Once the data are obtained, it might be nice to summarize the data. Data values 64, 69 and 73 are recorded as shown below: Key Terms stemplot , stem-and-leaf plot , stem , leaf , outlier. For example, the first number in the depths column is a 1. Let’s take the efficient route, as most anyone would likely taken in practice, by letting Minitab generate the plot for us:. Our IQ data set produces stems 6, 7, 8, 9, 10, 11, 12, 13, and Here’s what Minitab’s stem-and-leaf plot of the 64 IQs looks like:. Then we construct an ordered stemplot from the unordered version by arranging the leaves in ascending order.

To create the plot then, we first create a column of numbers containing the ordered stems. Distributions of Functions of Random Variables. The stemplot for the data consisting of outliers can be displayed as follows: An ordered stemplot is obtained by arranging the leaves in order, as shown below. For the leaf part of the plot. Then, ignoring the first column of numbers for now, the second column contains the stems from 6 to

In a stemplot i.

If the stem and leaf plot were about the altitudes of the Rocky Mountains, it would look the same. Why is there no oddered for punctuation to separate the data points? For each value of the data, the stem is the tens digit and the leaf is the units digit. The third number in the depths column is a 3. Year 9 Interactive Maths – Second Edition.

## Stem-and-Leaf Plots

But the key would look like this: Note that 3 48 represents the data value The number of cubes they collected is shown below. Instead, you’d probably want to let some statistical software, such as Minitab or SAS, do the work for you.

In this section, we will consider the stemplot or stem-and-leaf plot which can be used to arrange, analyse and interpret numerical data. Let’s consider a random sample of 20 concentrations of calcium carbonate CaCO 3 in milligrams per plott. That column contains what are called depths.

That is, the median of the 20 lea is Data valuesand are recorded as shown below: The depths column contains something a little different here, namely the 7 with parentheses around it.

Data are generally organized so that the leaf entries go from smallest to largest. Then we construct an ordered stemplot from the unordered version by arranging the leaves in ascending order.

Then, Minitab starts accumulating from the bottom of the plot. So, the median of the data set is The leaf represents digits in the units place.

For example, the first number in the depths column is a 1. We could divide 85 into a stem of 8 and a leaf of 5.

### Stem-and-Leaf Plots | STAT /

The depths are the frequencies accumulated from the top of the plot and the bottom of the plot until they converge in the middle. It arranges the data set in ascending order while retaining all the original data values. The stemplot for the data consisting of outliers can be displayed as follows: In our previous example, the median of the 64 IQs is Let’s take the efficient route, as most anyone would likely taken in practice, by letting Minitab generate the orderred for us:.

Here’s what Minitab’s stem-and-leaf plot of the 64 IQs looks like:.

### Stem and leaf plot

The stemplot for the data consisting of outliers can be displayed as follows:. Minitab unprdered us that the leaf unit is 0. For example, note that the first 9 row contains the 0 to 4 leaves, while the second 9 row contains the 5 to 9 leaves.

Our IQ data set produces stems 6, 7, 8, 9, 10, 11, 12, 13, and Create a stem-and-leaf plot of the data.

Bayesian Methods Section