EAP Interpreting Academic Data 5 — Questions and Answers
Question 1: An academic article presents a funnel plot in a meta-analysis. What is the primary purpose of this type of plot?
- To show the distribution of sample sizes across studies
- To detect potential publication bias by checking for asymmetry (Correct answer)
- To rank studies from highest to lowest quality
- To compare the means of individual studies
Correct answer: To detect potential publication bias by checking for asymmetry
Funnel plots are used in meta-analyses to detect publication bias; a symmetric funnel suggests unbiased reporting, while asymmetry may indicate bias.
Question 2: A table shows data with asterisks (*) next to certain values, and a footnote reads '* p < 0.05.' What does the asterisk indicate?
- The value is an outlier
- The result for that value is statistically significant (Correct answer)
- The measurement was taken twice
- The data point is estimated, not measured
Correct answer: The result for that value is statistically significant
Asterisks in academic tables conventionally flag statistically significant results, with footnotes specifying the significance threshold used.
Question 3: When comparing two box plots, the interquartile range (IQR) of Group A is much larger than Group B's. What does this suggest?
- Group A has a higher median
- Group A's middle 50% of scores are more spread out (Correct answer)
- Group A has more participants
- Group A's data is more normally distributed
Correct answer: Group A's middle 50% of scores are more spread out
The IQR spans the middle 50% of data values, so a larger IQR indicates greater spread or variability within that central portion of the distribution.
Question 4: A researcher notes that two variables have a correlation of r = -0.89. How should this be interpreted?
- There is a weak positive relationship between the variables
- There is a strong negative relationship — as one variable increases, the other decreases (Correct answer)
- The variables are unrelated
- There is a moderate negative relationship
Correct answer: There is a strong negative relationship — as one variable increases, the other decreases
An r value of -0.89 is close to -1, indicating a strong negative (inverse) correlation between the two variables.
Question 5: In an academic figure caption, you read: 'Data are expressed as mean ± SEM, n=30 per group.' What does SEM stand for?
- Standard Error of the Mean (Correct answer)
- Significant Effect Measure
- Standardized Estimation Method
- Sample Estimation Model
Correct answer: Standard Error of the Mean
SEM stands for Standard Error of the Mean, which estimates how much the sample mean is likely to differ from the true population mean.
Question 6: A heat map uses color intensity to represent data values in a matrix. Darker colors represent higher values. A cell appears very dark. What should a reader conclude?
- That cell's data is missing or invalid
- That cell represents a relatively high value compared to other cells (Correct answer)
- The cell's variable was not measured
- The relationship in that cell is statistically significant
Correct answer: That cell represents a relatively high value compared to other cells
In a heat map where darker colors represent higher values, a very dark cell indicates a high magnitude for that particular data point or relationship.
Question 7: A study compares pre-test and post-test scores for the same group of students. Which statistical approach is most appropriate for this design?
- Independent samples t-test
- One-way ANOVA
- Paired samples t-test (Correct answer)
- Chi-square test
Correct answer: Paired samples t-test
A paired samples t-test is designed for comparing two related measurements from the same participants, such as pre- and post-test scores.
EAP Interpreting Academic Data 5
An academic article presents a funnel plot in a meta-analysis.
What is the primary purpose of this type of plot?