What is a back to back stem plot?
A back-to-back stem-and-leaf plot is a method for comparing two data distributions by attaching two sets of ‘leaves’ to the same ‘stem’ in a stem-and-leaf plot. For example, the stem-and-leaf plot below displays the distribution of pulse rates of 19 students before and after gentle exercise.
How do you make a Stemplot When is a back to back Stemplot useful?
You would use a back to back stemplot when you are comparing quantitative (numerical) data to two sets of categorical variables. For example, you might be comparing weights of pregnant women (numerical data) in the second and third trimesters (second and third trimesters are the categorical portions of the plot).
How do you read a Stemplot?
Explanation: This stemplot is read as follows: the stem is the tens digit and each digit in the “leaves” section is a ones digit. Put them together to have a data point. In the particular case there are 15 data points therefore the median is 79.
Why are back to back stem and leaf plots good?
Exploring Data A back to back stem-and-leaf plot goes one step further and allows for easy comparison of two sets of numbers.
What is the purpose of a back-to-back stemplot?
A back-to-back stemplot is used for numerical data, where two sets of data use the same set of stems, but one data set radiates to the left and the other radiates to the right. By displaying two sets of data in one stemplot, we are able to easily make comparisons of two groups.
When might a Stemplot be useful?
Stemplots show a little more information than a histogram and have been a common tool for displaying data sets since the 1970s. They are typically used when there is a medium amount of quantitative variables to analyze; Stemplots of more than 50 observations are unusual.
When should you split the stems on a Stemplot?
Splitting the stems. The organization of this stem and leaf plot does not give much information about the data. With only one stem, the leaves are overcrowded. If the leaves become too crowded, then it might be useful to split each stem into two or more components.
How do you use a stemplot?
- Step 1: Pick your “stems” and “leaves” Each of the numbers in your data set can be viewed as being made up of two parts: a stem and a leaf.
- Step 2: Draw a vertical bar with all of the stems on the left. This step sounds much more complicated than it actually is.
- Step 3: Put each leaf next to its stem, in order.
What does a back to back stem plot show?
A stem and leaf plot shows the spread and distribution of a data set. A back-to-back stem and leaf plot shows two data sets. The data sets share the same stem and have their own set of leaves. Example of a double stem and leaf plot created by QI Macros add-in for Excel. It’s easy to create both single and double stem and leaf plots using QI Macros.
How to make a back to back stemplot in Excel?
A back to back stem-and-leaf plot goes one step further and allows for easy comparison of two sets of numbers. Additionally, how do you do a back to back stem and leaf plot in Excel? Click on the QI Macros menu, then Chart Templates, then Stem and Leaf Plot to open the template. Input or cut and paste your data into the yellow input areas.
Why do you use back to back plots?
Back to back stem-and-leaf plots allow for easy comparison of two sets of like data. By breaking your data into ‘stems’ and ‘leaves,’ you can easily find the mode (i.e. the most frequently occurring number in a data set) and median (i.e. the middle number of a data set), as well as other information regarding the distribution of numbers.
What does a stem and leaf plot show?
A stem and leaf plot shows the spread and distribution of a data set. A back-to-back stem and leaf plot shows two data sets. The data sets share the same stem and have their own set of leaves.
