Finding and Comparing of Center and Spread

Given the following distributions, which has the highest median?

• Red

• Purple

• Black

Given the following distributions, which has the smallest IQR?

• Red

• Purple

• Black

Given the following distributions, which is symmetric?

• Red

• Purple

• Black

Given a set of skewed data, which is an appropriate measure of center?

• Mean

• Median

• Mode

The graph represents the participation grade for a sample of 246 students in an introductory college course.

What is the best measure of center and spread for this distribution?

• Mean and Standard Deviation

• Mean and IQR

• Median and Standard Deviation

• Median and IQR

Which summary statistic should be used to compare the two data sets and why?

• The median and the interquartile range because they are normally distributed.

• The median and the interquartile range because they are skewed.

• The mean and the standard deviation because they are normally distributed.

• The mean and the standard deviation because they are skewed.

What does the interquartile range (IQR) measure?

• The range of the entire data set

• The spread of the middle 50% of the data

• The average value of the data set

• The difference between the mean and median

Given a set of symmetric data, which of the following is an appropriate measure of spread?

• Mean

• Median

• Standard Deviation

• Interquartile Range (IQR)

Given a set of skewed data, which is an appropriate measure of spread?

• Mean

• Median

• Standard Deviation

• Interquartile Range (IQR)

We use the median and IQR for the center and spread of skewed data since they are resistant to outliers.

• True

• False