Math, Statistics, Computer, AI, Finance Market, and quants

Photo by Chris Liverani on Unsplash

Two years ago, I participated in the Kaggle competition Using News to Predict Stock Movements hosted by Two Sigma which is a hedge fund that uses AI, machine learning, and distributed computing, for its trading strategies.

Asynchronous JavaScript Programming

JavaScript, generally speaking, is single-threaded. Due to this “problem”, all Javascript network operations and browser events performance is affected. To fix such problems, browsers allow us to run certain operations asynchronously. With the continuous introduction of new JavaScript features, Javascript asynchronous programming has also experienced the evolution from callbacks to promises and then to async/await.


We can use the callbacks function to achieve asynchronous operation. A callback, also known as a “call-after” function, passed an argument to another function. A callback function can run after another function has finished.

The Completion type is a Record used to explain the runtime propagation of value and control flow such as the behaviour of statements (break, continue, return and throw) that perform nonlocal transfers of control.

— ECMAScript Specification

What does it mean?

Although we have been using javascript for several years, we still may not know or understand Completion Record.

In this article, we will learn more about how javascript uses Completion Record to control the execution of statements.

Completion Record

From the above specification, we can get:

  1. The Completion type is a Record. The Record type is used to describe data aggregations…

A glimpse of human work in the post-pandemic era

Morning, wake up, wash my face, eat breakfast, put on my hoodie, take on the coat, carry my computer bag, and say goodbye to my family. Go out of my bedroom, walk through the corridor, open the sliding door, enter the study room, take off the coat, sit at the desk, take out my MacBook Pro, put on the headphones, and start working.

You read that right. I have worked like this since the lockdown of the Covid-19. Compare to the 1.5-hour commute before the pandemic, it now only takes 15 seconds — from the bedroom to the study room.


Tesla AI Day, Tesla Bot, Apple AirTag Story

Hi everyone, I’m here again. Let’s take a look at what’s new in technology this week.


pandas is a fast, powerful, flexible, and easy-to-use open-source data analysis and manipulation tool, built on top of the Python programming language.

This article will share some advanced pandas techniques I used in data analysis and machine learning tasks.


  • groupby() + agg(), apply(), transform() and its Practically Scenario and Performance Comparison
  • Combing data: merge(),concat(),join(),append()

Source Data: train.csv, a fake car sales data I generated with a python code.

Tabnine, IntelliCode, IntelliSense, and GitHub Coilpot

Photo by Markus Spiske on Unsplash

Recently GitHub released an AI pair programmer — GitHub Copilot. It is available first as a Visual Studio Code(VS Code) extension. For us, you still need to submit an application now and be invited before you can try it.

This news prompted me to review the available smart or AI programming tools. From this, we can observe what capabilities these tools provide and whether they are actually helpful to our daily programming work.

I am mainly going to test the Visual Studio Code extensions of IntelliSense, IntelliCode, aiXcoder, Kite, and Tabnine. The code used in the test is a python…


WWDC21, Tesla Model S Plaid, Apple Car Rumors, Jeff Bezos & Blue Origin

Hi everyone, I’m here again. Let's take a look at what’s new in technology this week.



Building your own blog fastly, simply and powerful

Photo by Annie Spratt on Unsplash

From handcrafted HTML to Wordpress, to site generator, personal blogs (or personal websites) are also from static sites (HTML + CSS), through dynamic sites (PHP + MySQL), to static sites(markdown + site generator).

If you want to have a blog of your own, using the site generator is a better choice. This article will recommend you 4 useful site generators, which have been pick and choose by me.

There are many site generators here, and I picked these 4 generators from two main factors: platform and usability.


InsideThisWeekTech May22-29, 2021

WWDC21, Tesla removal radar, Google ML Summit, Airbnb 100+ Upgrades, Twitter Blue



Jason Zhang

Software Engineer, Kaggle Competitions Expert

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