EAP Interpreting Academic Data 2 — Questions and Answers
Question 1: A scatter plot shows data points clustered tightly around a line going from bottom-left to top-right. What does this indicate?
- A strong negative correlation
- A strong positive correlation (Correct answer)
- No correlation
- A curvilinear relationship
Correct answer: A strong positive correlation
Points clustered tightly around an upward-sloping line indicate a strong positive correlation between the two variables.
Question 2: In a research table, a p-value of 0.03 is reported alongside a result. What does this mean at the α = 0.05 significance level?
- The result is not statistically significant
- The result is statistically significant (Correct answer)
- The effect size is large
- The sample size is adequate
Correct answer: The result is statistically significant
A p-value of 0.03 is less than α = 0.05, so the result is statistically significant and the null hypothesis is rejected.
Question 3: A pie chart shows that one sector represents 45% of a dataset. A researcher claims this sector represents the majority. Is this claim accurate?
- Yes, because 45% is close to half
- No, because a majority requires more than 50% (Correct answer)
- Yes, because it is the largest sector
- No, because pie charts cannot show majorities
Correct answer: No, because a majority requires more than 50%
A majority requires more than 50%, so 45% does not constitute a majority even if it is the largest single segment.
Question 4: A bar graph displays error bars on each column. What do these error bars typically represent?
- The range of the raw data
- Variability or uncertainty in the data, such as standard deviation (Correct answer)
- The sample size for each group
- The statistical significance of differences
Correct answer: Variability or uncertainty in the data, such as standard deviation
Error bars represent variability or uncertainty in measurements, commonly showing standard deviation, standard error, or confidence intervals.
Question 5: When reading an academic graph, the y-axis does not start at zero. What concern does this raise?
- The data cannot be compared across groups
- Differences between values may appear exaggerated (Correct answer)
- The graph is automatically invalid
- The x-axis scale must also be adjusted
Correct answer: Differences between values may appear exaggerated
A truncated y-axis can make small differences appear much larger than they are, potentially misleading readers.
Question 6: A line graph shows two variables over time, and the lines cross at one point. What does the crossing point indicate?
- Both variables have reached their maximum values
- The two variables have equal values at that point in time (Correct answer)
- The data collection ended at that point
- One variable caused the other to change
Correct answer: The two variables have equal values at that point in time
The intersection point means both variables share the same value at that specific time, though it does not imply causation.
Question 7: A study reports a confidence interval of [2.1, 8.4] for a mean difference. What can be concluded?
- The true mean difference is exactly 5.25
- We are confident the true mean difference falls within this range (Correct answer)
- The result is not statistically significant
- The sample size was too small
Correct answer: We are confident the true mean difference falls within this range
A confidence interval gives a range within which the true population parameter is estimated to fall with a specified level of confidence.
EAP Interpreting Academic Data 2
A scatter plot shows data points clustered tightly around a line going from bottom-left to top-right.
What does this indicate?