EAP Interpreting Academic Data 3 — Questions and Answers
Question 1: A histogram shows a distribution that is skewed to the right. What does this tell you about the data?
- Most values are high, with a few very low values
- Most values are low, with a few very high values (Correct answer)
- The data is evenly distributed
- The mean and median are equal
Correct answer: Most values are low, with a few very high values
A right-skewed distribution has most data concentrated at lower values, with a tail extending toward higher values.
Question 2: In a data table, the abbreviation 'SD' appears next to mean values. What does SD stand for?
- Significant Difference
- Standard Deviation (Correct answer)
- Sample Distribution
- Statistical Denominator
Correct answer: Standard Deviation
SD stands for Standard Deviation, a measure of how spread out the data values are around the mean.
Question 3: A researcher shows two graphs with identical data but different x-axis scales. What is the most likely effect?
- One graph will appear to show a steeper trend than the other (Correct answer)
- Both graphs will look identical
- The correlation coefficient will differ between graphs
- The sample size will appear different
Correct answer: One graph will appear to show a steeper trend than the other
Changing the axis scale alters the visual slope of trends, making the same data appear to change more steeply or gradually.
Question 4: Which of the following best describes an outlier in a dataset?
- A value that falls far outside the typical range of the data (Correct answer)
- The most frequently occurring value
- The average of the highest and lowest values
- A value that equals the mean
Correct answer: A value that falls far outside the typical range of the data
An outlier is a data point that lies an abnormal distance from other values, which can skew analysis if not properly addressed.
Question 5: A table reports data for three groups with sample sizes of n=12, n=8, and n=150. What should a careful reader consider?
- The group with n=150 should be excluded as an outlier
- Results from smaller groups may be less reliable due to limited statistical power (Correct answer)
- All groups are equally reliable regardless of sample size
- Larger samples always produce larger effect sizes
Correct answer: Results from smaller groups may be less reliable due to limited statistical power
Small sample sizes reduce statistical power and reliability, so conclusions drawn from groups with n=8 or n=12 should be interpreted cautiously.
Question 6: In a Venn diagram used in academic research, what does the overlapping region represent?
- Items unique to the first set only
- Items that belong to both sets simultaneously (Correct answer)
- The total number of items studied
- Items excluded from the study
Correct answer: Items that belong to both sets simultaneously
The overlapping area of a Venn diagram represents elements that share characteristics of both sets being compared.
Question 7: A study presents data showing that ice cream sales and drowning rates both increase in summer. What is the most accurate interpretation?
- Ice cream consumption causes drowning
- Both variables are correlated but likely share a common cause (hot weather) (Correct answer)
- The data proves that summer is dangerous
- Drowning rates cause people to buy ice cream
Correct answer: Both variables are correlated but likely share a common cause (hot weather)
This is a classic example of a spurious correlation; both variables increase in summer due to the confounding variable of hot weather, not because one causes the other.
EAP Interpreting Academic Data 3
A histogram shows a distribution that is skewed to the right.
What does this tell you about the data?