What is an ogive?How to construct it? PLz give one or 2 examples.
An Ogive is a graph of a cumulative distribution, which shows data values on the horizontal axis and either the cumulative frequencies, the cumulative relative frequencies or cumulative percent frequencies on the vertical axis. The Ogive is constructed by plotting a point corresponding to the cumulative frequency of each class.
For example:
| Class | 10-20 | 20-30 | 30-40 | 40-50 | 50-60 | 60-70 | 70-80 | 80-90 |
| F | 3 | 15 | 8 | 20 | 7 | 4 | 6 | 2 |
First lets find the more than cumulative frequency corresponding to each class. For this the frequencies of the succeeding classes are added to the frequency of a class.
| Lower limit | Frequency More than | Cumulative Frequency |
| 10 | 3 | 65 |
| 20 | 15 | 65 - 3 = 62 |
| 30 | 8 | 62 - 15 = 47 |
| 40 | 20 | 47 - 8 = 41 |
| 50 | 7 | 41 - 20 = 19 |
| 60 | 4 | 19 - 7 = 12 |
| 70 | 6 | 12 - 4 = 8 |
| 80 | 2 | 8 - 6 = 2 |
Now we draw the horizontal and vertical axes and label them. Plot the cumulative frequencies corresponding to the lower limit of each class and join the points using a smooth curve.