![]() In a stem plot you have a vertical line dividing the stems from the leaves. Now that we know what stem plots are and how they are useful, how do we actually construct a stem plot? What do we do with a stem plot, or how do we interpret it? Steps to Interpreting a Stem Plotįirst you should know how to construct a stem plot. It would be quite cumbersome to plot out by hand hundreds of values. However, as you can probably guess, a main disadvantage of the stem plot is that it is really only useful with relatively small data sets. The primary advantage of a stem plot is that rather than condensing our data into points or into bars on a graph, we can see the original numerical values of the data. Other ways to summarize univariate data include a histogram and pie chart. The stem plot is one method of summarizing univariate data visually. Most importantly, the stem plot is useful because it can help with finding the median, mode, and quartiles of data, the range, minimum and maximum values, as well as the most and least frequently occurring observed values in the data. Because in AP® Statistics we are interested in normally distributed data, or a bell curve distribution, the stem plot is an easy and fast way to get a general feel of the distribution especially if the data has relatively few observations. The stem-and-leaf plot or stem plot, for short, is a way to quickly create a graphical display of quantitative data to get an idea of its shape. There are many different ways to get to know data, and you are probably most familiar with calculating central tendencies and measures of dispersion.Īnother thing we are interested in when describing data is its shape, which can be important for determining whether a variable is appropriate for a particular analysis later on. This is done so that you can get to know your data, find errors in data collection and data entry, and to find out basic information such as the central tendencies and dispersion characteristics of data. Create a side-by-side stem-and-leaf plot of these wins and losses.In statistics, descriptive data analysis must always be done first before anything else. The table shows the number of wins and losses the Atlanta Hawks have had in 42 seasons. Construct a side-by-side stem-and-leaf plot using this data. The two following tables show the ages of presidents at their inauguration and at their death. The leaves are to the left and the right of the stems. In a side-by-side stem-and-leaf plot, two sets of leaves share the same stem. Eight out of the 31 scores or approximately 26% were in the 90s or 100, a fairly high number of As.Ī side-by-side stem-and-leaf plot allows a comparison of the two data sets in two columns. The stemplot shows that most scores fell in the 60s, 70s, 80s, and 90s. ![]() Then write the leaves in increasing order next to their corresponding stem.įor Susan Dean's spring pre-calculus class, scores for the first exam were as follows (smallest to largest):ģ3 42 49 49 53 55 55 61 63 67 68 68 69 69 72 73 74 78 80 83 88 88 88 90 92 94 94 94 94 96 100Stem-and-Leaf Graph Draw a vertical line to the right of the stems. ![]() Write the stems in a vertical line from smallest to largest. ![]() The decimal 9.3 has stem nine and leaf three. Likewise, the number 5,432 has stem 543 and leaf two. For example, 23 has stem two and leaf three. ![]() The leaf consists of a final significant digit. To create the plot, divide each observation of data into a stem and a leaf. It is a good choice when the data sets are small. One simple graph, the stem-and-leaf graph or stemplot, comes from the field of exploratory data analysis. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |