Data Analysis & Reporting Flashcards

A dataset has values: 4, 7, 7, 9, 12, 15, 21. What is the interquartile range (IQR)?

Answer: 8

Q1 = 7 and Q3 = 15, so IQR = 15 - 7 = 8, representing the spread of the middle 50% of data.

Which type of data display would best show how a single student's monthly quiz scores changed over an entire school year?

Answer: Line graph

A line graph is ideal for showing trends and changes in a variable over continuous time periods.

A teacher administers the same standardized test to 30 students and gets highly consistent results each time. This test is said to have high:

Answer: Reliability

Reliability refers to the consistency of a test in producing the same results across repeated administrations.

In a frequency table, the relative frequency column shows values that should sum to approximately:

Answer: 100 or 1.0

Relative frequencies represent proportions or percentages of the total, so they sum to 1.0 (or 100%).

A student scores at the 75th percentile on a standardized test. This means:

Answer: The student scored higher than 75% of the norm group

A percentile rank of 75 means the student performed as well as or better than 75% of the students in the comparison group.

Which of the following best describes a positively skewed distribution?

Answer: The tail extends to the right

A positively skewed distribution has a longer tail on the right side, pulling the mean above the median.

When calculating standard deviation, a larger value indicates:

Answer: Data points are more spread out from the mean

Standard deviation measures dispersion; a larger value means data points deviate more from the mean on average.