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:
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:
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 |
Following is the required frequency plot
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 |
Following is the required frequency plot