Methods you can run on a spreadsheet, a filing or a whiteboard.
Match the discount rate to the cash flow: a flow to all capital providers is discounted at the blended cost of all of them.
The discount-rate questions in a DCF interview, and any model where the cash flow and the rate have been matched carelessly.
From WACC Explained · The Finance Storyteller
Returns on a rolled futures position include the roll, so the shape of the curve matters as much as where spot goes.
Any question on commodity exposure, futures-based products or the difference between spot and investable returns.
From The Little Book of Commodity Investing · John Stephenson
A short position is a promise to deliver; whoever controls what must be delivered controls the price.
Questions on futures, short squeezes, margin or physical delivery in a markets interview.
From Trading Places · 1983
Clarify the metric, protect the guardrails, then decompose the drop by segment until it is isolated; show the process, not a guess.
Product management interviews, any analytics role, and any desk conversation that starts with a number going the wrong way.
From Google Product Manager Metrics Interview: A Worked Mock · Aakash Gupta
Name the two sides, say which one pays and why, and describe exactly how one side's growth helps the other.
Marketplace and platform pitches, product strategy questions, and the marketplace model.
From Platform Revolution · Geoffrey Parker, Marshall Van Alstyne and Sangeet Paul Choudary
Write to a model as you would brief a capable junior: the task, their role, the context they lack, and what the output should look like.
Using any model on real work, and explaining in an interview how you would get a useful answer from one.
From Prompting 101 · Anthropic
When the filings are what is in doubt, the evidence has to come from outside them.
Building a short thesis, or any diligence where the reported numbers seem too good for the business described.
From The China Hustle · 2017
Value each part a bidder is acquiring; what the bid leaves at zero is the argument against it.
Take-private analysis, fairness opinions, conglomerate valuation and any activist defence of a holding.
From Southeastern Asset Management's letter to the Dell board (February 2013) · Mason Hawkins and Staley Cates
Term premium is an estimate from a model; say which model, and treat the level as less certain than the direction.
Any rates conversation that invokes the term premium, and any question about why long yields moved while policy did not.
From Treasury Term Premia: 1961-Present · Tobias Adrian, Richard K. Crump, Benjamin Mills and Emanuel Moench, Federal Reserve Bank of New York (Liberty Street Economics)
A take-private proposal is a complete case: the public record that failed, the price, the premium, the financing and the timetable, in that order.
Take-private analysis, premium questions, and private equity interviews on how a deal is proposed.
From Elliott Management's letter to the athenahealth board proposing a take-private (May 2018) · Jesse Cohn
A seller sells certainty of closing as much as price; a bidder who offers more of it can pay less.
M&A process questions, sell-side mandates, and any private equity interview about how to win a deal.
From Barbarians at the Gate · Bryan Burrough and John Helyar
An index buys read speed with write speed and disk; add one for the query you run most and remove the ones you never use.
Database questions in engineering and data interviews, and any slow query on a desk.
From B-tree vs B+ tree in Database Systems · Hussein Nasser
Evidence about demand comes from what people have already done and paid for, not from what they say they would do.
Customer discovery, commercial due diligence, and any interview that asks how you would validate a product idea.
From The Mom Test · Rob Fitzpatrick
Spending is only growth if the return on it exceeds the cost; estimate the return under several assumptions before admiring the spend.
Any capital-intensive growth story, the AI capital expenditure debate, and valuation of a company reinvesting most of its cash flow.
From Hayden Capital's Q2 2026 letter, on the "SaaS-pocalypse" and returns on reinvestment · Fred Liu
A forecast is a story written in numbers; if a row cannot be said as a sentence about the business, it should not be in the model.
Building or defending a DCF, writing a stock pitch, or reviewing someone else's model.
From Narrative and Numbers · Aswath Damodaran
Design every retryable operation so that doing it twice has the same effect as doing it once; the network will test this for you.
System design interviews, payment and order systems, and any API that a client might retry.
From Build a Robust Payments Service Using Idempotency Keys · Arpit Bhayani
The right amount of debt minimises the blended cost of capital; the maximum a lender will provide is a different and larger number.
LBO and leveraged finance questions on how much debt a deal can carry, and corporate finance questions on capital structure.
From Session 18: Optimum Capital Structure — The Cost of Capital Approach · Aswath Damodaran (NYU Stern)
Build a margin case from countable inputs, headcount, cost per head and incremental margin on growth, so that every disagreement is about a number.
Activist situations, any margin expansion thesis, and the interview question of how you would improve a company's profitability.
From Starboard Value's letter to Autodesk shareholders on margins and board change · Jeffrey Smith
A prepayable bond gets shorter when rates fall and longer when they rise; the spread you are paid is for that asymmetry.
Fixed income, securitised products and mortgage finance interviews, and any question about why mortgage rates move with MBS rather than the policy rate.
