There are many axes along which we can classify data scientists. We can classify based on the primary specialty, in terms “analytics”, “business intelligence” and “machine learning”. We can classify based on domain, into “financial data scientists” and “retail data scientists” and “industrial data scientists”. We can classify by the choice of primary software tool,…
Stocks and flows
One common mistake even a lot of experienced analysts make is comparing stocks to flows. Recently, for example, Apple’s trillion dollar valuation was compared to countries’ GDP. A few years back, an article compared the quantum of bad loans in Indian banks to the country’s GDP. Following an IPL auction a few years back, a…
New blog on visualisations
For a while now I’ve been commenting on visualisations on Twitter, pointing out the good (and especially bad) graphs. I also have a “chart of the edition” section in my newsletter. Recently, the legendary Krish Ashok suggested that I collect all these bad visualisations in a Tumblr, and I decided to oblige. You can follow…
Why AI will always be biased
Out on Marginal Revolution, Alex Tabarrok has an excellent post on why “sexism and racism will never diminish“, even when people on the whole become less sexist and racist. The basic idea is that there is always a frontier – even when we all become less sexist or racist, there will be people who will…
Podcast on election forecasting
I recorded a podcast for Pragati on opinion polls, exit polls, election forecasting and all such. You can listen to it right here, or on the podcast page here. The Pragati Podcast is available on all major podcast apps.
Beer and diapers: Netflix edition
When we started using Netflix last May, we created three personas for the three of us in the family – “Karthik”, “Priyanka” and “Berry”. At that time we didn’t realise that there was already a pre-created “kids” (subsequently renamed “children” – don’t know why that happened) persona there. So while Priyanka and I mostly use…
More on interactive graphics
So for a while now I’ve been building this cricket visualisation thingy. Basically it’s what I think is a pseudo-innovative way of describing a cricket match, by showing how the game ebbs and flows, and marking off the key events. Here’s a sample, from the ongoing game between Chennai Super Kings and Kolkata Knight Riders.…
A banker’s apology
Whenever there is a massive stock market crash, like the one in 1987, or the crisis in 2008, it is common for investment banking quants to talk about how it was a “1 in zillion years” event. This is on account of their models that typically assume that stock prices are lognormal, and that stock…
English Premier League: Goal Difference to points correlation
So I was just looking down the English Premier League Table for the season, and I found that as I went down the list, the goal difference went lower. There’s nothing counterintuitive in this, but the degree of correlation seemed eerie. So I downloaded the data and plotted a scatter-plot. And what do you have?…
Stirring the pile efficiently
Warning: This is a technical post, and involves some code, etc. As I’ve ranted a fair bit on this blog over the last year, a lot of “machine learning” in the industry can be described as “stirring the pile”. Regular readers of this blog will be familiar with this image from XKCD by now: Basically…
Astrology and Data Science
The discussion goes back some 6 years, when I’d first started setting up my data and management consultancy practice. Since I’d freshly quit my job to set up the said practice, I had plenty of time on my hands, and the wife suggested that I spend some of that time learning astrology. Considering that I’ve…
Duckworth Lewis Book
Yesterday at the local council library, I came across this book called “Duckworth Lewis” written by Frank Duckworth and Tony Lewis (who “invented” the eponymous rain rule). While I’d never heard about the book, given my general interest in sports analytics I picked it up, and duly finished reading it by this morning. The good…
More issues with Slack
A long time back I’d written about how Slack in some ways was like the old DBabble messaging and discussion group platform, except for one small difference – Slack didn’t have threaded conversations which meant that it was only possible to hold one thread of thought in a channel, significantly limiting discussion. Since then, Slack…
Generalist and specialist managers
A really long time ago, I’d written this blog post about “comparative advantage” versus “competitive advantage” employees. A competitive advantage employee is better at a particular kind of task or skill compared to the rest of the team, and he is valued for that kind of skill. A comparative advantage employee, on the other hand,…
Ratings revisited
Sometimes I get a bit narcissistic, and check how my book is doing. I log on to the seller portal to see how many copies have been sold. I go to the Amazon page and see what are the other books that people who have bought my book are buying (on the US store it’s…
Freelancing and transaction costs
In the six years of running my own consulting business, I’d forgotten about an essential part that you need to endure as part of a job – piecemeal work. It is fairly often when you’re working for someone else that you get work that is so tiny or insignificant that you can hardly take ownership…
The (missing) Desk Quants of Main Street
A long time ago, I’d written about my experience as a Quant at an investment bank, and about how banks like mine were sitting on a pile of risk that could blow up any time soon. There were two problems as I had documented then. Firstly, most quants I interacted with seemed to be solving…
The nature of the professional services firm
This is yet another rejected section from my soon-t0-be-published book Between the buyer and the seller. In 2006, having just graduated from business school, I started my career working for a leading management consulting firm. This firm had been one of the most sought after employers for students at my school, and the salary they offered…
Scott Adams, careers and correlation
I’ve written here earlier about how much I’ve been influenced by Scott Adams’s career advice about “being in top quartile of two or more things“. To recap, this is what Adams wrote nearly ten years back: If you want an average successful life, it doesn’t take much planning. Just stay out of trouble, go to…
Levels and shifts in analysing games
So Nitin Pai and Pranay Kotasthane have a great graphic on how India should react to China’s aggressions on Doka La. While the analysis is excellent, my discomfort is with the choice of “deltas” as the axes of this payoff diagram, rather than levels. Source: Nitin Pai and Pranay Kotasthane Instead, what might have been…
Selling yourself for job and consulting
So for the first time in over eight years, I’m looking for a job. This was primarily prompted by my move to London earlier this year – a consulting business where you rely on networks rather than a global brand to get new business cannot be easily transplanted. Moreover, as I’d written a year back,…