Rajiv’s Data Science Blog

Feature Engineering with Graphs

news
code
analysis
Real estate is all about location. Graphs make it possible to do this with your learning problems. Imbalanced datasets are pervasive in real life: Modeling rare diseases and…
Sep 23, 2025
Rajiv Sambasivan

Unsupervised Learning and Graphs

news
code
analysis
Graph problems that you solve routinely fall into one of the following categories:
Sep 23, 2025
Rajiv Sambasivan

Heterogeneity in Modeling

news
code
analysis
In previous posts, I have frequently mentioned the term heterogeneity. Since it is a recurring concept, I wanted to explain what I was talking about
Aug 3, 2025
Rajiv Sambasivan

Graph From Relations

news
code
analysis
If you have had a chance to look at the Olist Case Study, you can see that even within one geographic region, IID (Independent Identically Distributed) is not a reasonable…
Jul 27, 2025
Rajiv Sambasivan

Understanding Coffee Prices

news
code
analysis
The question of whether I will continue paying these high prices for coffee was a “nerd itch” I simply had to scratch. Below is a plot showing the coffee prices (in cents…
Jun 21, 2025
Rajiv Sambasivan

Descriptive Analytics Repository

news
code
analysis
I have a created a github repository for descriptive analytics. The goal of this reository is to illustrate the utility of decribing facets of your data in relation to…
Jun 20, 2025
Rajiv Sambasivan

Descriptive Analysis of Olist Customers in SP, 2017

news
code
analysis
This post is the first sketch of a descriptive analysis task for the Olist dataset. Last week I had an incremental update. If you saw that, you’d see that this week’s…
Jun 9, 2025
Rajiv Sambasivan

Descriptive Analytics, the lost idea in the current AI hype

news
code
analysis
In the current wave of excitement around AI and generative technologies, the value of descriptive analytics as a foundation for predictive modeling is often overlooked.…
May 30, 2025
Rajiv Sambasivan

Stochastic Optimization

news
code
analysis
Synergy and complementarity are terms that aptly describe the relationship between machine learning and optimization. In machine learning, optimization is often the tool…
May 25, 2025
Rajiv Sambasivan

Accuracy, is that what we are after?

news
code
analysis
Is accuracy the ultimate goal of a data scientist’s work? A recent WhatsApp forward I received portrayed data scientists as being singularly focused on model accuracy, as if…
May 5, 2025
Rajiv Sambasivan

The Magic Pill Approach

news
code
analysis
This post is more of a rant, really. I’m fine with asking ChatGPT for movie recommendations on Netflix or Prime, but when it comes to answering complex, nuanced questions…
May 1, 2025
Rajiv Sambasivan

Using Hidden Markov Models with the Coffee Prices Data

news
code
analysis
I started writing about coffee prices kind of on a whim—mostly because I wanted to try out this tool called quarto that I’d heard good things about. At the same time, I was…
Apr 26, 2025
Rajiv Sambasivan

Predictive Modeling without Supporting Data Analysis

news
code
analysis
In my opinion, relying on models without prior data analysis is problematic. This is particularly true for business applications that work with regular tabular data. While…
Apr 23, 2025
Rajiv Sambasivan

Chat GPT and Data Analysis

news
code
analysis
For a while now I have been meaning to explore how Copilot and Chat GPT are useful for data analysis. I have also been meaning to transition to Quarto for a while, so I…
Apr 23, 2025
Rajiv Sambasivan
No matching items