Alexander Mathiasen

Alexander Mathiasen

My Machine Learning Videos and iPython Notebooks

Linear Models: DONE

Perceptron: DONE
Linear Regression: DONE
Logistic Regression: DONE
Feature Transform: DONE

Learning Theory: DONE

Overfitting: ..
Hoeffding and Union Bound: ..
VC Dimensions: DONE
Bias Variance Decomposition: DONE

Support Vector Machines: ..

Maximial Margin: ..
Hinge Loss Formulation: ..
The Real Deal (Duality, Lagrangian, SMO): ..
Kernels and Mercers Theorem: ..

Neural Networks: ..

Feed Forward Neural Networks: ..
Backpropagation and Gradient Descent: ..
Convolutional Neural Networks: ..

Ensemble Methods: DONE

Bias Variance Decomposition: DONE
Decision Trees: ..
Boosting: DONE
Bagging: ..

Hidden Markov Models: DONE

From IID to Markov Assumption: DONE
Graphical Models: DONE
Viterbi Decoding: DONE
Posterior Decoding: DONE
Backtracking: ..
Training By Counting: ..
Viterbi Training: ..
Baum-Welch (EM): ..

Unsupervised Learning: ..

k-Means clustering: ..
Expectation Maximization: ..
Evaluating Clusterings: ..
PCA: ..
Johnson-Lindensrauss: ..
AutoEncoder: ..

(Later)Reinforcement Learning


It's taking more time to create this material than I initially estimated. I'll be adding pieces of material as soon as it's done.

About Me

My deepest passion

Music, Algorithms or Quantum Computing, it doesn't really matter. I love learning. Truth be told, I am not quite sure why. I just always did. From learning to play the guitar, perform a painful yoga move to playing table football. That said, there is one topic I appreciate so much more than all the others.

Learning about learning.

The first time I encountered this idea was during an Psychology intro class. Five years later I'm studying the mathematics of machines trying to learn (the cool kids like to call this Machine Learning). If you're ever lucky enough to meet me, you'll quickly realize I'll never stop talking about Machine Learning.

Well, I might make a brief exception to discuss recent advances in Quantum Computing. But only because these guys managed to do Machine Learning ;-)

Cool Stuff I made

Curriculum Vitae



Ph. D. Student

Aarhus University

I'm doing Machine Learning supervised by Kasper. He is infinitely cooler than I am (he ran a 12k 15 min faster than me). Recently we had a nice breakthrough related to boosting. Stay tuned for awesome algorithms!

I did electives in Complexity Theory, Quantum Machine Learning, IO algorithms, Computational Geometry and Algorithmic Gems.


Bachelor Computer Science

Aarhus University

Electives in Machine Learning, Bioinformatics and Dimensionality Reduction for k-Means (Johnson-Lindenstrauss lemma).



Teknisk Gymnasium Sønderjylland

I was very fortunate to study A levels in Physics, Mathematics, Chemistry, Electronics and Literature.


Fall 2017

Teaching Assistant - Machine Learning

Aarhus University

I had the best time teaching a class of 30 lovely students. The class consisted of bachelor/master CS/Math-econ students and a single physics Ph. D. student.

Besides teaching, I helped the lecturers prepare exercises/assignments in iPython Notebooks with Daniel. Check it out on my Github.

To help my students for the exam, I'm currently preparing iPython notebooks with all the algorithms; check it out on here.

Spring 2017

Teaching Assistant - Algorithms and Data Structures

Aarhus University

Algorithms are at the heart of computer science. This semester I introduced 30 first year Computer Science students to divide and conquer, dynamic programming, greedy algorithms and several smart constructions using hashing.


Teaching Assistant - Computability and Logics

Aarhus University

This semester I taught computability and logics to a class of 30 first year computer science students. The course starts by introducing Turing Machines and ends by proving a simplified version of Gódels incompleteness Theorem.


Gymnasium Outreach

Aarhus University.

Deciding if, what and where to study can be very difficult. To help potential students make an informed choice, Aarhus University has this awesome program where University students visit Gymnasiums and explain what University is like.

During this job I visited a few Gymnasiums and talked about Computer Science, what it takes, and why it's awesome.


Study Cafe TA

Teknisk Gymnasium Sønderjylland

During gymnasium I enjoyed teaching my fellow students in the study cafe. I had the best of times teaching with my all-time-best-amigo Kristian.


My thoughts on cutting edge research.


Get in Touch

Get in Touch

On a day-to-day you can find me in the Nygaard building at Aarhus University. I'm in office 331, feel free to drop by for a chat.

Aarhus, Denmark