When a report is based on data from a large number of sessions, you may see the following notice at the top of the report: “This report is based on N sessions.” You can adjust the sampling rate of the report by:
- changing the sampling rate in your view settings
- adjusting the session timeout control
- adjusting a control in the reporting interface for greater or less precision
- You cannot adjust the sample data
When a report is based on data from a large number of sessions, you may see the following notice at the top of the report: “This report is based on N sessions.” You can adjust the sampling rate of the report by
Explanation:
Sampling in Google Analytics (or in any analytics software) refers to the practice of selecting a subset of data from your traffic and reporting on the trends detected in that sample set. Sampling is widely used in statistical analysis because analyzing a subset of data gives similar results to an analysis of a complete data set, while returning these results to you more quickly due to reduced processing time.
In Analytics, sampling can occur in your reports, during your data collection, or in both places.
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