Published in Towards Data Science·PinnedMember-onlyWhy Sigmoid: A Probabilistic PerspectiveDo you know why the output of the sigmoid function can be interpreted as a probability? — If you have taken any machine learning courses before, you must have come across logistic regression at some point. There is this sigmoid function that links the linear predictor to the final prediction. Depending on the course you took, this sigmoid function is often pulled out of thin air and…Machine Learning15 min readMachine Learning15 min read
Published in Towards Data Science·Jan 28, 2021Member-onlyIntroducing the Loss Landscape Animation Python PackageIn my previous article Visualizing Optimization Trajectory of Neural Nets, I showed a number of animated figures to demonstrate the training process of neural networks. Since then some readers expressed interest in the code, so I ported it to a Python package and published it on PyPI. …Machine Learning5 min readMachine Learning5 min read
Published in Towards Data Science·Jan 20, 2021Member-onlyA 3-Minute Review of PCA: Compression and RecoveryThe handiest visual note of PCA — Nowadays, the knowledge depth of data scientists and ML engineers is often judged by their regurgitation of the math and implementation details of an algorithm. I disagree with this approach. The reality is, nobody can remember every detail, and that’s okay. You don’t need to know how to implement an…Machine Learning5 min readMachine Learning5 min read
Published in The Startup·Dec 22, 2020Member-onlyI Created an Alexa Skill to Settle an Argument With My WifeHow to get started building Alexa skills for things you are too lazy to search online — I moved to New York City from California two years ago. Having been spoiled by the Californian sunshine and nice weather for several years, I forgot how it’s like living in a city with a lot of precipitation. Sometimes I feel the rain never stops. No matter what season it…Alexa10 min readAlexa10 min read
Published in Towards Data Science·Nov 19, 2020Member-onlyHow I Designed My Own Full-Stack ML Engineering DegreeThe road to end-to-end data scientist/machine learning engineer — Earlier this year I came across a viral Twitter thread by Randall Kanna about how to create one’s own computer science degree with free online content. It was not only excellent for people who don’t have prior knowledge in computer science, it’s also valuable for new software engineers who didn’t…Machine Learning13 min readMachine Learning13 min read
Published in Level Up Coding·Jul 31, 2020Member-onlyColonize Space with Fractal TreesA quick guide to fractals and the Space Colonization algorithm — In this article, I’m going to code up some special kind of squiggly shapes that might not help us colonize the galaxy any time soon, but probably will bend your mind and make math fun again. The subject is called fractals. What are Fractals? Before answering this question, let’s first look at some…Fractals7 min readFractals7 min read
Published in Towards Data Science·Jul 30, 2020Member-onlyA 3-Minute Review of Rejection Sampling: Simulate Any DistributionA short probability and algorithm tutorial that’s worth your while — When you want some values from a certain probability distribution, say, a normal distribution, you could simply call rnorm in R, or numpy.random.normal in Python. But have you ever wondered how they do it under the hood? The underlying idea is incredibly simple yet powerful. In this article, I'm going…Probability3 min readProbability3 min read
Published in Towards Data Science·Jun 27, 2020Member-onlyBuilding A Mental Model for BackpropagationBy implementing your own deep learning framework in Python — As the beating heart of deep learning, a solid understanding of backpropagation is required for any deep learning practitioner. Although there are a lot of good resources that explain backpropagation on the internet already, most of them explain from very different angles and each is good for a certain type…Deep Learning7 min readDeep Learning7 min read
Published in Towards Data Science·May 16, 2020Member-onlyVisualizing Optimization Trajectory of Neural NetsUpdate: I have ported the code to a Python package here. Feel free to experiment and produce similar plots like the ones in this post! In the previous post, I showed some animated plots for the training process of linear regression and logistic regression. Developing a good “feel” of how…Machine Learning7 min readMachine Learning7 min read
Published in The Startup·Apr 18, 2020Member-onlyVisualizing Optimization in Linear Regression and Logistic RegressionThis is one post in a series for machine learning optimization animations. Each plot can serve as a flashcard for easy consumption. If you are like me, you may prefer looking at pictures that move to pages of Greek symbols when it comes to learning math. It’s more intuitive, more…Machine Learning8 min readMachine Learning8 min read
