Watson-Glaser Critical Thinking Appraisal Interpreting Evidence and Data Questions and Answers 3 — Questions and Answers
Question 1: A study shows that cities with more libraries have lower crime rates. What is the most justified interpretation of this data?
- Libraries directly cause crime reduction
- There is an association between library density and crime rates, but causation is unproven (Correct answer)
- Building more libraries will always reduce crime
- Crime rates determine how many libraries a city builds
Correct answer: There is an association between library density and crime rates, but causation is unproven
The data shows a correlation, but establishing causation requires ruling out confounding variables such as overall city wealth or education spending.
Question 2: A dataset shows employee productivity rose 15% after a new policy was introduced. A colleague says the policy worked. What additional information is most critical before accepting this conclusion?
- The names of employees who improved
- Whether productivity was already trending upward before the policy (Correct answer)
- The cost of implementing the policy
- The opinion of the HR department
Correct answer: Whether productivity was already trending upward before the policy
Without knowing the pre-existing trend, it is impossible to attribute the productivity increase to the policy rather than a pre-existing trajectory.
Question 3: A table shows that 80% of surveyed customers rated a product 'excellent.' The sample size was 10 people. What is the primary limitation of this evidence?
- The rating scale is subjective
- The sample is too small to reliably generalize to all customers (Correct answer)
- Customers are biased toward positive ratings
- The survey was not conducted online
Correct answer: The sample is too small to reliably generalize to all customers
A sample of 10 is far too small to draw reliable conclusions about the broader customer population.
Question 4: Data shows that runners who stretch before exercise have more injuries than those who do not. Which interpretation is best supported?
- Stretching causes injuries in runners
- Runners with prior injuries may stretch more as a precaution, explaining the association (Correct answer)
- Stretching should be banned for runners
- The data proves stretching is useless
Correct answer: Runners with prior injuries may stretch more as a precaution, explaining the association
Reverse causation is plausible: injured or injury-prone runners may be more likely to stretch, creating a misleading association.
Question 5: A graph shows ice cream sales and drowning incidents both peak in summer. What should you conclude?
- Ice cream consumption increases drowning risk
- Both variables share a common cause — summer heat and outdoor activity — rather than a direct link (Correct answer)
- Drowning incidents cause increased ice cream sales
- The data is too limited to analyze
Correct answer: Both variables share a common cause — summer heat and outdoor activity — rather than a direct link
Both variables are driven by a third factor (summer season), making this a classic example of a confounding variable, not causation.
Question 6: A report states that 'most experts agree' that a new drug is effective, but does not cite specific studies. How should this evidence be treated in Watson-Glaser reasoning?
- Accept it as conclusive because experts are reliable
- Treat it as weak evidence until specific, verifiable data is provided (Correct answer)
- Reject it entirely because experts can be wrong
- Use it only if the drug company endorses it
Correct answer: Treat it as weak evidence until specific, verifiable data is provided
Appeal to unnamed authority without supporting data is considered weak evidence; verifiable studies are required for strong interpretation.
Question 7: A pie chart shows that Department A uses 60% of a company's budget. A manager concludes Department A is wasteful. What is wrong with this interpretation?
- Pie charts are unreliable data displays
- Budget share alone does not indicate waste without knowing the department's size, output, or responsibilities (Correct answer)
- Department A should always get less than 50%
- The conclusion is correct if the company is losing money
Correct answer: Budget share alone does not indicate waste without knowing the department's size, output, or responsibilities
Budget proportion is meaningless without context — a larger or more critical department may legitimately require more resources.
Watson-Glaser Critical Thinking Appraisal Interpreting Evidence and Data Questions and Answers 3
A study shows that cities with more libraries have lower crime rates.
What is the most justified interpretation of this data?