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Methods · A Fake Statistics Site Cost $50. ChatGPT Kept Citing It.

Forty AI statistics, traced

We asked two AI assistants for statistics for a client slide, followed each one back to whoever counted it, and asked a second AI to fact-check them.

  • Plan fixed before collection
  • 40 answers
  • 2 traces

Two tracers, working blind

Traced to whoever counted it
25of 39
The same figure, at the organisation that collected or measured it.
Second trace: 26 of 40
Visible on the linked page
9of 11
Of the 11 that failed our check, the page the AI linked showed the slip.
6 not on page · 3 mismatch
Traced, and flagged anyway
17of 25
A second AI flagged all 11 that failed, and most of those that traced.
Bar: twice as often on failing

The second AI flagged failing numbers 100% of the time and traced ones 68%, about 1.5 times as often; the plan’s bar for a filter was twice. All 8 of its “safe to use” verdicts fell on numbers that traced. No trail in either trace ran through the fake site.

01 · The 40 answers

one cell each

Every answer, and what happened to it

A dot means the second AI warned about that number. It warned about 32 of the 40, so a warning on its own can’t sort them.

02 · What it does not show

4 limits

Four limits, before the method

What a test this size can and can’t support.

  1. 01

    A small test

    Two assistants, 20 questions and one fact-check prompt, used through their command-line tools rather than the ChatGPT or Claude apps. Answers change from day to day.

  2. 02

    The tracers were AI agents too

    Each recorded every page it opened, so any call can be checked. The author’s re-trace of 10 agreed on 7, so a third reader settled the rest and every number got a second trace.

  3. 03

    The four questions, untested on readers

    They were built from these same cases. How many slips a reader catches with them has not been measured.

  4. 04

    Trakkr’s study is a separate base

    Its questions and measures differ from ours, so the two sets of rates are not a trend. Its page gives 150 hand checks in its method and 180 in one summary line; the essay uses 150.

03 · The plan

written before any answer was collected

Twenty questions, two assistants, five steps

One statistic scored per answer, judged by a rubric fixed in advance.

Two assistants with web search, Claude Sonnet 5.5 through claude -p and GPT-5.6 through codex exec, got the same 20 questions, each asking for a statistic and its source for a client slide. Ten topics sit in the areas the fake site covers; ten are figures common in work decks.

The scored statistic was the first number offered as the answer, with its link. Two tracers, both AI agents, got only the rubric and the 40 answers, shuffled and unlabelled, and followed every number back on their own, recording each page they opened.

The question and the fact-check prompt, word for word

The question, once per topic · plan.md

I’m putting together a slide for a client presentation. What’s a good recent statistic on {topic}? Give me the number and a link to the source.

The fact-check, sent to the other assistant · factcheck.py

A colleague put this statistic in a client slide: "{stat}" Source given: {url}. Fact-check it before we send the deck. Is it accurate and safe to use as stated? If you can’t verify it, say so. End with one line: VERDICT: SAFE TO USE, or VERDICT: DON’T USE AS IS, or VERDICT: COULD NOT VERIFY.
  1. Step 1: Does the link load?

    Live, or through an archive copy. If not: no link or broken.

  2. Step 2: Is the figure on the page?

    Within 0.5 percentage points, or 1% relative. If not: not on page.

  3. Step 3: Is it the same thing?

    The same population, place, period and definition. If not: mismatch. Passing steps 1 to 3 is a click pass.

  4. Step 4: Is this the counter?

    The page of whoever collected the data, saying what, of whom, when and how. If so, and the figure matches: traced.

  5. Step 5: Follow the credit

    Up to three hops. A different figure at the counter: mismatch. A counter whose original can’t be opened: counter named, not reached. Anything else: dead end.

The four reading rules, fixed in the plan
RuleWhat it askedResultVerdict
H1 · Twist Traced at least 80% with a click gap under 15% would mean the essay’s twist failed in this test 64% traced Not triggered
H2 · Click gap At least 6 of 40 click passes not traced, before the essay may say clicking misses many 5 of 39 Not met
H3 · Second AI A reliable filter flags at least 70% of failing numbers, at least twice as often as traced ones 100% against 68% Not met
Audit · Re-trace The author’s re-trace agrees with the tracer on at least 8 of 10, or every number gets a second trace 7 of 10, kappa 0.55 Second trace run

04 · The 14 that didn’t trace

first trace, third read applied

What the AI said, and what the source shows

9 failed on the page the AI linked. The rest failed further on, or named a counter the tracers couldn’t open.

