Verbal Reasoning Flashcards

A passage states hospitals in city A have better outcomes than hospitals in city B. City A hospitals are larger. The author concludes larger hospitals produce better outcomes. What weakens this?

Answer: City A is wealthier and has healthier patients on average

If city A patients are generally healthier (case-mix difference), the hospitals' size is a confounding variable rather than the cause of better outcomes.

'This painkiller reduced pain scores by 50% in trials.' A patient concludes it will halve her pain. Which caveat is most important?

Answer: Trial results are averages — her individual response may differ

Average trial results do not predict individual outcomes. The patient's pain may reduce by more, less, or not at all depending on her specific condition.

Passage: 'Speed cameras reduced accidents at monitored junctions by 30%.' The transport minister announces cameras will be installed everywhere. Which assumption does this require?

Answer: Cameras will be equally effective at all junctions, not just those already chosen for cameras

Sites chosen for cameras are often already high-accident locations (regression to the mean risk). Assuming the same reduction everywhere requires the assumption that location type does not matter.

A writer argues: 'Since ancient Greeks practised democracy, democracy is the oldest and most natural form of government.' Identify the flaw.

Answer: Age does not establish that something is natural or best — the argument conflates origin with value

Arguing from antiquity (appeal to tradition) — the fact that something is old does not make it natural or superior. This is a classic logical fallacy.

'Every student who failed the test admitted they had not revised. Therefore, revision guarantees passing.' What is wrong?

Answer: The evidence only shows that non-revision is associated with failure, not that revision guarantees success

Knowing non-revision is linked to failure does not establish that revision is sufficient for passing. Other factors may prevent success despite revising.

Passage mentions a correlation of r=0.85 between exercise and life expectancy. What does this most accurately indicate?

Answer: A strong positive association between exercise and life expectancy

A correlation coefficient of 0.85 indicates a strong positive association. Correlation alone does not establish causation, and the statistic does not represent a percentage of people or a percentage increase.