One advantage of a stem and leaf plot over a frequency distribution is that （）.

Simon Arnett, Director of Human Resources, is exploring the causes of employee absenteeism at Buderim Bottling during the last operating year (1 January 2005 to 31 December 2005). The average number of absences per employee, calculated from the personnel data of all employees, is a （）.

Descriptive statistics deals with methods of（）

The number of class intervals in a frequency distribution is usually between （）.

變量數(shù)列中，各組頻率之和應(yīng)（）

If data are grouped into intervals and the number of items in each group is listed, this could be called a （）

某企業(yè)的生產(chǎn)計劃完成百分比采用如下分組，請指出哪項是正確的（）

A summary measure that is computed from a sample to describe a characteristic of the population is called（）

One rule that must always be followed in constructing frequency distributions is that （）.

常用的長期趨勢測定的方法有哪些？各有什么特點？