We then order the leaves, as in Table 4. Simple inspection can disclose irregularities. Furthermore, a glance at the figures gives information on their range . For 15 points, the mid point is clearly the eighth largest, so that seven points are less than the median, and seven points are greater than it. To find the median for an even number of points, the procedure is as follows.
Data display The simplest way to show data is a dot plot .
Figure 1 shows the data from Tables 2 and 5 and together with the median for each set. When the data sets are large, plotting individual points can be cumbersome. An alternative is a box-whisker plot . The box is marked by the first and third quartile, and the whiskers extend to the range. The median is also marked in the box, as shown in Figure 2.