以2000年a0為最初水平，2016年an為最末水平，計算鋼產(chǎn)量的年平均發(fā)展速度時，須開（）

為什么在計算平均指標的基礎(chǔ)上還有必要進一步計算變異指標？

最能反映離散程度的指標是（）

A cumulative frequency polygon is also called （）.

時間序列構(gòu)成因素有哪些？分解的基本原理和思路是什么？

一個地區(qū)一定時期的商品零售額屬于（）

Which of the following is not the goal of descriptive statistics?（）

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 （）.

The number of phone calls arriving at a switchboard each hour has been recorded and the following frequency distribution has been developed.What is the approximate range of the number of phone calls arriving each hour？（）

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