STAT Interpreting Informative Texts 2 — Questions and Answers
Question 1: A passage states: 'The glacier retreated 200 meters annually from 1990 to 2010, then 350 meters annually from 2010 to 2020.' What can be correctly inferred?
- The glacier has fully melted
- The rate of retreat increased after 2010 (Correct answer)
- The glacier retreated the same distance each decade
- Retreat slowed due to climate intervention
Correct answer: The rate of retreat increased after 2010
The annual retreat rate rose from 200 m to 350 m after 2010, indicating an accelerating trend.
Question 2: A graph caption reads: 'Figure 3 shows median household income by region, adjusted for inflation (2020 dollars).' What does 'adjusted for inflation' signal to the reader?
- Income values have been rounded to the nearest thousand
- Figures are comparable across years in real purchasing power (Correct answer)
- Only 2020 data is shown
- Regional differences have been removed
Correct answer: Figures are comparable across years in real purchasing power
Inflation adjustment converts all values to a common price level, allowing meaningful year-to-year comparisons.
Question 3: An informational text uses the phrase 'correlation does not imply causation' after presenting survey data. The author's purpose is most likely to:
- Dismiss the survey findings entirely
- Warn readers against assuming one variable causes another (Correct answer)
- Introduce a competing hypothesis
- Explain why the sample size is too small
Correct answer: Warn readers against assuming one variable causes another
The phrase cautions readers that a statistical relationship between variables does not prove one causes the other.
Question 4: A science article states: 'Participants who slept fewer than six hours reported higher stress levels (p < 0.05).' What does p < 0.05 indicate?
- The result occurred by chance more than 5% of the time
- The finding is statistically significant at the 5% level (Correct answer)
- Only 5% of participants reported higher stress
- The effect size is small
Correct answer: The finding is statistically significant at the 5% level
A p-value below 0.05 means there is less than a 5% probability the result is due to random chance, meeting a standard significance threshold.
Question 5: A text presents two columns: 'Observed Frequency' and 'Expected Frequency.' A reader can conclude the author is most likely discussing:
- A budget comparison
- A statistical analysis comparing actual versus predicted outcomes (Correct answer)
- A timetable for scheduled events
- A historical record of past experiments
Correct answer: A statistical analysis comparing actual versus predicted outcomes
Observed vs. expected frequency is standard terminology in statistical tests such as chi-square analysis.
Question 6: A passage includes this sentence: 'While proponents argue the policy reduces costs, critics contend it shifts costs onto consumers.' This sentence primarily serves to:
- Prove the policy is ineffective
- Present opposing perspectives on the policy's impact (Correct answer)
- Endorse the critics' view
- Provide quantitative evidence
Correct answer: Present opposing perspectives on the policy's impact
The sentence balances two conflicting interpretations, showing both sides of the debate without taking a position.
Question 7: An infographic uses a broken y-axis starting at 80% rather than 0%. A critical reader should recognize this as:
- A sign that the data is fabricated
- A technique that can exaggerate the visual difference between values (Correct answer)
- Standard practice that always improves clarity
- Evidence of a methodological error in data collection
Correct answer: A technique that can exaggerate the visual difference between values
A truncated axis amplifies apparent differences between bars or lines, potentially misleading viewers about the magnitude of change.
STAT Interpreting Informative Texts 2
A passage states: 'The glacier retreated 200 meters annually from 1990 to 2010, then 350 meters annually from 2010 to 2020.' What can be correctly inferred?