CAASPP Data Analysis 5 — Questions and Answers
Question 1: A back-to-back stem-and-leaf plot compares scores for two classes. Class A has more leaves on the higher stems than Class B. What can you conclude?
- Class A scored lower overall
- Class A scored higher overall (Correct answer)
- Both classes had the same median
- Class B had more students
Correct answer: Class A scored higher overall
More leaves on higher stems means more high scores, so Class A generally scored higher.
Question 2: Data set A: 10, 10, 10, 10, 10. Data set B: 2, 7, 10, 13, 18. Both have a mean of 10. How do their standard deviations compare?
- Set A has a larger standard deviation
- Set B has a larger standard deviation (Correct answer)
- They have equal standard deviations
- Standard deviation cannot be calculated for Set A
Correct answer: Set B has a larger standard deviation
Set A has zero variation (all values equal the mean), while Set B's values vary, giving it a larger standard deviation.
Question 3: A survey finds that students who sleep more hours tend to score higher on tests. This is an example of what type of relationship?
- A negative correlation
- No correlation
- A positive correlation (Correct answer)
- A causal relationship only
Correct answer: A positive correlation
When both variables increase together (more sleep → higher scores), the relationship is a positive correlation.
Question 4: In a data set with values 3, 5, 5, 7, 9, 11, what is the mean absolute deviation (MAD) if the mean is 6.67?
- 2
- 2.22 (Correct answer)
- 4
- 1.5
Correct answer: 2.22
The absolute deviations are 3.67, 1.67, 1.67, 0.33, 2.33, 4.33; their average ≈ 2.22.
Question 5: A teacher displays quiz grades on a dot plot. The plot is skewed right. What does this tell you about most students' grades?
- Most grades are high, with a few very low outliers
- Most grades are low to moderate, with a few very high outliers (Correct answer)
- The grades are evenly distributed
- There is no mode in the data
Correct answer: Most grades are low to moderate, with a few very high outliers
A right skew means the tail extends toward higher values, so most data is clustered at the lower end with a few high outliers.
Question 6: Which of the following is an example of categorical data?
- Heights of students in centimeters
- Number of books read per month
- Favorite colors of students (Correct answer)
- Daily temperatures in Fahrenheit
Correct answer: Favorite colors of students
Categorical data describes qualities or groups (like colors), not numerical measurements.
Question 7: A student claims that because ice cream sales and drowning rates both rise in summer, eating ice cream causes drowning. What error is the student making?
- Confusing mean and median
- Confusing correlation with causation (Correct answer)
- Misreading a histogram
- Ignoring the mode of the data
Correct answer: Confusing correlation with causation
Correlation between two variables does not prove that one causes the other; both may be driven by a third factor (hot weather).
CAASPP Data Analysis 5
A back-to-back stem-and-leaf plot compares scores for two classes.
Class A has more leaves on the higher stems than Class B.
What can you conclude?