About Segments Data
To improve performance when data sets are very large, Segments might use sampled data.
About Data Sampling
If your visit or visitor count is accompanied by the symbol anywhere in Segments, it means the numbers are derived from a sample of the data in your Visitor Data Mart database.
When you don't see the symbol , it means Segments is showing exact visitor counts.
Data and Time Periods
The time period shows when the visitor activity occurred. As you explore data, the time period at the top of the interface controls the amount of data for the entire discovery tree. You can't change the time period for individual nodes.
You can choose from the following options to apply a time period to objects on the canvas.
- This includes today and can be applied to the current week, month, quarter, or year. This Day is equal to today.
- Last includes today and applies to the number of days that you specify. Last 1 Days is equal to today. Last 2 Days is equal to today and yesterday.
- Specific includes the start and end dates that you specify.
If you change the time period after adding objects to the canvas, Segments adjusts the data based on the new time period. If no data exists for that time period, objects in the tree are removed and replaced with the message "No data available for the selected period."
As you build a segment you intend to save, the time period at the top of the interface controls the amount of data used for previewing visitor counts. However, this time period is not saved with the segment definition. To include a time period with a definition, you must define it in the object itself.
When you're building a segment, you can refresh the visitor count for the segment by clicking the refresh button at the bottom of the canvas. When your visitor count is ready to be refreshed, you see this message:
Click the to refresh.
Refreshing the visitor count helps you get an idea of the size of your segment. Remember, if the visitor count is based on sampled data, it may be different when you extract data based on the segment.