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AdvancedStock Alerts + Tools0:45Quant

Two Ways the Data Lies

Survivorship removes the failures from history and look-ahead gives you information you could not have had. Both inflate results quietly.

0:45 · 6 scenes

This lesson is part of a Stock Alerts + Tools plan.

What the lesson covers

  1. 0:00Two data problems inflate almost every naive backtest.
  2. 0:05Survivorship. Today's index members exclude every company that failed along the way.
  3. 0:14Look-ahead. Using a figure on a date before it was actually published. Earnings are the usual case.
  4. 0:23Why they are hard to spot. Neither produces an error. Both simply produce a better-looking result.
  5. 0:32The fix. Point-in-time data, including delisted companies, with real publication dates.
  6. 0:40Ask what is missing from the data, and when each figure was known.
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Educational content only. MadStockAlerts provides market commentary, research, and educational content. It is not personalized investment advice, and nothing here is a recommendation to buy or sell any security. Trading and investing involve substantial risk, including loss of capital. See the Risk Disclosure and Customer Agreement.
Educational content only. MadStockAlerts provides market commentary, research, and educational content. It is not personalized investment advice, and nothing here is a recommendation to buy or sell any security. Trading and investing involve substantial risk, including loss of capital. See the Risk Disclosure and Customer Agreement.
Two Ways the Data Lies — MAD Academy Training Video · MadStockAlerts