Bond Convexity Explained: Why Duration Isn’t Enough
Duration is a tangent line; convexity is the curvature. Here is the formula, a worked 10-year Treasury example, and why MBS has negative convexity.
investing basics
Investment Grade vs High Yield Bonds: A Complete Guide
How investment grade and high yield bonds differ: rating cutoffs, spreads, default rates, recovery rates, and the math behind credit risk.
Mortgage-Backed Securities Explained: Pass-Throughs & CMOs
How an MBS actually works: who issues it, how cash flows from borrower to investor, why CMOs exist, and the prepayment risk every investor must understand.
The Rule of 40 Explained: How SaaS Stocks Are Valued
How the Rule of 40 actually works: the formula, a worked example using Snowflake’s Q1 FY27, common pitfalls, and the newer Rule of X.
Margin and Margin Calls: How Borrowing to Buy Stocks Works
How buying on margin works: Reg T’s 50% rule, FINRA’s 25% maintenance minimum, what triggers a margin call, and why brokers can liquidate without notice.
S&P 500 Inclusion: What Really Happens When a Stock Joins
How a stock actually gets added to the S&P 500, what the historical “index effect” was, and why recent research finds that pop has largely vanished.
The VIX Explained: How Wall Street’s Fear Gauge Works
What the VIX really measures, how it’s built from SPX options, why VIX ETPs like VXX lose money over time, and the common mistakes traders make.
Sharpe Ratio Explained: Measuring Risk-Adjusted Returns
How the Sharpe ratio works: the formula, a worked example, common pitfalls, and why William Sharpe himself warned against trusting a single number.
Secondary Stock Offerings: Dilution, ATMs, and Greenshoes
How public companies issue new shares after their IPO, why the stock usually falls on the announcement, and what ATM offerings and greenshoes really do.
TIPS Explained: How Inflation-Protected Treasuries Work
How Treasury Inflation-Protected Securities work — principal adjustment, real yield, breakeven inflation, taxes, and where TIPS fit in a portfolio.