Start here New? Read these first.
01 · Trading & Indicators
How to Backtest a Trading Strategy
Test an idea properly — without fooling yourself.
03 · Investing & Wealth Building
How to Build a 3-Fund Portfolio
A complete, boring, durable place to start.
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Latest research
What Moves Currency Prices? Interest Rates, Inflation, and Central Banks
What actually moves currency prices, explained plainly: interest-rate differentials and the carry trade, inflation and purchasing power, central-bank policy and intervention, and…
What Is Overfitting in Backtesting (And How to Avoid It)
Overfitting is why a beautiful backtest and a losing strategy are so often the same thing. What overfitting actually is, why searching…
What Is Inflation, Really? A Plain-English Breakdown
Inflation isn’t just ‘stuff is expensive right now.’ This plain-English guide explains what inflation really is, how CPI and PCE measure it,…
What Is APR vs APY? The Difference That Costs You Thousands
APR is what you pay to borrow; APY is what you earn to save — and the crucial catch is that APY…
What Are Fractional Shares? How to Invest When You Can’t Afford a Full Share
A fractional share lets you buy part of a share by the dollar — so $10 can buy into a $400 fund.…
Walk-Forward Analysis: Testing a Strategy Like a Quant
Walk-forward analysis re-optimizes a strategy on a rolling window and tests it once on the next unseen slice, over and over. Here…
VTI vs VOO: Which Benchmark ETF Should You Hold for Life?
VTI vs VOO: they share the same issuer, the same 0.03% fee, and about 82% of the same holdings. Here’s the one…
The Difference Between Trading and Investing (And Why It Matters)
Trading and investing look the same from the outside but are two different activities. A plain-English guide to how they differ in…
Total Market vs S&P 500 Index Funds: Does the Difference Matter?
A total-market index fund holds ~3,600+ US stocks; an S&P 500 fund holds ~500 large caps. They share most of their weight…