finding interquartile range from stem-leaf plot 2
Post on 21-Jul-2015
174 Views
Preview:
TRANSCRIPT
- Mr Kim
Finding IQR for even number of scores
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
First, find the Median by crossing off the scores
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Now, start by crossing off the Smallest Number
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
2
Now, start by crossing off the Smallest Number
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Now cross off the Biggest Number
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 747
Now cross off the Biggest Number
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Cross off the scores in the directions shown
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
“In”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
“Out”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
“In”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Notice there is nothing in the 30’s
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
So skip to the next score
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
“Out”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
“In”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
“Out”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
“In”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
“Out”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Stop here
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Always stop at “Out”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Put a line between the two scores
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Put a line between the two scores
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
12
11
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
So the Median (Q2) is in between 11 and 12
which is …
12
11
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
So the Median (Q2) is in between 11 and 12
which is 11.5
11
12
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
So the Median (Q2) is in between 11 and 12
which is 11.5
11+122
11
=11.5
12
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Now find the Lower and Upper Quartile by dividing the Stem-Leaf Plot in two
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
**It is very important to divide the sides properly
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
To do this, count the scores from the start
until you reach the Line
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Stop here!
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Now put a Border around the scores that you just
counted
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Now put a Border around the other side
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
This is how you correctlydivide the sides
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Now find the Median for both sides of the scores by crossing off each side at a
time
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
We will start with this side
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Remember the directions
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
“In”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
“Out”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
“In”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
“Out”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Stop here!
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
43
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
So the Lower Quartile (Q1)is between 3 and 4
which is …
43
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
43
So the Lower Quartile (Q1)is between 3 and 4
which is 3.5
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
43
So the Lower Quartile (Q1)is between 3 and 4
which is 3.5
3+42
= 3.5
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
Now cross off the other side
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
Remember the directions
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
“In”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
“Out”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
“In”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
“Out”
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
Stop here!
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
2320
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
So the Upper Quartile (Q3)is between 20 and 23
which is …
2320
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
So the Upper Quartile (Q3)is between 20 and 23
which is 21.5
2320
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
So the Upper Quartile (Q3)is between 20 and 23
which is 21.5
2320
20+232
= 21.5
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
Upper Quartile: 21.5
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
So, the Interquartile Range is
Upper Quartile: 21.5
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
So, the Interquartile Range is
Upper Quartile: 21.5
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
Upper Quartile: 21.5
So, the Interquartile Range is21.5 –
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
Upper Quartile: 21.5
So, the Interquartile Range is21.5 –
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
Upper Quartile: 21.5
So, the Interquartile Range is21.5 – 3.5
0 2 2 3 4 6
1 1 2
2 0 0 3
3
4 5 7
Lower Quartile: 3.5
Upper Quartile: 21.5
So, the Interquartile Range is21.5 – 3.5 = 18
Our Final Answer!
top related