1. Day 91
Learning Target:
Students can use statistics appropriate to the shape of the data distribution to compare center (median, mean) and spread (interquartile range, mean absolute deviation) of two or more different data sets.

2. Mean Absolute Deviation (MAD)
Another measure of variability is called the mean absolute deviation - the average of the absolute values of the differences between each data value in a data set and the set's mean. In other words, it is the average distance that each value is away from the mean.

3. Mean Absolute Deviation (MAD)
If a data set has a small mean absolute deviation, then this means that the data values are relatively close to the mean.
If the mean absolute deviation is large, then the values are spread out and far from the mean.

4. To find the MAD: Find the mean ( 𝐱 )
Subtract the mean from each data value (x  𝐱 )
Take the absolute value of each value from step #2. ( 𝐱− 𝐱 )
Add up all values from step #3.
Divide by the number of data values.