1. 2.6 Measures of Spread

2. Measures of Spread Measures or Spread Vs. Central Tendency

3. Deviation

4. Standard Deviation A “cool” way of finding the average of the deviations. Ideas on how?

5. Population Standard Deviaiton

6. Sample Standard Deviation

7. Example Use means and standard deviations to compare the heights of the 2 basketball teams. FalconsRavens PlayerHeight (cm)PlayerHeight (cm) Laura183Sam166 Jamie165Shannon163 Deepa148Tracy168 Colleen146Claudette161 Ingrid181Maria165 Justiss178Amy166 Sheila154Selena166

8. Standard Deviation FalconsHeightDeviation, x-µ(x-µ) 2 Laura183 Jamie165 Deepa148 Colleen146 Ingrid181 Justiss178 Sheila154 SUM

9. Standard Deviation RavensHeightDeviation, x-µ(x-µ) 2 Sam183 Shannon165 Tracy148 Claudette146 Maria181 Amy178 Selena154 SUM

10. Box and Whisker Plot Divided the data into 4 equal groups. Uses Medians 1 st quarter, second quarter, third quarter, fourth quarter

11. Example A random Survey of people at a science-fiction convention asked them how many times they had seen Star Wars. The results are as follows. 3 4 2 8 10 5 1 15 5 16 6 3 4 9 12 3 30 2 10 7 Make Box and Whisker Plot

12. Assignment Pg 148 #’s 1-3,6,7