal results; water management companies who used ML for predictive maintenance to maintain their underground pipes; construction companies that used AI for visual inspections of their buildings, and to identify any possible defects and hospitals who used Digital Twins technology to improve patient outcomes and health. It is amazing to see how much AI and ML are already part of our everyday lives, and to recognize some of it in the mundane around us.
None of us are able to achieve success without some help along the way. Is there a particular person who you are grateful for who helped get you to where you are? Can you share a story about that?
When you are young, there are so many people who step up and help you along the way. I have had great luck with several professors who have encouraged me in school, and an uncle who worked in computers who would take me to his office and let me play around with his machines. I now try to give back and mentor several young people, especially women who are trying to get into the field. I volunteer with AnitaB and Zonta, as well as taking on mentees where I work.
As with any career path, the AI industry comes with its own set of challenges. Could you elaborate on some of the significant challenges you faced in your AI career and how you managed to overcome them?
I think one major challenge in AI is the speed of change. I remember after spending my Christmas holiday learning and coding in R, when I joined the Data Science team at GEICO, I realized the world had moved on and everyone was now coding in Python. So, I had to learn Python very fast, in order to understand what was going on.
It’s the same with research — I try to work on one subject, and four new papers are published every week that move the goal posts. It is very challenging to keep up, but you just have to adapt to continuously learn and let go of what becomes obsolete.
Ok, let’s now move to the main part of our interview about AI. What are the 3 things that most excite you about the AI industry now? Why?
1. Creativity
Generative AI brought us the ability to create amazing images based on simple text descriptions. Entire videos are now possible, and soon, maybe entire movies. I have been working in AI for several years and I never thought creative jobs will be the first to be achieved by AI. I am amazed at the capacity of an algorithms to create images, and to observe the artificial creativity we now see for the first time.
2. Abstraction
I think with the success and immediate mainstream adoption of Generative AI, we saw the great appetite out there for automation and abstraction. No one wants to do boring work and summarizing documents; no one wants to read long websites, they just want the gist of it. If I drive a car, I don’t need to know how the engine works and every equation that the engineers used to build it — I just want my car to drive. The same level of abstraction is now expected in AI. There is a lot of opportunity here in creating these abstractions for the future.
3. Opportunity
I like that we are in the beginning of AI, so there is a lot of opportunity to jump in. Most people who are passionate about it can learn all about AI fully online, in places like Open Institute of Technology. Or they can get experience working on small projects, and then they can apply for jobs. It is great because it gives people access to good jobs and stability in the future.
What are the 3 things that concern you about the AI industry? Why? What should be done to address and alleviate those concerns?
1. Fairness
The large companies that build LLMs spend a lot of energy and money into making them fair. But it is not easy. Us, as humans, are often not fair ourselves. We even have problems agreeing what fairness even means. So, how can we teach the machines to be fair? I think the responsibility stays with us. We can’t simply say “AI did this bad thing.”
2. Regulation
There are some regulations popping up but most are not coordinated or discussed widely. There is controversy, such as regarding the new California bill SB1047, where scientists take different sides of the debate. We need to find better ways to regulate the use and creation of AI, working together as a society, not just in small groups of politicians.
3. Awareness
I wish everyone understood the basics of AI. There is denial, fear, hatred that is created by doomsday misinformation. I wish AI was taught from a young age, through appropriate means, so everyone gets the fundamental principles and understands how to use this great tool in their lives.
For a young person who would like to eventually make a career in AI, which skills and subjects do they need to learn?
I think maybe the right question is: what are you passionate about? Do that, and see how you can use AI to make your job better and more exciting! I think AI will work alongside people in most jobs, as it develops and matures.
But for those who are looking to work in AI, they can choose from a variety of roles as well. We have technical roles like data scientist or machine learning engineer, which require very specialized knowledge and degrees. They learn computing, software engineering, programming, data analysis, data engineering. There are also business roles, for people who understand the technology well but are not writing code. Instead, they define strategies, design solutions for companies, or write implementation plans for AI products and services. There is also a robust AI research domain, where lots of scientists are measuring and analyzing new technology developments.
With Generative AI, new roles appeared, such as Prompt Engineer. We can now talk with the machines in natural language, so speaking good English is all that’s required to find the right conversation.
With these many possible roles, I think if you work in AI, some basic subjects where you can start are:
- Analytics — understand data and how it is stored and governed, and how we get insights from it.
