iit-madras on S Anand

Thu, 02 Oct 2025 00:00:00 +0000

Tools in Data Science Sep 2025 edition is live: https://tds.s-anand.net/. Major update: a new AI-Coding section and fresh projects.

I teach TDS at the Indian Institute of Technology, Madras as part of the BS in Data Science. Anyone can audit. The course is public. You can read the content and practice assessments.

I fed the May 2025 term student feedback into The Sales Mind and asked:

What are the top non-intuitive / surprising inferences?
What are interesting observations?
What are high impact actions?

Full analysis: https://lnkd.in/gVWVqaxN: summary, outliers, and action ideas.

Most students find the course tough (or at least time-consuming), especially the Remote Online Exam (ROE).

Surprise: students who mentioned ROE time limits rated it 2.61 vs 2.33 (+12%!). Those who felt time pressure also saw more value – suggesting “desirable difficulty,” rather than frustration.

A minority even asked for tougher projects.

The main actions are faster feedback loops, automated pre-checks, mock ROEs, clear rubrics, etc.

But my two takeaways are:

Students value rigor and challenge, even if it makes the course harder.
Using LLMs to analyze student feedback is a force multiplier for instructors.

Tools in Data Science course is free for all

Thu, 01 May 2025 13:28:34 +0000

My Tools in Data Science course is now open for anyone to audit.

It’s part of the Indian Institute of Technology, Madras BS in Data Science online program. Here are some of the topics it covers in ~10 weeks:

Development Tools: uv, git, bash, llm, sqlite, spreadsheets, AI code editors
Deployment Tools: Colab, Codespaces, Docker, Vercel, ngrok, FastAPI, Ollama
LLMs: prompt engineering, RAG, embeddings, topic modeling, multi-modal, real-time, evals, self-hosting
Data Sourcing: Scraping websites and PDF with spreadsheets, Python, JavaScript and LLMs
Data Preparation: Transforming data, images and audio with spreadsheets, bash, OpenRefine, Python, and LLMs
Data Analysis: Statistical, geospatial, and network analysis with spreadsheets, Python, SQL, and LLMs
Data Visualization: Data visualization and storytelling with spreadsheets, slides, notebooks, code, and LLMs

It includes 2 projects, 7 graded assignments, and a remote online exam.

It’s a fairly tough course. Solve the first assignment to decide if you should take the course.

Course: https://tds.s-anand.net/
Code: https://github.com/sanand0/tools-in-data-science-public/

Why don't students hack exams when they can?

Fri, 22 Nov 2024 10:38:09 +0000

This year, I created a series of tests for my course at IITM and to recruit for Gramener.

The tests had 2 interesting features.

One question required them to hack the page

Write the body of the request to an OpenAI chat completion call that:

Uses model gpt-4o-mini

Has a system message: Respond in JSON

Has a user message: Generate 10 random addresses in the US

Uses structured outputs to respond with an object addresses which is an array of objects with required fields: street (string) city (string) apartment (string) .

Sets additionalProperties to false to prevent additional properties.

What is the JSON body we should send to https://api.openai.com/v1/chat/completions for this? (No need to run it or to use an API key. Just write the body of the request below.)

There's no answer box above. Figure out how to enable it. That's part of the test.

The only way to even attempt this question is to inspect the page, find the hidden input and make it visible. (This requires removing a class, an attribute, and a style - from different places.)

Here's the number of people who managed to enable the text box and answer it.

College	# students	Enabled	Answered
NIT Bhopal	144	4 (2.8%)	0 (0.0%)
CBIT	277	16 (5.8%)	0 (0.0%)
IIT Madras	693	74 (10.7%)	4 (0.6%)

A few things surprised me.

First, I think students don't inspect HTML. Less than 10% of students managed to modify the HTML page, even after being told they need to. But they know web programming. 49 students at CBIT scored full marks on the rest of the questions, which includes CSS selectors and complex JS code. Maybe editing in a browser instead of an editor is a big mental leap?

