Y11W15WR The bullet holes that weren't there

Observational
The writing prompt

Identify three specific beliefs about success (yours or circulating in your social world) that may rest on survivorship bias, and describe what evidence would be needed to test them properly.

1Retrieval check

Q1.What did Abraham Wald tell the WWII military to do with armour?

  • AAdd it where returning planes had bullet holes
  • BAdd it where returning planes had NO bullet holes, because the planes hit there didn’t return
  • CAdd it uniformly to all planes
  • DRemove armour to reduce weight

Q2.What is the article’s counter-thread about survivorship bias?

  • AEvery absence is survivorship bias
  • BNot every absence is survivorship bias; some processes genuinely produce robust winners whose traits can be studied
  • CSuccessful people always share traits
  • DSurvivors are always lucky
Show answer key

Q1 → B. Add it where returning planes had NO bullet holes, because the planes hit there didn’t return.Wald’s insight was to reason about the missing data — the planes hit in vital areas didn’t survive to be counted.

Q2 → B. Not every absence is survivorship bias; some processes genuinely produce robust winners whose traits can be studied.Distinguishing genuine robust-winner patterns from survivor-only patterns is the actual skill — not dismissing all success analysis.

2Prompt deconstruction

Command verb
IDENTIFY and DESCRIBE — analyse specific beliefs
You pick
three specific, nameable beliefs about success
Goal
for each, separate the visible survivor-evidence from the invisible cases; propose research that would access the invisible cases
Must reference
Wald’s WWII analysis

3Pick nudge

Which beliefs will you test for missing evidence or survivorship bias?

Belief 1
e.g. ‘quit your job to pursue your passion’
Belief 2
e.g. ‘successful founders start young’
Belief 3
e.g. ‘studying X subject guarantees a good career’

4Planner — for each of your picks

Belief
Visible survivor evidence (what supports it)
#1
#2
#3

5Sentence stems

  • I noticed that ___ when ___.
  • The specific moment it stood out was ___.
  • Before paying attention, I had been assuming ___.
  • [Researcher’s] finding that ___ captures what I saw, because ___.
  • The pattern across my cases is ___.
  • What this tells me about [wider topic] is ___.

6Exemplar paragraph (not about this article)

(1) Three beliefs: (1-a) ‘Drop out to build a startup’ — the visible evidence is Zuckerberg, Gates, Jobs; the invisible evidence is the tens of thousands who dropped out and failed silently. (2) A fair test would track a matched cohort of dropouts and graduates over 10 years. (3) (1-b) ‘Elite universities produce elite careers’ — survivor evidence is the visible alumni; the test would compare admitted-and-attended students with admitted-but-declined students, as Krueger and Dale did. (4) (1-c) ‘Early waking is the habit of successful people’ — survivor evidence is morning-routine memoirs; the invisible cases are equally successful night-owls who don’t write books about their habits. (5) Wald’s lesson is that all three beliefs read the wrong holes.

What this paragraph does, move by move

  1. Names the first belief and shows both visible and invisible evidence.
  2. Proposes a fair test for the dropout belief.
  3. Tests the elite-university belief against a better comparison.
  4. Extends the survivor-bias pattern to a third belief.
  5. Links back to Wald’s analysis.