Machine Learning
Machine Learning: what it really is, and why it's changing everything
January 8, 2025
Lorenzo Mascia
13 min read
Machine Learning is one of those terms that almost everyone has heard, but very few people stop to unpack properly. It's often treated as a magical black box, something vaguely intelligent that "just works" behind the scenes. In reality, Machine Learning is both more grounded and more disruptive than the hype suggests, and understanding what it really is helps explain why it's reshaping entire industries...
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Machine Learning
Data, features, and models: the foundations of Machine Learning
January 22, 2025
Lorenzo Mascia
11 min read
When people talk about Machine Learning, the conversation often jumps straight to models, algorithms, or impressive results. But this skips the most important part of the story. Machine Learning does not start with models. It starts with data, it takes shape through features, and only then does it become a model. Understanding this flow is essential, because most real-world successes and failures in Machine Learning come from these foundations...
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Machine Learning
Supervised vs Unsupervised Learning: when to use one or the other
February 10, 2025
Lorenzo Mascia
10 min read
One of the first distinctions people encounter in Machine Learning is the divide between supervised and unsupervised learning. At first glance, this separation looks technical, almost academic. In practice, it reflects two fundamentally different ways of approaching problems, and choosing between them often has more to do with the nature of your data and your goals than with the algorithms themselves...
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Machine Learning
From problem to model: how to turn an idea into a Machine Learning system
February 28, 2025
Lorenzo Mascia
13 min read
Every Machine Learning project starts with an idea. Sometimes it is ambitious, sometimes vague, sometimes deceptively simple. "We want to predict churn." "We want to detect anomalies." "We want to recommend better content." The hard part is not having the idea itself, but transforming it into something that a Machine Learning system can actually learn and execute...
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Machine Learning
Regression and classification: the first algorithms to truly master
March 18, 2025
Lorenzo Mascia
11 min read
When people begin studying Machine Learning, regression and classification are often the first concepts they encounter. This is not by chance. These two problem types form the backbone of most real-world Machine Learning systems, and understanding them well creates a mental framework that applies far beyond any specific algorithm...
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Machine Learning
Overfitting, underfitting, and bias: the mistakes every model makes
April 8, 2025
Lorenzo Mascia
12 min read
No Machine Learning model is perfect. No matter how advanced the algorithm or how large the dataset, every model makes mistakes. Understanding these mistakes is not a sign of weakness in Machine Learning; it is what allows us to use it responsibly and effectively. Among the most important concepts to grasp are overfitting, underfitting, and bias...
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Machine Learning
How to evaluate a Machine Learning model (beyond accuracy)
April 28, 2025
Lorenzo Mascia
11 min read
When people first evaluate a Machine Learning model, accuracy often becomes the default metric. It feels intuitive and reassuring. A higher accuracy seems to mean a better model. But accuracy alone tells a very incomplete story, and in many real-world scenarios it can be actively misleading...
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Machine Learning
Feature engineering: the hidden art behind models that actually work
May 15, 2025
Lorenzo Mascia
12 min read
When Machine Learning systems succeed, the spotlight often falls on the model. People talk about architectures, algorithms, and training tricks. Yet in many real-world projects, the decisive factor lies elsewhere. It lies in feature engineering, the quiet, often invisible process that shapes raw data into something a model can truly learn from...
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Machine Learning
From notebook to production: bringing a Machine Learning model into the real world
June 3, 2025
Lorenzo Mascia
11 min read
Building a Machine Learning model in a notebook often feels like crossing the finish line. The data is clean, the metrics look good, and the predictions make sense. But in reality, this is only the beginning. The hardest and most consequential part of Machine Learning starts when a model leaves the controlled environment of experimentation and enters the real world...
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Machine Learning
Machine Learning today: limits, myths, and what it really takes to work in the field
June 20, 2025
Lorenzo Mascia
13 min read
Machine Learning today sits in a strange position. It is everywhere and yet deeply misunderstood. Headlines talk about breakthroughs, automation, and intelligence, while everyday practice is often slower, messier, and far more human than people expect. To understand what Machine Learning really is today, it helps to separate what it can do from what we hope it can do...