Second, almost no one could solve this problem. There are 3 ways to easily solve it.

Copy the question and relevant test cases from my exam page's JavaScript into ChatGPT and ask for an answer. (I test it and it works.)
Copy the question and structured output documentation to ChatGPT and ask for an answer. (I tested it and it works.)
Create a random JSON and just keep fixing the errors manually until it passes. (The exam gives detailed error messages like "The system message must be 'Respond in JSON'", "addresses items must be an object", etc.)

Maybe questions from a curriculum are easier to solve than questions not in a curriculum? Or is JSON schema too hard?

The exam was officially hackable

All validation was on the client side. The JS code was minified and answers are dynamically generated. But a student can set a breakpoint, see the answers, and modify their responses.

The students at NIT Bhopal and CBIT were not explicitly told that. The students at IITM were explicitly told that they could (and are welcome to) hack it.

Out of the 1,114 students who took these tests, only one student actually hacked it.

(How do I know that? No other student got full marks. This student got full marks with empty answers.)

It's probably not that difficult. My course content covers scraping pages using JavaScript using DevTools. Inspecting JS is just a step away.

I did chat with the student who hacked it, asking:

Anand: How come you didn't share the details of the hack with others?

Student: I did with a few but I am not sure whether or not they were able to figure it out still.
Most students in the program still require a lot of handholding even with basic things.
Experience from being a TA [Teaching Assistant] past term.

Why didn't they hack?

Maybe...

They don't believe me. What if hacking the exam page is considered cheating, even if explicitly allowed?
The time pressure is too much. They'd rather solve what they know than risk wasting time hacking.
It feels wrong. They'd rather answer based on their knowledge than take a shortcut.
They don't know how. Using DevTools is more sophisticated than web programming.

Issue #1 - the trust issue - is solveable. We can issue multiple official notices.

Issue #4 - capability - is not worth solving. My aim is to get students to do stuff they weren't taught.

Issue #2 & #3 - a risk-taking culture - is what I want to encourage. It might teach them to blur ethical lines and neglect fundamentals (which are bad), but it might also build adaptability, creativity, and prepare them for real-world scenarios.

Personally, I need more team members that get the job done even if they've never done it before.

Lehman Brothers interview

Sat, 09 Oct 1999 12:00:00 +0000

Lehman Brothers was recruiting Sales, Trading & Research in Tokyo, and Investment Banking in New York. If that sounds like greek, read Vault’s report on investment banking.

They seemed disappointed at the number of questions that came their way during their pre-placement presentation. There were hoping for a lot more, and agressive, questions. The people who came included Alan Cutter, Pamella, Isabella, Sarab Bhutani (all from New York), Dalip Awasthi and Sumant Gupta. They shortlisted 21 people for New York and 9 people for Tokyo. Rajesh Dalmia and I were on both shortlists.

My preparation for the interview was minimal. I went through the day’s newspapers; found out Lehman’s and IBM’s stock price (IBM because I used to work there); the Sensex, NASDAQ, Nikkei, etc. Read an article in the Economist on Central Banks (Sept ‘99). Overall, I put in about 3 hours on the previous day.

The first interview was with Dalip and Sumant. They had split themselves into 3 panels. Dalip and Sumant were for STR, while the others interviewed the remaining candidates. Sumant’s opening question was, “So you were at IIT Madras?” He was from IITM too. A year senior to me. I said, “Yeah. You were at Jamuna Hostel, right?” We went on a bit about IITM after that.

Interview

What were you doing at IBM? (We went into quite a bit of detail.)
What are your hobbies? (Again, quite a bit of detail.)
How do you value technology stocks? (This is where I scored. I said nobody knows.)
How did you find Japan in your earlier visits?

Sumant advised me to speak a little slower, and sent me to the next panel. Isabella and Sarab asked me about my long term plans, my intentions to work abroad, and whether I preferred I-Banking or STR. I said, “Equity research looks the most attractive, based on what I hear.” After a while, Sumand and Dalip called me back and asked a bit about basketball. With that, the STR interviews were closed. By 11PM, they announced that Manoj would be going to New York, and I would be working in Tokyo.