From Mortgage-Backed Securities · Andreas Fuster, David O. Lucca and James Vickery, Federal Reserve Bank of New York (Staff Reports)
A bank's margin in a hiking cycle is decided by how slowly it reprices its deposits, measured as the deposit beta.
Bank earnings, FIG coverage, and any interview that asks how rising rates affect a bank.
From Is This Time Different: How Are Banks Performing during the Recent Interest Rate Increases Compared to 2004-2006? · Anya Kleymenova, Lori Leu and Cindy M. Vojtech, Board of Governors of the Federal Reserve System (FEDS Notes)
Schedule the uninterrupted block first; the preparation that matters cannot be done in the gaps.
Planning interview preparation, or any period where learning something structurally complex has to fit around other work.
From Deep Work · Cal Newport
A steepening is mostly term premium; a move in the two-year is half expectations, half premium. Use the rule, then say which model you trust.
A markets interview asks why long yields moved, or a desk needs a quick decomposition before the models update.
From The Treasury Tantrum of 2023 · Anthony M. Diercks and Dev Asnani, Board of Governors of the Federal Reserve System (FEDS Notes)
Write the thesis with its test attached: the variant view, the evidence, and the event that would confirm or refute it.
Writing a stock pitch, reviewing a portfolio, and any investment committee that wants to know what would change your mind.
From Greenhaven Road Capital's Q2 2026 letter, on changing how the portfolio is built · Scott Miller
Treat stock compensation as a cost of doing business; either deduct it from cash flow or count the dilution, and never ignore it twice.
Any technology company valuation, any adjusted EBITDA reconciliation, and the interview question about non-cash charges.
From Session 5: Accounting Inconsistencies · Aswath Damodaran (NYU Stern)
A synergy is a change in cash flow, growth or risk; value it as one, and only then compare it with the premium being paid.
M&A interviews that ask how to value synergies, and any deal where the premium is justified by them.
From Session 12: Acquisition Ornaments — Synergy, Control & Complexity · Aswath Damodaran (NYU Stern)
Check what share of the value is terminal and what multiple the terminal assumptions imply; those two checks catch most broken DCFs.
Any DCF review, any interview follow-up on the terminal growth rate, and any model where the answer seems too sensitive to the last year.
From Session 9: Terminal Value · Aswath Damodaran (NYU Stern)
Judge an acquisition by what happened to the acquired brand's share of its market afterwards; the number is public and hard to argue with.
Post-deal assessment, consumer and brand coverage, and any activist case built on competitive evidence rather than financial engineering.
From Trian's July 2017 letter to Procter & Gamble shareholders · Trian Fund Management
A long window degrades before it fills; curate and order what goes in rather than relying on size.
Designing any system that feeds documents to a model, and explaining why a model missed something that was in its context.
From Why LLMs Get Dumb (Context Windows Explained) · NetworkChuck
Find the subproblem and the recurrence first; the implementation is mechanical once the structure is clear.
Coding interviews, and any problem whose difficulty is in the decomposition.
From 5 Simple Steps for Solving Dynamic Programming Problems · Reducible
A short thesis is a public claim set against a fact the company does not control, with the arithmetic that joins them shown.
Short pitches, forensic work, and any thesis that depends on reported figures being false.
From Muddy Waters' initiating report on Sino-Forest · Muddy Waters Research
An inverted curve is the market expecting cuts; read the near-term forward spread, because the long spread is diluted by the term premium.
Rates, macro and sales and trading interviews, and any time a headline says the curve has inverted.
From (Don't Fear) The Yield Curve · Eric Engstrom and Steve Sharpe, Board of Governors of the Federal Reserve System (FEDS Notes)
Read the notes before the numbers; the disclosure that matters is usually there and usually ignored.
Any model review, any quality of earnings exercise, and any short thesis.
From The Signs Were There · Tim Steer
Seniority is a queue for losses; the thickness of the slices beneath you is your protection.
Any structured credit, securitisation or capital structure question, in an interview or on the desk.
From The Big Short · 2015
Publish the method for intrinsic value, then let it decide: buy back below it, issue above it, and keep the multiple consistent so the method cannot flatter.
Valuing a holding company or an insurer with an investment portfolio, and any discussion of how management should decide on buybacks.
From Markel Group's 2023 letter to business partners · Thomas Gayner
A buyback creates value only with funds to spare and a price well below intrinsic value; above that price the same action destroys it.
Any capital allocation question, any company announcing a buyback, and private equity interviews on value creation.
From Berkshire Hathaway's 2011 letter to shareholders · Warren Buffett
Build the test set before the feature, measure every change against it, and keep a person in the loop where the metric cannot be trusted.
Any AI product discussion, any system design that includes a model, and the question of how you know an AI feature works.
From How to Systematically Set Up LLM Evals · Dave Ebbelaar
Growth ties up cash in receivables and inventory, so model the working capital a business needs before trusting its profit.
Three-statement questions, cash flow forecasting, and any growth company whose profit and cash are diverging.
From Working Capital Explained · The Finance Storyteller