Watson-Glaser Critical Thinking Appraisal Watson-Glaser Critical Thinking Appraisal Assessing Probability of Inferences Questions and Answers 4 — Questions and Answers
Question 1: Passage: A company replaced fluorescent lighting with LED lighting throughout its offices. Employee complaints about headaches fell by 40% in the next quarter. Inference: 'LED lighting caused the reduction in employee headaches.' How should this inference be rated?
- True
- Probably True
- Insufficient Data (Correct answer)
- Probably False
Correct answer: Insufficient Data
There is insufficient data because no control group was used and other changes during the same quarter (stress levels, ventilation, staffing) may explain the reduction.
Question 2: Passage: In the past decade, nations with higher per-capita chocolate consumption have higher Nobel Prize winner rates per capita. Inference: 'Eating chocolate improves cognitive ability and increases the chance of winning a Nobel Prize.' How should this inference be rated?
- Probably True
- Insufficient Data
- Probably False
- False (Correct answer)
Correct answer: False
The inference is probably false because both chocolate consumption and Nobel laureates likely correlate with national wealth—a classic spurious correlation.
Question 3: Passage: A teacher states: 'None of my students who completed all homework assignments failed the final exam.' Inference: 'Students who complete all homework assignments will pass the final exam.' How should this inference be rated?
- True
- Probably True (Correct answer)
- Insufficient Data
- Probably False
Correct answer: Probably True
The inference is probably true because the teacher's data shows a consistent pattern, though future students could still fail despite completing homework.
Question 4: Passage: Sales of umbrellas in a coastal city spike every June and July. Inference: 'It rains more in June and July in this coastal city than in other months.' How should this inference be rated?
- True
- Probably True
- Insufficient Data (Correct answer)
- Probably False
Correct answer: Insufficient Data
There is insufficient data because coastal cities may have high June-July tourism, causing umbrella purchases for sun protection rather than rain.
Question 5: Passage: 'Every student in Mr. Kim's advanced math class scored above 90% on the state standardized test.' Inference: 'Mr. Kim is an excellent math teacher.' How should this inference be rated?
- True
- Probably True
- Insufficient Data (Correct answer)
- Probably False
Correct answer: Insufficient Data
There is insufficient data because the class is labeled 'advanced,' suggesting students were pre-selected for high ability, making teacher quality impossible to isolate.
Question 6: Passage: A pharmaceutical trial showed Drug X reduced blood pressure in 85% of participants, while a placebo reduced it in 20%. The trial was double-blind with 1,000 participants. Inference: 'Drug X is effective at reducing blood pressure.' How should this inference be rated?
- True (Correct answer)
- Probably True
- Insufficient Data
- Probably False
Correct answer: True
'True' is appropriate here because a double-blind RCT with 1,000 participants showing a 65-percentage-point difference over placebo is conclusive evidence, making this a valid deduction from the data.
Question 7: Passage: Residents of Maplewood report that since a new highway opened nearby, traffic on Main Street has decreased. Inference: 'The new highway has diverted traffic away from Main Street.' How should this inference be rated?
- True
- Probably True (Correct answer)
- Insufficient Data
- Probably False
Correct answer: Probably True
The inference is probably true because a new parallel highway diverting traffic is the most logical explanation for a reduction in traffic on Main Street.
Watson-Glaser Critical Thinking Appraisal Watson-Glaser Critical Thinking Appraisal Assessing Probability of Inferences Questions and Answers 4
Passage: A company replaced fluorescent lighting with LED lighting throughout its offices.
Employee complaints about headaches fell by 40% in the next quarter.
Inference: 'LED lighting caused the reduction in employee headaches.' How should this inference be rated?