What is the relationship between the second quartile (Q2) and the median in a data set?

The second quartile (Q2) is synonymous with the median in a data set, as it represents the value below which 50% of the observations fall.

True or False: Quartile deviation is affected by extreme values in a data set.

False. Quartile deviation is not affected by extreme values, as it only considers the middle 50% of observations.

What does a high coefficient of variation indicate about a data set?

High CV indicates high variability.

• Relative variability measure.

• Standard deviation is large.

• Mean significantly affects data.

Explain how the variance and standard deviation are related mathematically.

Variance is the square of the standard deviation, mathematically expressed as Variance = σ², where σ is the standard deviation.

Fill in the blank: The formula for the coefficient of variation is ___ divided by the mean, expressed as a percentage.

Standard deviation

True or False: The range is a more reliable measure of dispersion than the quartile deviation.

False

Range is less reliable than quartile deviation.

• Range is influenced by extremes.

• Quartile deviation is robust measure.

• Quartiles reduce the impact of outliers.

Identify the two types of measures of dispersion and give an example of each.

The two types of measures of dispersion are absolute measures (e.g., range) and relative measures (e.g., coefficient of variation).

How do you interpret a coefficient of variation of 25%?

A coefficient of variation of 25% indicates moderate variability.

• Standard deviation is 25% of mean.

• Indicates relative variability in data.

• Useful in comparing data sets.