![]() ![]() Step 1: split each value in the dataset into a “stem” and a “leaf. Step 2: To make the plot, place the “stems” along the vertical axis and the “leaves” along the horizontal axis: The “stem” of each value is the first digit: Step 1: split each value in the dataset into a “stem” and a “leaf.” Here is what the stem and leaf plot looks like: The following two examples illustrate how to create a stem-and-leaf plot from scratch for a given dataset.ġ2, 14, 18, 22, 22, 23, 25, 25, 28, 45, 47, 48 This tutorial explains how to create and interpret stem-and-leaf plots. I will leave that as an exercise for the motivated reader.A stem-and-leaf plot displays data by splitting up each value in a dataset into a “stem” and a “leaf.” ![]() It would be easy to convert the code into a macro to handle different cases. The SGPLOT code is very similar as before. This results in a plot with 10 "bins", with a list of values per bin. For data with a large spread (0-999) this could result in a very tall graph to display all 100 values of Stem.įor this data I extracted only 1 digit for the Stem, and retained the remaining digits for Leaf. It is the only number with a stem of 2, so that makes it the only number in the 20’s. In the stem and leaf plot below, the first number represented is 21. One could extract two digits for the Stem, with one digit for Leaf. A stem-and-leaf plot consists of a vertical stem containing the first digit of each number, with the rest of each number written to the right of the stem like a leaf. In such a case, there are multiple ways to extract the Stem and Leaf values. Once again, the number of observations may be 0 or < 1000. ![]() For that case, I generated a data set with about 50 values ranging from 0-999. When the data values become bigger, one needs a different technique. For pre SAS9.40M3 release, you can use the SCATTER plot as shown in the linked code. This code uses the TEXT plot to display the values. Yaxis display= (noticks nolabel ) integer values= ( 4 to 9 by 1 ) reverse fitpolicy=none Xaxis display=none offsetmin= 0.05 max= 10 Text x= x y=stem text=leaf / textattrs= (size= 9 ) strip Proc sgplot data=stemleafGraph noautolegend noborder The data is shown below that includes the raw "Value" and the computed "Stem" and "Leaf" columns, followed by the plot and the SGPLOT code. If we define the first digit in each value as the stem and the second digit as the leaf. Leaf values that belong to same stem are given increasing x values for plotting. A stem-and-leaf plot is a type of plot that displays data by splitting up each value in a dataset into a stem and a leaf. For the test values below 100, Stem=Value/10 and Leaf=Value-Stem*10. The data is prepared for plotting by first sorting the data by score and then extracting the Stem and Leaf value as shown in the linked full program below. This is because while I loop from 1 to 15, I keep only the values > 0 or < 100, so the actual number of observations may be less. Keen observers may notice that I have less than 15 observations in the data. ![]() Clearly, this visual works well for moderate amount of data of 10-100 observations, and can quickly get cluttered for larger data.įor this article, I used the RANNOR() function to simulate some test score data for a class or about 15 students. One nice feature of the plot is it shows the actual values in the data. This graph was particularly useful before the advent of modern statistical graphs including the Histogram and Box Plot. A Stem and Leaf plot is a visual that can help quickly visualize the distribution of the data. ![]()
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