1. Shape, Center, Spread

2. The distribution of a set of data describes the arrangement of data values
Can be described by:
Shape
Center
Spread

3. Shape

4. Examples
A. B.
Skewed right Symmetric
C. D.
Skewed right Symmetric

5. Center What is the center? What is it called? 80, Median
Other ways to find center:
Mean, Mode
These are called MEASURES OF CENTRAL TENDENCY
They tell us the EXPECTED MIDDLE VALUE for the data set
In general…
• IF the data is symmetric, the MEAN is the best measure of central tendency.
• IF the data is skewed left or right, the MEDIAN is the best measure of central tendency.

6. Spread Spread refers to HOW FAR APART the data is
How can we find this information out? STANDARD DEVIATION, IQR, RANGE
What is the range of this data: 35
What is the IQR: 20

7. In summary Symmetric Distribution Skewed Distribution
Measure of Center
Mean
Median
Measure of Spread
Standard Deviation
IQR/Range