- Logic — understand both mathematical and philosophical logic.
- Fundamentals of AI — read about the history and philosophy of AI, models of thinking, and major developments.
As you know, there are not that many women in the AI industry. Can you advise what is needed to engage more women in the AI industry?
Engaging more women in the AI industry is absolutely crucial if you want to build any successful AI products. In my twenty years career, I have seen changes in the tech industry to address this gender discrepancy. For example, we do well in school with STEM programs and similar efforts that encourage girls to code. We also created mentorship organizations such as AnitaB.org who allow women to connect and collaborate. One place where I think we still lag behind is in the workplace. When I came to the US in my twenties, I was the only woman programmer in my team. Now, I see more women at work, but still not enough. We say we create inclusive work environments, but we still have a long way to go to encourage more women to stay in tech. Policies that support flexible hours and parental leave are necessary, and other adjustments that account for the different lives that women have compared to men. Bias training and challenging stereotypes are also necessary, and many times these are implemented shoddily in organizations.
Ethical AI development is a pressing concern in the industry. How do you approach the ethical implications of AI, and what steps do you believe individuals and organizations should take to ensure responsible and fair AI practices?
Machine Learning and AI learn from data. Unfortunately, lot of our historical data shows strong biases. For example, for a long time, it was perfectly legal to only offer mortgages to white people. The data shows that. If we use this data to train a new model to enhance the mortgage application process, then the model will learn that mortgages should only be offered to white men. That is a bias that we had in the past, but we do not want to learn and amplify in the future.
Generative AI has introduced a new set of fresh risks, the most famous being the “hallucinations.” Generative AI will create new content based on chunks of text it finds in its training data, without an understanding of what the content means. It could repeat something it learned from one Reddit user ten years ago, that could be factually incorrect. Is that piece of information unbiased and fair?
There are many ways we fight for fairness in AI. There are technical tools we can use to offer interpretability and explainability of the actual models used. There are business constraints we can create, such as guardrails or knowledge bases, where we can lead the AI towards ethical answers. We also advise anyone who build AI to use a diverse team of builders. If you look around the table and you see the same type of guys who went to the schools, you will get exactly one original idea from them. If you add different genders, different ages, different tenures, different backgrounds, then you will get ten innovative ideas for your product, and you will have addressed biases you’ve never even thought of.
Read the full article below:
Source:
- Il Sole 24 Ore, Published on July 29th, 2024 (original article in Italian).
By Filomena Greco
It is called OPIT and it was born from an idea by Riccardo Ocleppo, entrepreneur, director and founder of OPIT and second generation in the company; and Francesco Profumo, former president of Compagnia di Sanpaolo, former Minister of Education and Rector of the Polytechnic University of Turin. “We wanted to create an academic institution focused on Artificial Intelligence and the new formative paths linked to this new technological frontier”.
How did this initiative come about?
“The general idea was to propose to the market a new model of university education that was, on the one hand, very up-to-date on the topic of skills, curricula and professors, with six degree paths (two three-year Bachelor degrees and four Master degrees) in areas such as Computer Science, AI, Cybersecurity, Digital Business; on the other hand, a very practical approach linked to the needs of the industrial world. We want to bridge a gap between formal education, which is often too theoretical, and the world of work and entrepreneurship.”
What characterizes your didactic proposal?
“Ours is a proprietary teaching model, with 45 teachers recruited from all over the world who have a solid academic background but also experience in many companies. We want to offer a study path that has a strong business orientation, with the aim of immediately bringing added value to the companies. Our teaching is entirely in English, and this is a project created to be international, with the teachers coming from 20 different nationalities. Italian students last year were 35% but overall the reality is very varied.”
Can you tell us your numbers?
“We received tens of thousands of applications for the first year but we tried to be selective. We started the first two classes with a hundred students from 38 countries around the world, Italy, Europe, USA, Canada, Middle East and Africa. We aim to reach 300 students this year. We have accredited OPIT in Malta, which is the only European country other than Ireland to be native English speaking – for us, this is a very important trait. We want to offer high quality teaching but with affordable costs, around 4,500 euros per year, with completely online teaching.”
Read the full article below (in Italian):
Have questions?
Visit our FAQ page or get in touch with us!
Write us at +39 335 576 0263
Get in touch at hello@opit.com
Talk to one of our Study Advisors
We are international
We can speak in: