Statistics Descriptive Statistics & Data Summarization 2

Question 1

Which statistic is most appropriate for describing the center of a heavily skewed income distribution?

Accepted Answer

Median

Answer

The median is resistant to skewness and extreme values, making it ideal for skewed distributions.

Question 2

What does a box plot's whisker typically represent?

Accepted Answer

1.5 × IQR beyond the quartiles

Answer

By convention, box plot whiskers extend to 1.5 times the IQR beyond Q1 and Q3.

Question 3

What is the coefficient of variation (CV) used for?

Accepted Answer

Comparing variability between datasets with different units or means

Answer

The CV expresses standard deviation as a percentage of the mean, enabling comparison across different scales.

Question 4

In a symmetric bell-shaped distribution, which of the following is true?

Accepted Answer

Mean = Median = Mode

Answer

In a perfectly symmetric unimodal distribution, all three measures of center are equal.

Question 5

Which of the following best describes a stem-and-leaf plot?

Accepted Answer

A display that preserves original data values while showing distribution shape

Answer

A stem-and-leaf plot retains actual data values while simultaneously showing the shape of the distribution.

Statistics Practice Test