The Livermore discussion contrasts remembered brilliance with omitted failures. Niederhoffer then argues for evaluating, testing and analyzing seemingly sensible theories rather than accepting them on the strength of a story.
Translate the maxim
“Successful traders do X” has hidden questions: which traders, what counts as success, how X is identified and whether unsuccessful traders also do it. A fair test needs both the favored examples and a relevant comparison group.
Worked example
If ten famous winners kept journals, that is interesting. If almost every unsuccessful participant also kept one, the observation alone does not show that journaling explains success.
Case connection
Remembering winners leaves out the comparison group. A success maxim needs records of less successful participants too.
SPIVA: include the missing funds
Source-grounded facts
SPIVA evaluates the whole starting opportunity set, including funds that disappear, to address survivorship bias.
Context
Fund-performance comparisons can quietly change when unsuccessful funds close or merge. SPIVA’s published methodology addresses that problem by retaining the starting opportunity set.
Outcome
Including disappeared funds reduces survivorship bias. It does not make every benchmark choice perfect; it makes the population being evaluated more explicit and harder to improve by hindsight.
- The comparison identifies the eligible fund universe at the beginning of the evaluation period.
- It accounts for funds that disappear rather than comparing only those still present at the end.
- It also uses relevant benchmarks and reports results over specified horizons.
Case analysis
A story about successful people can hide the unsuccessful people who behaved similarly. Use the starting fund universe as a model for a fair comparison: specify the group before its performance is known. A maxim becomes more credible only if it survives that broader comparison, not because the selected winners are famous.
Try it
Choose a trading maxim. Write its hidden denominator and an observation that would weaken it.