简单次数分布表（Simple Frequency Table）
将相同值的数据归为一组后，可以得到每个值出现的次数，将这些次数以表的形式表示出来，将数据（X）从小到大排成一列，再在另一列列出每个数值出现的次数（f），这样就得到了最简单的次数分布表。
After grouping the data of the same value, the number of times which each value occurs can be obtained. These times are expressed in the form of a table, by arranging the data (X) in a column by increasing sequence, and then listing the number of times each value occurs(f) in another column , which gives the simplest frequency distribution table.
简单次数分布表中f列的每格列出的是数值出现的次数，要计算出所有数据的个数，我们只需要将f列的所有数据相加，即：
Each cell of column f in the simple frequency table lists the number of times the value occurs. In order to calculate the number of all the data, we just need to add up all the data in column f, i.e.:
有时候我们需要计算变量总和，这时候只要将所有的分数相加，即：
Sometimes we need to calculate the sum of variables. At this point we could add up all the fractions, i.e:
比例（proportions）就是全组中取值为X的比例，计算公式为:
Proportions are the proportions of the whole group with value X. The formula is as follows.
百分比（percentages）就是将小数形式的比例乘以100转换而成的。
Percentages are the conversions of proportions in decimal form multiplied by 100.
分组次数分布表（Grouped Frequency Table）
当样本可取的数据的数值比较多时，我们就需要对数值进行分组。进行分组数据统计，关键的一点就是划分数据区间，也就是确定每组的取值范围。每组中包含的数据值的最大值与最小值的差距我们称为组距，一般来说，81-90的数据组，我们认为80.5为数据值的最小值，而90.5为数据的最大值。全部数据的最大值与最小值的差距叫做全距。而当组数确定之后，我们可以大概确定组距，三者的关系为：
When the accessible data is abundant, it is necessary to divide them into groups. The key point to grouped data analysis is to divide the data intervals, that is to ascertain the value range of each groups. The division of the maximum and minimum is called group range. Usually, for a group from 81 to 90, the minimum is regarded as 80.5, while the maximum is regarded as 90.5. The division of the maximum and minimum of all the data is called range. And once the group amount is ascertained, the group range could be roughly estimated, the relationship of the three statistics are as follows:
(Group Range = Range/Group Amount)
当然，组距一般取较为简单的数字，如10或者5的倍数，而且每组的起点也应该尽量简单。
Meanwhile, the group range is usually set as simple numbers like the multiples of 5 or 10, and the starting point of each group should also be as simple as possible.