Unit 5 · Weakening Arguments
Local Council Report — Weaken the Argument
Lesson 2 of 2
Now for a more subtle and demanding type of weakening question — one that exposes a hidden statistical flaw rather than simply offering an alternative cause. These questions test whether you think critically about numbers, not just accept them at face value.
Statistical fallacy questions appear regularly in the harder half of OC TS Evaluating Arguments items. The "base rate" trap is one of the most frequently tested logical errors in the entire exam series.
The examiner is testing whether you can spot the missing denominator — the "base rate" — that makes a raw count statistic meaningless without context. More accidents in one place does not automatically mean higher individual risk; it may simply mean more people go there.
An authority compares the number of events (accidents, crimes, illnesses) at two different locations and concludes that one location is more dangerous. The correct weakener reveals that far more people use the supposedly "dangerous" location — so the risk per person is actually lower there.
Best approach: Whenever an argument says "more X happens at Place A, therefore Place A is riskier", immediately ask: "Do more people go to Place A?" The answer that reveals a much larger user base transforms the raw count into a rate — and that rate may tell a completely different story.
Question
A local council report found that significantly more bicycle accidents happen on the 'Blue Coastal Path' than on the 'Mountain Forest Trail.' Based on this data, the Head of Safety argued: "The Blue Coastal Path is a much more dangerous track for individual cyclists, and anyone riding there is at a higher risk of having an accident than if they rode the Mountain Forest Trail."
Which one of these statements, if true, most weakens the Head of Safety's argument?
Select an answer to see the explanation.
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