Investing
A high backtest Sharpe ratio proves little: what real validation requires
Reported Sharpe ratios inflate with every unreported trial, and the corrections that account for this are arithmetic, not opinion.
August 28, 2026
UZU News — MARKETS · INVESTING
Latest News
Finance News
SEC settles its first AI-washing cases for a combined $400,000
Two advisers paid penalties in March 2024 for overstating their use of machine learning, and the orders turn on the gap between claimed and actual model use.
August 24, 2026
Analysis
What does out-of-sample mean in a forecasting paper?
Out-of-sample scoring is the only published test that approximates live trading, and most papers still manage to overstate it.
August 26, 2026
Markets
Markets
What is 'probability of backtest overfitting,' and how is it actually measured?
A diagnostic built to answer one question a good Sharpe ratio can't: how much of a backtested strategy's performance is signal, and how much is the number of…
August 15, 2026
Markets
Anatomy of a bid-ask spread: where the pennies go
A spread decomposes into processing cost, inventory risk and adverse selection — and each component behaves differently when markets speed up.
July 23, 2026
Markets
What does trading volume measure, and what doesn't it tell you?
Volume counts transactions, not conviction — and the modern tape's count includes flows that carry no opinion at all.
June 30, 2026
Investing
Investing
How many signals were tested before this one worked?
Multiple testing turns luck into apparent skill. What the correction procedures control, the hurdles the replication literature settled on, and what a corrected…
August 21, 2026
Investing
What a fund's turnover ratio tells you, and what it doesn't
Turnover measures the pace of trading in the portfolio — a fact with predictable cost and tax consequences, not a verdict on skill.
July 27, 2026
Economy
Economy
The Backtest Trap: Why a Great Historical Track Record Doesn't Prove a Forecasting Model Works
AI-driven trading and forecasting tools are often sold on the strength of impressive backtested results. Here is the mechanism by which those results can be…
August 12, 2026
Economy
BEA's first read on Q2 2026: real GDP grew 1.5 percent
The advance estimate prints 1.5 percent annualized growth after 1.6 percent in Q1 — and by design it is an estimate of an estimate.
August 1, 2026
Analysis
Analysis
What replaced the guidance that has governed bank models since 2011?
Federal regulators rewrote model risk management guidance in April 2026, keeping the same validation core built around conceptual soundness and outcomes…
August 19, 2026
Analysis
The Fed's stress tests changed shape: what averaging does to comparability
The 2026 results — 32 banks, $708 billion in projected losses — arrive inside a methodology overhaul that trades year-to-year volatility for smoother…
August 5, 2026
Finance News
Finance News
Every backtest is one of many: what the trial count does to measured performance
Ten trials are enough to yield an in-sample Sharpe ratio of 1.57 from strategies with zero expected out-of-sample performance. What validation, multiple-testing…
August 17, 2026
Finance News
July FOMC holds again — this time with three members voting to raise
The 9-3 vote on July 29, 2026 kept the range at 3.50 to 3.75 percent, the year's first hawkish dissents arriving after a unanimous June.
August 10, 2026
Don't Miss
Analysis
How to evaluate an alternative data vendor: a working checklist
Point-in-time integrity, provenance, history depth and decay tests — the questions that separate a signal from a spreadsheet.
July 14, 2026
Markets
Implied volatility is a price, realized volatility is a measurement
The two numbers answer different questions, and the measurable gap between them is a premium, not a forecast.
December 30, 2025
Finance News
Stress test 2026: 32 banks absorb $708 billion in projected losses
The Fed's June 24 results show a 1.6-point CET1 drawdown under the severely adverse scenario — the first cycle read under the new averaging framework.
June 25, 2026
Investing
How does the wash-sale rule actually work?
A 61-day window, a substantially identical security, and a deferred loss — the mechanics as the IRS writes them.
February 18, 2026