Descriptors Before Performance
A tear sheet leads with performance, and a trained reader ignores that page until the descriptors are established. A Sharpe ratio is not a property of a strategy; it is a property of a strategy on a universe, at a turnover, under cost assumptions, over a span. Change any of those and the same number means something different.
The descriptors that gate everything
Universe. What is tradable, how it was defined, and as of when (the survivorship question from section 3). Small caps and illiquid names inflate paper alpha because that is where prices are noisiest and costs are largest.
Turnover and holding period. Turnover converts cost assumptions into performance: a strategy turning over 50 times a year lives or dies on basis points of slippage, while a monthly rebalancer barely notices. Holding period also determines the effective sample size of the track record, since a 10-year backtest of a yearly signal contains ten bets.
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