## Finding the right tech company to work for

I introduce you below the four most valuable sources of information for landing a job at a company that is right for you. Why four? Because I think there are...

## AI in Society: 2. Algorithmic Fairness

Data is to machine learning as fuel is to cars. None of the AI superpowers can be gained without abundant data. But it is not only the quantity of the data t...

## Tackling the Cold Start Problem in Recommender Systems

As part of my machine learning internship at Wish, I’m tackling a common problem in recommender systems called the “cold start problem”. Cold start happens w...

## AI in Society: 1. Interpretability

Can we open the black-box of all the complicated models out there?

## AI in Society: 0. Limitations of Machine Learning Today

Introduction to AI in Society blog series. The impact of AI today is already enormous. But there still are many obstacles to overcome.

## Robust PCA

PCA is great because you can reduce a data matrix to a lower dimension without losing much. Although it is widely used, PCA doesn’t work well when there are ...

## SVD -> PCA

I wrote a blog about Robust PCA. As a prerequisite for the readers, I will explain what SVD and PCA are. As we shall see, PCA is essentially SVD, and learnin...

## EM, Mixture of Gaussians and K-means

This post ties together EM (Expectation Maximization), GMM (Gaussian Mixture Models), K means and variational inference. If you have taken an introductory ma...

## Multivariate Normal Cheatsheet

Multivariate normal (MVN) is used everywhere in machine learning, from simple regressions, linear discriminant analysis, Kalman filters to gaussian processes...

## What regression coefficients really mean

There is nothing in statistics that is as easy as regressions to use but as hard to make a correct interpretation. Especially in causal inference, even the c...

## Formal definition of an experiment

Science experiments, social experiments, thought experiments, … We use the word “experiment” somewhat often in real life. But have you ever wondered what exp...

## The Theory behind AB Testing: Introduction to Causal Inference

If you’ve been working in the tech industry, or have thought about doing so, you’ve probably heard of AB testing. Some of you have even conducted one. The id...

## Is Bell Curve really a Great Intellectual Fraud?

Bell Curve = Great Intellectual Fraud? I recently read a New York Times best-seller titled “Black Swan” by Nicholas Taleb. The book discusses how hard it is ...

## Must-know probability distributions from a single coin toss

There are countless numbers of probability distributions. Some of them are so widely used and beautiful that they deserve a name. Surprisingly, all of those ...