The purpose of the notes is to supplement the theoretical content of most statistics texts with practical advice ... it is necessary to adjust standard errors when working with grouped data.

The median is therefore within the class interval 5-9. The mode is the most common value. In a frequency table with grouped data the best we can do is find the group with the highest frequency.

When we talk about statistical mean ... of ungrouped data is slightly different than finding the mean value of grouped data. Grouped data is when a dataset is divided into class intervals.

Working Papers describe research in progress by the author(s) and are published to elicit comments and to further debate We analyze the performance of kernel density methods applied to grouped data to ...