Random-sign control

Not a strategy — a test of the testing. It runs identical machinery but decides which way to bet on each asset by coin flip. If this scored well, nothing else on this site could be believed.

Conclusion: Control

A benchmark, not a candidate. Held continuously it returned 0.3% a year at 12.1% volatility, with a worst fall of 68.5% over 558 months. Strategies are measured against this.

Figure 1 · Growth of $1

1980–2026 · net of 15bp round-trip costs
What one dollar became, after costs: $1.15 by 2026. Shown against S&P 500, rebased to the same starting dollar.
Return for risk
0.03
range (0.23) to 0.28
Ann. return
0.3%
volatility 12.1%
Max drawdown
68.5%
over 558 months
Beats the search
0.0%
chance, after correction

Method

Hypothesis

Calibration. Should score zero.

Rule

UNIVERSE = the high-conviction set
function positions(bar):
# signs drawn once from a fixed seed and never revisited
for symbol in UNIVERSE:
w[symbol] = coin_flip(seed, symbol) / vol_36m(symbol, bar.prev)
size = clip(zscore(feature(soi_3m), expanding) / 2, -1, 1)
return w * size
# ── execution ────────────────────────────────────────────────────────
COST_PER_TRADE = 15 bps of the notional that changes hands
function on_bar(bar, book):
if not bar.is_month_end:
return # decisions are made monthly only
target = positions(bar) # the rule above
target = scale_to_gross(target, 1.0)
rebalance(book, target, bar)
function scale_to_gross(w, limit):
gross = sum(abs(w)) # total capital at work
if gross == 0:
return w # flat is a valid target
return w * limit / gross # leverage fixed, never implicit
function rebalance(book, target, bar):
for symbol in union(book.symbols, target.symbols):
delta = target[symbol] - book.weight(symbol)
if delta > 0:
buy(symbol, delta, fill = next_bar.close)
else if delta < 0:
sell(symbol, -delta, fill = next_bar.close)
book.charge(COST_PER_TRADE * abs(delta))
# Orders are filled at the next month's close, never the one the decision
# was made on. There is no stop_loss(), take_profit(), limit order or
# position cap: a holding changes only when positions() returns a
# different target at the next month end.

Analysis

Purpose

Every claim in this anthology depends on the evaluation harness being capable of returning nothing. This strategy runs the identical construction — same universe, same inverse-volatility weighting, same costs, same execution lag — with exposure signs drawn once at random.

It returns 0.025. That is what licenses reading any other number here.

Evaluation

Table 1 · Performance

1980-01 – 2026-06 · 558 months, 558 invested
MeasureValue
Annualised return0.3%
Annualised volatility12.1%
Return for risk taken0.03
95% range(0.23) to 0.28
t-statistic0.17
Maximum drawdown68.5%
Hit rate50.2%
Annual turnover3.60×
Return skew0.27
Return kurtosis6.67
The range is measured by resampling the history in blocks, so runs of good and bad months stay intact.

Table 2 · Robustness

DiagnosticValueReads asBadOkayYayHmm
Design half (pre-2015)0.04return for risk≤ 00 – 0.40≥ 0.40
Holdout half (2015+)(0.11)return for risk≤ 00 – 0.40≥ 0.40
Top-5-month share of profit506.1%how much rode on a few months — lower is better≥ 40%25 – 40%< 25%
Top-2-year share of profit311.4%concentration
Distinct trading episodes1how many independent runs this really is< 5050 – 100≥ 100
Chance the edge is real56.7%non-normality corrected
Chance it beats the whole search0.0%chance of beating the whole search by luck
bad/ok boundary is the pre-registered criterion · ok/good is a margin above it, not a criterion · blank where none was registered
The last row asks whether the result would stand out from the hundred-odd ideas tried here, rather than being judged alone.

Table 3 · Net return by calendar year

after costs
+25%-25%
YearNet return
19801.9%
1981(3.4%)
1982(5.8%)
19836.6%
1984(15.5%)
1985(20.1%)
19866.6%
198718.4%
198824.8%
19890.6%
199013.6%
199118.5%
1992(8.2%)
199318.1%
1994(15.9%)
1995(3.0%)
1996(1.9%)
1997(4.2%)
1998(14.8%)
1999(7.2%)
2000(16.3%)
200113.4%
20022.3%
2003(5.6%)
200413.4%
20051.6%
20060.9%
20070.1%
20088.1%
20091.9%
2010(4.9%)
2011(0.7%)
20122.1%
20130.3%
2014(7.1%)
2015(5.8%)
20162.2%
2017(1.4%)
2018(0.3%)
2019(0.3%)
2020(2.9%)
2021(1.2%)
2022(1.0%)
20234.3%
2024(0.0%)
2025(1.1%)
20262.3%

Table 4 · Concentration detail

MeasureValue
Best years1988:+25%, 1991:+19%, 1987:+18%
Worst year1985:-20%

Reference

Instruments

last price and one-month change, live from Yahoo Finance
SymbolNotes
GNC.AXGrainCorp — listed on ASX, in AUD.
ELD.AXElders — listed on ASX, in AUD.
NUF.AXNufarm — listed on ASX, in AUD.
AAC.AXAustralian Agricultural Company — listed on ASX, in AUD.
BALRAMCHIN.NSNot in the instrument table.
TRIVENI.NSTriveni Engineering & Industries — listed on NSE, in INR.
DHAMPURSUG.NSNot in the instrument table.
COROMANDEL.NSNot in the instrument table.
CHAMBLFERT.NSNot in the instrument table.
M&M.NSMahindra & Mahindra — listed on NSE, in INR.
ESCORTS.NSEscorts Kubota — listed on NSE, in INR.
ZW=FChicago SRW Wheat — continuous futures on CBOT, quoted in US cents.
ZM=FSoybean Meal — continuous futures on CBOT, in USD.
ZR=FRough Rice — continuous futures on CBOT, in USD.
list truncated in the source record

Sample

1980-01 – 2026-06 · 558 months

Sources

NOAA Physical Sciences Laboratory. Climate indices. ONI, Niño 3.4, MEI v2, DMI, PDO, AMO, TNA, QBO, solar flux. psl.noaa.gov/data/climateindices/list
Queensland Department of Agriculture and Fisheries. Southern Oscillation Index. The Long Paddock. Monthly, 1876–. www.longpaddock.qld.gov.au/soi/soi-data-files
Yahoo Finance. Historical market prices. Adjusted close, month-end. Retrieved with yfinance. finance.yahoo.com

Revision history

RevStageStatusChange
01DraftDirection and criteria fixed before the experiment ran
02TestedControlBenchmark, not scored against the criteria
algorithmic-trading-anthology-july-2026-random-sign-control | d/rksci