with a Real-World Example in Python


Randomized experiment is the gold standard to examine causality. However, it’s often the case that we cannot conduct experiments for a variety of practical reasons and have to rely on observational data. Matching is a method used to approximate experimental results to recover the causal effect from observational data.


With an Example Implemented Step by Step in Python

This article introduces and implements the framework of propensity score method from Dehejia and Wahba (1999) “Causal Effects in Non-Experimental Studies: Reevaluating the Evaluation of Training Programs,” Journal of the American Statistical Association, Vol. 94, №448 (December 1999), pp. 1053–1062. I will briefly go over the theories and then walk…

With a focus on the experimentation illustrated by an example


The Nobel Prize in Economic Sciences 2021 is awarded to Joshua D. Angrist and Guido W. Imbens “for their methodological contributions to the analysis of causal relationships.”. If you wonder what “ the methodological contributions” are in specific and are willing to dig deeper into the scientific background, you will…

with a Real-World Example in Python

In my last article, I introduced how to estimate propensity score using logistic regression model and do stratification matching step by step. To recap, in practice, the propensity score method is usually done in two steps. First, we estimate the propensity score. …

Build a linear regression model step by step to test the Gauss-Markov assumptions

It seems that nowadays when everyone is so much into all kinds of fancy machine learning algorithms, few people still care to ask: what are the key assumptions required for the Ordinary Least Squares (OLS) regression? How can I test if my model satisfies these assumptions? However, as simple linear…

Analyze the causal effect of class size using linear regression in Python

Randomized experiment or randomized control trial (RCT) is regarded as the gold standard to test causality. In the tech industry, RCT takes the form of online platform experiments and is often called A/B testing.

In this article, I will walk through the potential outcome model underlying the inference of the…

How to perform an economic impact analysis step by step

In this article, I will introduce the Input-Output model framework, explain the structure of an input-output table, and walk through step-by-step how to perform an economic impact analysis.


The Input-Output model is a framework developed by Dr. Leontief, in recognition of which he received the Nobel Prize in Economic Science…

Shuangyuan (Sharon) Wei

data scientist, rock climber

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store