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Machine Learning
Linear Regression: when simplicity beats complexity
July 8, 2025
Lorenzo Mascia
15 min read
In a field that often celebrates complexity, Linear Regression stands as a quiet reminder that simple ideas can be remarkably powerful. It is one of the oldest and most studied techniques in Machine Learning, and yet it remains deeply relevant. Not because it is flashy, but because it forces clarity. Linear Regression does not hide behind layers of abstraction; it exposes its assumptions openly and invites you to think carefully about the relationship between data and predictions...
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Machine Learning
Polynomial Regression: modeling non-linear relationships without deep learning
July 22, 2025
Lorenzo Mascia
14 min read
Linear Regression teaches an important lesson: simplicity can be powerful. But reality is rarely perfectly linear. Many real-world relationships curve, accelerate, or change direction as inputs grow. This is where Polynomial Regression enters the picture. It extends the linear model just enough to capture non-linear behavior, without jumping straight into complex or opaque techniques like deep learning...
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Machine Learning
k-Nearest Neighbors (k-NN): learning from your neighbors
August 5, 2025
Lorenzo Mascia
13 min read
k-Nearest Neighbors is one of the most intuitive algorithms in Machine Learning, and precisely for this reason it is often underestimated. There is no explicit training phase, no complex optimization, no hidden parameters learned in advance. And yet, k-NN captures a powerful idea: similar problems tend to have similar solutions. Instead of learning a global model of the world, k-NN reasons locally, using the past as a reference point for the present...
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Machine Learning
Decision Trees: how a model makes decisions step by step
August 20, 2025
Lorenzo Mascia
12 min read
Decision Trees are one of the most intuitive models in Machine Learning, because they mirror the way humans often reason about decisions. Instead of learning a single mathematical formula, a Decision Tree breaks a problem down into a sequence of simple questions. Each question narrows the possibilities, step by step, until a final decision is reached. This structure makes Decision Trees uniquely transparent in a field that often struggles with interpretability...
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Machine Learning
Random Forest: why a collection of trees is stronger than a single one
September 5, 2025
Lorenzo Mascia
14 min read
A single Decision Tree is easy to understand, intuitive, and powerful. But it has a well-known weakness: it is fragile. Small changes in the data can lead to very different trees, and if the tree grows too deep, it tends to memorize rather than generalize. Random Forest was created to address exactly this problem, not by abandoning trees, but by embracing them in numbers...
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Machine Learning
Gradient Boosting: building strong models from weak ones
September 20, 2025
Lorenzo Mascia
15 min read
Gradient Boosting represents a shift in how we think about learning. Instead of building many independent models and averaging their opinions, it builds models sequentially, each one learning from the mistakes of the previous ones. The idea is both simple and powerful: rather than trying to get everything right at once, you improve step by step, focusing attention where the current model is failing...
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Machine Learning
Support Vector Machines (SVM): maximizing the margin to classify better
October 5, 2025
Lorenzo Mascia
14 min read
Support Vector Machines occupy a special place in Machine Learning. They are rigorous, geometric, and built around a very precise idea of what it means to make a good decision. Instead of trying to be right as often as possible on the training data, SVMs focus on being confidently right. They do this by maximizing the margin, the distance between the decision boundary and the closest data points from each class...
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Machine Learning
Naive Bayes: probabilistic simplicity that works surprisingly well
October 20, 2025
Lorenzo Mascia
11 min read
Naive Bayes is one of those algorithms that often gets introduced early and then quietly underestimated. It looks too simple to be powerful. Its assumptions seem unrealistic. And yet, it consistently performs well in real-world applications, sometimes rivaling far more complex models. Understanding why this happens is a great way to deepen your intuition about Machine Learning itself...
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Machine Learning
Clustering with k-Means and DBSCAN: finding structure in unlabeled data
November 5, 2025
Lorenzo Mascia
16 min read
Not all Machine Learning problems come with clear answers. Often, there are no labels, no predefined categories, and no obvious notion of what the "correct" output should be. In these situations, the goal shifts from prediction to discovery. Clustering is about uncovering structure that already exists in the data, even when no one has explicitly defined it. Among clustering techniques, k-Means and DBSCAN represent two very different philosophies for how this discovery should happen...
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Machine Learning
A practical comparison of Machine Learning algorithms: same dataset, different models
November 20, 2025
Lorenzo Mascia
17 min read
One of the fastest ways to really understand Machine Learning algorithms is to stop studying them in isolation and start comparing them on the same problem. On paper, many models sound similar. In practice, they behave very differently when faced with the same data, the same features, and the same objective. This kind of comparison is where theory turns into intuition...
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