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Taught by Paul Montero, founder and instructor

Make better decisions with data.
Catch fraud before it costs you.

Eight self-paced courses that take you from a messy spreadsheet to a fraud model in production. Built on realistic Indian business data, priced in rupees, with a GST invoice on every purchase.

Browse coursesRead a free chapter
  • 8 coursesBeginner to advanced
  • Self-pacedAccess for at least 12 months
  • Pay by UPICards, netbanking, wallets too
  • 7-day refundNo questions asked

New here?

Choose your path

Each path is a sequence. Start where your work is today and stop when you have what you need.

The courses

Eight modules, in the order they build on each other

Every course lists its chapters and opens one of them free, so you can judge the teaching before you pay.

Filter by level or topic

Try before you buy

Read a chapter first

Not a trailer. A full chapter from each course, exactly as paying students read it.

  • 1Data Analysis Foundations

    What a good analysis looks like

    “Most analysis at work fails before any number is computed. Someone is handed an export, opens it, and starts making charts. Two hours later there are eleven charts and no answer. The fix is …

    Read the chapter

  • 6Fraud Analytics

    How fraud shows up in data

    “Fraud is a story about incentives, but it leaves a trail in tables. A stolen card is used fast, on new devices, for goods that can be resold, before the real owner notices. An account takeov…

    Read the chapter

  • 7Machine Learning for Fraud Detection

    Labels

    “A fraud model learns from examples of fraud, and the examples are worse than they look. A chargeback arrives 30 to 120 days after the transaction, so the most recent months of data have almo…

    Read the chapter

All 8 free chapters

Membership

Every course for ₹800 a month

One UPI AutoPay mandate. Access to all eight courses and anything added later, for as long as you stay. Cancel from any email, any time.

  • All courses

    Every module, every chapter, every dataset.

  • New courses included

    Anything published while you are a member.

  • Cancel any time

    Access runs to the end of the paid month. No partial-month refunds, no arguments.

See mandate terms and startOr pay once: all-access ₹12,000

What you are authorising

Amount
₹800 per month, incl. GST
Frequency
Monthly, same date
Mandate cap
₹800
Cancel
Link in every email, or in your UPI app

Your instructor

Paul Montero

Founder and instructor

Paul has spent his career in fraud prevention and payments risk, working across many markets in Latin America, Europe, and Asia, on both the payment-provider and the merchant side.

For the last several years his focus has been Indian payments, one of the most complex fraud environments anywhere: UPI, cards, wallets, and lending, each with its own fraud patterns, data, and regulator. The courses on Ledgerline are the analysis habits, queries, and models that work came out of.

Every course here comes from work I have done on real data: transaction tables, dispute files, onboarding documents, and the dashboards teams argue about on Monday mornings. The exercises use datasets built to look like that data, with the mess left in.

More about how the courses are made

Questions

Before you buy

Do I need to know how to code?
Courses 1, 2, 3, and 5 need no code beyond SQL, which course 2 teaches from zero. Courses 4, 7, and 8 use Python and start from the basics. Course 6 works in SQL with an optional Python track.
How do I get access after paying?
An email with your access link and GST invoice is sent as soon as payment is confirmed, normally within minutes. If it has not arrived in 30 minutes, see the Delivery Policy for what to do.
What if the course is not for me?
Ask for a refund within 7 days of purchase. You do not need to give a reason. Money goes back the way it came within 7 working days.
Is there a certificate?
No. These courses are judged by what you can do afterwards, and the capstone in each course is built to be shown to a manager or put in a portfolio. We do not issue certificates and do not claim any third-party accreditation.
Will this get me a job or a promotion?
We do not promise outcomes of any kind. The courses teach skills that risk, analytics, and operations teams use every day. What you do with them is yours.
Which payment methods work?
UPI (any app), debit and credit cards including RuPay, netbanking, and wallets. Prices are in INR and include 18% GST; the invoice shows the split for your state.