1. 3.3 – Percentiles & Box-and-Whisker Plots Mean and Standard Deviation deal with exact numbers to measure. Sometimes measuring position is important too. Percentiles Quartiles

2. Percentile For whole numbers P (where 1 ≤ P ≤ 99), the Pth percentile of a distribution is a value such that – P% of the data fall at or below it and – (100-P)% of the data fall at or above it. Why 99 Births

3. Guided Exercise #6 As whole group, turn to page 99 – Whole group clarification

4. Quartiles

5. How to Compute Quartiles 1.Order data from smallest to largest 2.Find Q2 (Median) – Median of all data – Middle data (odd), or average if 2 data (even) 3.Find Q1 – Median of lower half of data (not including Q2) 4.Find Q3 – Median of upper half of data (not including Q2) Find 3 medians

6. Guided Exercise #7 With Whole Group, turn to page 102 – Cover answers – Discuss answers Check – Whole group clarification

7. Guided Exercise #7 342377319353295 234294286377182 310439111201182 197209147190151 131151 111131147151 182 190197201 290234286294295 310319342353377 439

8. Box-and-Whisker Plots A visual representation of our Quartiles – Remember…Positioning Five-Number Summary: Lowest value, Q1, Q2 (Median), Q3, Highest value

9. Create Box-and-Whisker Plots Use the Five-Number Summary: Lowest value, Q1, Q2 (Median), Q3, Highest value *| | |* 1.Draw a vertical (or horizontal) scale including highest and lowest data values (spacing) 2.Draw box from Q1 to Q3 3.Include solid line through box at median 4.Draw lines “whiskers” from box to lowest and highest values.

10. Try it… In Algebra 1 Core, my last test scores were: 4247545556374031 4055444058335557 5842423340 Make a box-and-whisker plot

11. Expand Your Knowledge Outliers: Lower Limit: Q1 – 1.5(IQR) Upper Limit: Q3 + 1.5(IQR)

12. Checkpoint  Interpret meaning of percentile score  Compute the five-number summary from raw data  Make box and whisker plot, and interpret results  Describe how box and whisker plot indicates spread

13. Homework Read Pages 98-105 – Take notes on what we have not covered Do Problems – Page 106-108 (1-10) Check odds in back of book Check all on website Get Ready for Test Chapter Review Problems – Notes/vocab