Statistics 简明教程

Statistics - Stem and Leaf Plot

茎叶图与直方图类似，但不同之处在于直方图中使用条形图比较数据，而茎叶图中的叶子代表要比较的实际数字。茎叶图也称为茎叶图，因为它有一个步骤，在左边放置最大的位值数字，在右边放置叶片。茎叶图用于绘制数量不超过 50 的定量数据。

Stemplots are similar to histogram with the difference that in histogram, bars are used to compare data and in case of stemplots leaves represents actual numbers to be compared. Stemplots are also called stem and leaves plot as there is one step with largest place value digits on the left and at leaf(ves) to the right. A Stemplot is used to draw quantitative data with fewer than 50 observations.

在茎叶图中，左侧的条目称为茎；右侧的条目称为叶。在上图中，茎是十位（此处 5 代表 50，6 代表 60，依此类推）；叶子是实际值。茎和叶可以标为百万、千、个位、十分之一等。

In a stemplot, left side entries are called stems; and the right side entries are called leaves. In figure above, the stems are tens (here 5 represents 50, 6 represents 60, and so on); and the leaves are actual values. Stems and leaves may be labelled as - millions, thousands, ones, tenths, etc.

Example

Problem Statement:

绘制以下数据点的茎叶图。

Draw Stemplot diagram for the following data points.

Solution:

Step 1 - 按升序排列数字。

Step 1 - Sort the numbers in ascending order.

Step 2 - 选择步骤为最大的位值。在我们的案例中，它是 10。因此，每个步骤将表示 10 个单位。

Step 2 - Choose step as largest place value. In our case it is 10. So each step will represent 10 units.

Step 3 - 根据茎值对数字进行分组。

Step 3 - Group the numbers based on stem value.

50
64
75	78
80	80
80	81
81	81
82	82
82	83
84	84
85	86
86	87
88	88
96	97
98	99

Step 4 - 将茎数字绘制为 10 位值数字 5、6、7、8 和 9（每个数字表示 10 个单位）。将叶子绘制为 1 位值。

Step 4 - Draw the stem numbers as 10’s place-value digits 5, 6, 7, 8 and 9 (each number is representing 10 units). Draw the leaves as 1’s place value.