Numerical Summaries of Data

Front

What is the mean absolute deviation (MAD)?

Back

The mean absolute deviation (MAD) is a measure of the dispersion of a set of data points. It is calculated by taking the average of the absolute differences between each data point and the mean of the data set.

Front

What is the median in a data set?

Back

The median is the middle value of a data set when it is ordered from least to greatest. If there is an even number of observations, the median is the average of the two middle numbers.

Front

What does it mean if a data set is skewed right?

Back

A data set is skewed right when the tail on the right side of the distribution is longer or fatter than the left side. This often indicates that the mean is greater than the median.

Front

What is the interquartile range (IQR)?

Back

The interquartile range (IQR) is a measure of statistical dispersion, calculated as the difference between the third quartile (Q3) and the first quartile (Q1). It represents the range of the middle 50% of the data.

Front

How do you find the mode of a data set?

Back

The mode is the value that appears most frequently in a data set. A data set may have one mode, more than one mode, or no mode at all.

Front

What is the relationship between mean, median, and mode in a skewed distribution?

Back

In a skewed distribution, the mean is pulled in the direction of the skew. For a right-skewed distribution, the mean is greater than the median, which is greater than the mode.

Front

What is a data set?

Back

A data set is a collection of related data points or values that can be analyzed to extract meaningful information.

Front

What is the range of a data set?

Back

The range is the difference between the highest and lowest values in a data set. It provides a measure of how spread out the values are.

Front

What is a quartile?

Back

A quartile is a type of quantile that divides a data set into four equal parts. The first quartile (Q1) is the median of the lower half, the second quartile (Q2) is the median, and the third quartile (Q3) is the median of the upper half.

Front

What is the purpose of using the median as a measure of center?

Back

The median is used as a measure of center because it is not affected by extreme values (outliers) and provides a better representation of the center of a skewed distribution.