1. Statistics: Use Graphs to Show Data Box Plots.
Welcome to Math 6
Statistics:
Use Graphs to Show Data
Box Plots.

2. Objectives
Interpret graphs that show the shape of a distribution of data.
Discuss the center, spread and overall shape with dot plots, histograms and box plots.

3. Box (and Whisker) Plot
The box plot is constructed from the five-number summary:
minimum
lower quartile
median
upper quartile
maximum
These values give a summary of the shape of a distribution.

4. Key Vocabulary Box plot (box and whisker graph)
A graph that shows how far apart and how evenly data are distributed.

5. Box (and Whisker) Plot
Advantages:
This graph can be used for very large data sets because it gives a general idea of how the data is clustered together. Exact values of each data point are not given in a box plot.

6. Box (and Whisker) Plot
A further advantage is that additional box plots can be drawn above (or below) the same number line to compare two or more data sets.

7. Box (and Whisker) Plot
Box plot visually displays a distribution of data values by using the median, quartiles, and extremes of the data set.
The box shows the middle 50% of the data and the extended “whiskers” show the remaining 50% of the data.

8. Key Vocabulary
Variability- is another characteristic of a data set. It also known as the ‘spread’ of the values.

10. Key Vocabulary
Upper Extreme
The largest number in a set of data.

11. Key Vocabulary
Lower Extreme
The smallest number in a set of data.

12. Key Vocabulary Upper Quartile (Third Quartile)
The number that three quarters of the data in the list are below.

13. Key Vocabulary Lower Quartile (First Quartile)
is a number that one quarter of the data in the list are below it.

14. Key Vocabulary Second Quartile (Median)
The number that divides the data into a lower and an upper half. The second quartile is the same as the median.

15. Interquartile range- Difference between
the first and third quartiles in a data set.

16. Creating a Box Plot (Box and Whisker Plot)
1) Write the data in order from least to greatest.
2) Draw a horizontal number line that can show the data in equal intervals.
3) Find the median of the data set and mark it on the number line.

17. Creating a Box Plot (Box and Whisker Plot)
4) Find the median of the upper half of the data. This is called the upper quartile. Mark it on the number line. 5) Find the median of the lower half of the data. This is called the lower quartile. Mark it on the number line. 6) Mark the lower extreme (minimum) on the number line.

18. Creating a Box Plot (Box and Whisker Plot)
7) Mark the upper extreme (maximum) on the number line. 8) Draw a box between the lower quartile and the upper quartile. Draw a vertical line through the median to split the box.

19. 9) Draw a “whisker” from the lower quartile to the lower extreme.
10) Draw a “whisker” from the upper quartile to the upper extreme

20. Guided Practice
Draw a box-and-whisker plot for the set of data below. Baseball Games Won by Teams in National League,

21. 2. Describe the data values that are located in the box of a
Guided Practice
2. Describe the data values that are located in the box of a
Box-and-Whisker plot.

22. CONCLUSION
To make a Box-and-Whisker Plot , draw a box around the quartile values, and lines or whiskers to represent the values in the lower fourth of the data and the upper fourth of the data.

23. box plots, dot plots, histograms, frequency tables, cluster, peak, gap, mean, median, interquartile range, measures of center, measures of variability, data, Mean Absolute Deviation (M.A.D.), quartiles, lower quartile (1st quartile or Q1), upper quartile (3rd quartile or Q3), symmetrical, skewed, summary statistics, outlier

24. Assignments Try some extra practice
making and interpreting Box Plots on the attached homework assignment.