A cumulative frequency distribution would provide（）.

為什么在計算平均指標的基礎上還有必要進一步計算變異指標？

時間序列構成因素有哪些？分解的基本原理和思路是什么？

什么是季節(jié)變動？研究它的意義何在？如何測定季節(jié)變動？

A student achieves an 82 on the first test in a statistics course. From this, she assumes that her average at the end of the semester (after other tests) will be about 82. This is an example of （）.

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). Personnel records of 50 employees are selected for analysis. (The plant employs 250.) For this study, the average number days absent for these 50 employees is a （）.

品合格率指標是（）

常用的長期趨勢測定的方法有哪些？各有什么特點？

要了解某地區(qū)全部大學生的就業(yè)情況，那么（）

If the individual class frequency is divided by the total frequency, the result is the （）.