It is not easy to analyze large amount of data by manually. So, for resolving these kind of problems, we use graphical, statistical and Probability methods, which are called as a steam and leaf plot. With the help of stem leaf plot, we can easily find out relative density and value of particular data, means we can easily summarize data with the help of stem and leaf plot. Now we will discuss method for creating stem and leaf plot:
We use following steps for creating the stem and leaf plot -
Step 1: First of all, we will analyze all the data values, like if we have data values from 25 to 100, then we can calculate any number which repeats itself or not and if number is repeated then how many times it repeats itself.
Step 2: Now if we take tenth digit, like we have 61, then we take 6 this tenth digit is called as a stem.
Step 3: After evaluation of stem, now we calculate all values which are related with stem like we have 42 43 47 49 as a data values, then we have 4 as a stem and 2, 3, 7, 9 are values which are related with stem and these data values which are related with stem is called as leaf.
Suppose we have following data values -
22 25 28 44 49 35 67 63 69 71 73 78
Step 1: First of all we analyze these Numbers -
Here no number is repeating itself, so, we will go to next step.
Step 2: Now we will evaluate stem value from above data values -
Are stem values because these values are tenth digit values from above data values.
Step 3: Now we evaluate all values which are related with stem means here we evaluate leaf values -
2 = 2 5 8,
3 = 5,
4 = 4 9,
6 = 3 7 9,
7 = 1 3 8,
So, right hand side values are called as a leaf values because they are related with stem, which are shown on left hand side. Therefore this method is called as stem and leaf plots.