變量數(shù)列中，各組頻率之和應(yīng)（）

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 （）.

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

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 （）.

時(shí)間序列構(gòu)成因素有哪些？分解的基本原理和思路是什么？

Which of the following statements is not true？（）

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

對某班級(jí)學(xué)生的生活狀況進(jìn)行統(tǒng)計(jì)調(diào)查，下列標(biāo)志中屬于不變標(biāo)志的是（）

Which of the following is best to show the percentage of a total budget that is spent on each category of items？（）

某廠某年職工勞動(dòng)生產(chǎn)率為20000元，是歷史最高水平的1.2倍。這里的1.2倍是（）