**Cross Sectioned Data** consists of observations we derive from the analysis of demand across all service parts.

# Example

The Prior Distribution of service part demand levels relies on observing the cross section of `demand levels`

for the service parts.

If we take the mean annual demand level per part and put that demand in a histogram bucket and we do this across all parts we get the Prior Distribution of the service parts in the form of a histogram.

When we look at the parts that have a demand level of 2 per year, we may find that 5 parts out of 200 have a demand level of 2 units per year. We are looking at a segment of the cross section of our data.