2.7: Ogive 图表
An ogive graph is sometimes called a cumulative frequency polygon. It is one type of frequency polygon that shows cumulative frequency. In other words, the cumulative percentages are added to the graph from left to right. An ogive graph plots cumulative frequency on the vertical y-axis and class boundaries along the horizontal x-axis. It’s very similar to a histogram; only instead of rectangles, an ogive displays a single point where the top right of the rectangle would be. Creating this type of graph from a frequency table is usually easier. It is generally used to find the median of a given data set. Apart from finding the medians, ogive graphs are used to compute the percentiles of the data set values.
