Quantmodel · Strategy research

Glenn's Paired Switching Strategy

Glenn's Paired Switching Strategy receives a research grade of F (composite 49 / 100) on Paper-to-Profit robustness tests run against published monthly ours versus SPY. On these tests the published path does not currently support a constructive allocation case.

F score 49 AS 756.0 months 1963-08 → 2026-07

Factor grades

Statistical edge · 20% F 34
Bootstrap vs SPY · 18% F 21
Alpha decay · 16% F 17
Overfit / stability · 16% A 87
Cost robustness · 15% A 96
Regime / stress · 15% F 51

Published CAGR 10.34% / Sharpe 0.85 / max DD -30.2% over 756 months. Those headline stats are context only; the grade is the robustness tests above.

Assessment

Statistical edge

The path makes money vs zero (p=0.000) but is not a significant edge versus SPY (p=0.918, excess -0.02% per month). Same failure mode as a strategy that only rides beta.

Bootstrap versus SPY

Block bootstrap of consecutive months (400 paths): P(beat SPY) over 6.0 months is 36%; over 24.0 months is 36%. This is the Paper-to-Profit 'realistic path' test, not a reshuffled iid sample.

Alpha decay

15% of 12-month OLS windows have a significantly positive slope and 47% are significantly negative. Terminal strategy/SPY wealth ratio is 1.01. A steadily rising log-relative-wealth line is the decay test from the tutorial; a late collapse is a warning.

Overfit / stability

70/30 OOS/IS Sharpe ratio is 0.93; second/first-half Sharpe ratio is 1.07. Walk-forward parameter search is not estimable on a frozen catalog snapshot; this split is the overfit proxy. Return-space noise did not halve Sharpe on the tested grid.

Transaction costs

Average daily turnover is 1.151%. Additional one-way costs through 24 bps did not cut Sharpe in half. That is the tutorial's cost-robust case.

Regimes and crises

The path beats SPY in 19% of classified months (4.0/7.0 regimes). In bear/strong-bear/vol-down months it beats SPY 100% of the time. Crisis windows: Dot-com bust: strategy 6.0% vs SPY -38.4%; Global Financial Crisis: strategy 7.0% vs SPY -46.0%; COVID crash: strategy -2.1% vs SPY -19.4%; 2022 inflation shock: strategy -28.1% vs SPY -23.9%.

Limitations

Tests use published monthly ours, already lagged one bar in the engine, versus SPY. t-tests assume roughly comparable monthly means; Wilcoxon is shown as a non-normal check. Bootstrap paths are overlapping consecutive months (not iid reshuffles). Noise is added to monthly returns, not to OHLC, because this producer does not rerun backtests. Walk-forward parameter optimization, SPA, and PBO are not estimable without a trial ledger. Fee drag is extra one-way bps on catalog average daily turnover, on top of the published costed path.

Edge tests

Test Statistic p-value Significant?
t-test vs zero 6.77 0.0000 yes
t-test vs SPY (paired) -0.10 0.9178 no
Wilcoxon vs zero 185063.0 0.0000 p<0.05

Part 1: a strategy that only beats zero but not SPY has no statistically significant edge versus the market.

Monthly return distributions

Strategy versus SPY on the shared window. Input to the t-tests above.

Block bootstrap — 6 months

400 overlapping consecutive-month paths. P(beat SPY) = 36% . Fan is p10 / p50 / p90 of terminal wealth from $1.

Block bootstrap — 24 months

Same construction at a two-year horizon. P(beat SPY) = 36% .

Bootstrap excess CDF

Sorted 24-month strategy minus SPY terminal wealth. Fraction above zero is P(beat SPY).

Relative wealth versus SPY

Strategy equity divided by SPY equity. A rising line is persistent outperformance; a late roll-over is decay.

Rolling OLS slope of log relative wealth

12-month window on ln(strategy/SPY). Positive significant slopes are the tutorial's "edge is still there" test.

70/30 chronological split

Train through 2007-09. OOS/IS Sharpe ratio 0.93 . Walk-forward parameter search is not estimable here; this is the overfit proxy.

Transaction-cost sensitivity

Extra one-way bps applied to average daily turnover, on top of the published (~10 bps) path. Half-Sharpe at beyond 24 bps.

Return-space noise

Gaussian noise scaled by 12-month rolling vol. Not an OHLC re-backtest. Critical multiplier (Sharpe halves): not reached.

SPY regimes

Seven trend/vol states on a 12-month SPY window. Mean monthly return of strategy versus SPY in each state.

RegimeMonthsStrategy meanSPY meanBeats SPY?
Strong bull 161.0 1.19% 1.74% no
Bull 96.0 0.66% 0.83% no
Sideways 15.0 -0.73% -2.32% yes
Bear 11.0 -0.27% -1.84% yes
Strong bear 3.0 0.88% -7.47% yes
Volatility up 63.0 1.35% 1.98% no
Volatility down 48.0 0.80% -0.64% yes

Named crisis windows

EpisodeStatusStrategySPY
Dot-com bust ok 6.0% -38.4%
Global Financial Crisis ok 7.0% -46.0%
COVID crash ok -2.1% -19.4%
2022 inflation shock ok -28.1% -23.9%

Growth of $1

Published path versus SPY, 60/40 when present, and a leave-one-out catalog mix. Context only — not a scoring factor.

Drawdown

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