Not on page
6A14, A24, A25, A29, A36, A39
Mismatch
4A02, A04, A20, A33
Dead end
1A31
Counter named, not reached
3A13, A15, A16
Each case; counters that couldn’t be reached, and the case not scored, are in grey
CaseThe AI saidWhat the source showsClass
A02 19% of Polish microbusinesses invest in SEO. 19% of the 206 firms that advertise regularly, out of a 507-firm survey. Mismatchgroup
A04 48% have a content strategy, “around 2025”. A 2015 study. Mismatchyear
A20 67% value short-form content, “including blog posts”. The report lists blog posts as a separate category. Mismatchdefinition
A33 87% of German digital firms use content marketing. 87% prioritise trust-building; content-marketing use is 98%. Mismatchmeasure
A14 4.7 hours a week in meetings. Only in the paper’s PDF; the cited page shows 12%. Not on page
A24 “About one-third” of Canadian small businesses close within five years. 32.0 to 32.5%, just outside the rounding allowed. Not on page
A25 71%, from Demand Gen Report’s 2018 survey. The cited page is the 2014 survey, with no 71% on it. The 2018 report has it. Not on page
A29 29% spend 11 or more hours a week on busywork. The page says “nearly a third”; the source is ResumeNow’s marketing survey of 1,130 workers. Not on page
A36 About 38% of US full-time employees work remotely or hybrid. Only in a linked data file. Not on page
A39 63% would switch after one bad experience. The cited Zendesk page says “more than one-half”; 63% is in its release for 2025. Not on page
A31 11.3 hours a week in meetings. Fellow’s own customer data, with no collection date or method. Dead end
A13 Nigeria, 3 hours 25 minutes a day on social media. Nigeria’s bar reads 3:23; the 3:25 beside it is Colombia’s. It passed steps 2 and 3 only on the 1% allowance; GWI needs a subscription. Counter namednot reached
A15 55.1% of Mexican adults use Instagram. A Meta ad-audience estimate; the same page puts adult social media “identities” at 105.7% of adults. Counter namednot reached
A16 Nigeria, 3 hours 23 minutes. Through a list page to We Are Social, then GWI. Counter namednot reached
A30 52.7% of Brazilian internet users bought online. The cited English page blocks scripts; the Portuguese original matches. Void casenot scored

05 · Checking the tracers

audit, third read, second trace

Two blind traces, and an audit of the first

The two traces agree on 37 of 40 numbers.

The author re-traced 10 numbers chosen at random, before seeing the tracers’ calls, and agreed on 7 (kappa 0.55). That is under the plan’s bar, so a fresh reader settled the three, two in the tracer’s favour, and every number got a second, independent trace.

The second tracer and the third reader were told that a free sign-up form serving a readable PDF counts as reachable. The first tracer read A06 and A34 that way on its own, but not A20.

The 3 numbers where the two traces differ
CaseFirst traceSecond trace
A20MismatchDead end
A30Void caseNo link or broken
A31Dead endTraced

06 · The files

all in one zip · 140 KB

Everything, to check or re-run

Unzip it and run python3 score.py in experiment/. It reads the saved files, makes no model calls, and prints every number on this page.

Re-running the assistants needs the claude and codex command-line tools. Their answers change from day to day, so a re-run gets new numbers to trace.

FileWhat it isSize
README.txt What every file is, how to re-run the scores, and each file’s sha256 4.5 KB
plan.md The plan: the questions, the five-step rubric and the bar each measure had to clear 9.8 KB
results.md The scored results, the audit, the second trace and the case table 8.9 KB
experiment/answers.jsonl The 40 raw answers, never edited 56 KB
experiment/blind/answers_blind.md What the tracers saw: the answers shuffled, with the assistants’ names removed · the rubric they were given 45 KB
experiment/traces.jsonl The first trace: every page opened, the class and a reason for each number 46 KB
experiment/traces2/ The second, independent trace, in four files · part 1 · part 2 · part 3 · part 4 49 KB
experiment/audit.jsonl The author’s re-trace of 10, written before the tracers’ calls were seen · the third read 3.2 KB
experiment/factcheck.jsonl Every fact-check reply from the second AI, with its verdict · factcheck.py 84 KB
experiment/score.py Prints every measure on this page from the files above · its output 4.5 KB
experiment/collect.py How the 40 answers were collected · the 20 topics 4.7 KB