Statistics Descriptive Statistics & Data Summarization

Question 1

Which measure of central tendency is most affected by extreme outliers in a dataset?

Accepted Answer

Mean

Answer

The mean is most affected by outliers because it incorporates every value in its calculation.

Question 2

What does the interquartile range (IQR) measure?

Accepted Answer

The range of the middle 50% of data

Answer

The IQR is Q3 minus Q1, capturing the spread of the central 50% of the data.

Question 3

A dataset has values: 2, 4, 4, 6, 8. What is the median?

Accepted Answer

4

Answer

With 5 values sorted in order, the median is the 3rd value, which is 4.

Question 4

Which graphical display is best suited for showing the distribution of a single quantitative variable?

Accepted Answer

Histogram

Answer

A histogram displays the frequency distribution of a continuous quantitative variable using bins.

Question 5

What is the variance of the dataset {2, 4, 4, 4, 5, 5, 7, 9}?

Accepted Answer

4

Answer

The mean is 5 and the average squared deviation from the mean equals 4.

Statistics Practice Test