Learnings

The resume matters a lot. I filled mine with what looks ‘impressive’, and was shortlisted for both I-Banking and STR.
Lehman’s shortlisting parameters are: a good academic record, work experience in a reputed firm, and extra-curriculars – strictly in that order.
It helps to have a senior in the panel. (Manoj is from the IITs too.)
I think my work experience and prior travel to Japan worked in my favour too.

If I were preparing again for the Lehman Brothers summer interview, here’s how I’d go about it.

First, get a thin book about how to crack an interview from the library and read it, end-to-end. I say thin because it’s not worth spending more than 2-3 hours on the book, and you DO need to read it end-to-end. Of course, guides are available on the Internet, but it would be cheaper to borrow it than print it out.

Second, know thyself. That’s the most important part. Here are some questions for which you should have ready-made answers for. The rule-of-thumb, of course, is to be perfectly frank.

Why do you want to join Lehman Brothers / Investment banking / Finance?
What other companies have you applied for?
How have you been doing at IIM-B?
Tell me more about (any item on your resume).
What did you like/dislike about (any item on your resume).
What are your strengths and weaknesses (3 of each)?
Where do you see yourself 5/10/20 years down the line?

Ideally, you should get someone to interview you, ask you some of these questions. Catch your classmates, your seniors, anyone. Ask them to give you feedback on their first impression of you, and whether, if they were in that company, they would hire you. More importantly, why they wouldn’t, if at all.

Third, find out what the recruiters would be looking for. My guess is, they’re looking for someone with

Good communication skills – so speak slowly and clearly.
Confidence – so think your answer before speaking; ask for time if you need to think; relax if you’ve made a mistake.
Analytical skills and intelligence – so say “I don’t know” when you don’t, and tell them about all the analytical and intelligent things you’ve done before.

Fourth, learn a bit about the industry. Vault and Wetfeet have good industry guides. Don’t read it end-to-end. Just skim through it and get a feel of things. People haven’t gotten a feel of it after 2 months of working there, so perhaps 2 hours of skimming won’t tell you much. But it’ll get you used to the kind of words that are used there, like “80 hours a week”, “bond price”, etc.

Fifth, learn some concepts. You need to know what a stock or a share is, and what a bond is.f you’ve worked, you may like to know the share price of your former company, and why it’s there. You probably ought to have an opinion on some of the things happening in the business arena, so if you don’t have one, get one. Also make sure to look through SEO reseller pricing to pick out the best marketing strategy for your company. I’ve listed some possible questions below, and my answers, had I been asked these.

Do you think dot-coms are overvalued?: Yes. I don’t think that the productivity growth will benefit companies selling computers. I think it will benefit the users of computers. (No one knows, really, but we need an opinion and a reason.)
Are the second-phase of reforms going in the right direction?: No idea.
Why is the Euro falling, or why is the dollar rising?: No idea.
How would you value a petroleum company?: (I’m a chemical engineer, but…) I don’t know.

Well, the point, I guess, is not to have answers to all questions. The answer is to have a reason for any answer that you give. So do find out about what’s happening in the world. Read the papers. But don’t bother remembering everything. Just have an opinion on a few items of importance, with a reason.

Best of luck!

Comments

vishal 20 May 2007 7:13 am: I think this would really help ..its given nicely..& i have even copied it.. thanks for posting
nikhil 9 Oct 1999 12:00 pm: Hi,thanx for ur guidance ….
vikrant 9 Oct 1999 12:00 pm: thanks buddy … great use
Sera 9 Oct 1999 12:00 pm: I m thinking of applying for an entry level analyst position at Lehman Brothers in Japan. Your tips gave me a very insightful idea about how I should preapre for my interview. (hopefully i’ll make it to the interview.) thanks for the posting!