Statistics 简明教程

Statistics - Cumulative plots

累积图是绘制累积信息的一种图表方式。它显示数量/百分比，或小于或等于特定值的对照的比例。

A cumulative plot is a way to draw cumulative information graphically. It displays the number / percentages, or proportion of observations that are less than or equal to particular value.

Example

Problem Statement:

根据以下数据绘制 10 个学生考试成绩的频率和累积频率图。

Draw the frequency and comulative frequency plots of 10 student test scores based on following data.

Sr. No.	Roll No.	Test Score
1	100	30
2	101	40
3	102	35
4	103	50
5	104	60
6	105	65
7	105	35
8	105	55
9	105	65
10	105	70

Solution:

对于频率图表，按如下所示计算频率。此表格显示的是在指定范围内得到分数的学生数量。

For the frequency chart, compute the frequecies as shown below. This table show the no. of students scoring in given ranges.

Sr. No.	Frequency	Students
1	30-40	3
2	40-50	1
3	50-60	2
4	60-70	3
4	70-80	1

以下是所需的频率图：

Following is the required frequency plot

对于累积频率图表，按如下所示计算频率。此表格显示的是得到指定分数及以下分数的学生数量（包括）。

For the comulative frequency chart, compute the frequecies as shown below. This table show the no. of students scoring upto given marks(including).

Sr. No.	Upto Score	Students
1	30	1
2	40	3
3	50	4
4	60	7
5	70	10

以下是所需的频率图：

Following is the required frequency plot