1. Outliers

2. Do Now Bill Gates makes $100 thousand a year. He s in a room with 9 teachers, 4 of whom make $40k, 3 make $45k, and 2 make $55k a year. What is the mean salary of everyone in the room? What would be the mean salary if Gates wasn t included? Mean With Gates: $50,500 Mean Without Gates: $45,000

3. 312740914181517 Find the mean and median of the following set of numbers: Mean is 15 Median is 14

4. In a set of numbers, a number that is much LARGER or much SMALLER than the rest of the numbers is called an Outlier.

5. To find any outliers in a set of data, we need to find the 5 Number Summary of the data.

6. Find the 5 Number Summary of the following numbers: 312740914181517 Step 1: Sort the numbers from lowest to highest 379121415171840 Step 2: Identify the Median 379121415171840 Step 3: Identify the Smallest and Largest numbers 379121415171840 Step 4: Identify the Median between the smallest number and the Median for the entire set of data, and between that Median and the largest number in the set. 379121415171840

7. These are the five numbers in the 5 Number Summary 3 - Smallest number in the set 9 - Median between the smallest number and the median 14 - Median of the entire set 17 - Median between the largest number and the median 40 - Largest number in the set 379121415171840

8. Find the 5 Number Summary for the following set of data: 42 16 38 50 24 29 41 36 18 4 33 37 24 27 45 4 16 18 24 27 29 33 36 37 38 41 42 45 50 Median Smallest Largest Median 4 33 24 50 39.5

9. Find the 5 Number Summary for the following set of data: 4 8 2 19 11 6 21 13 5 7 10 20 14 15 18 3 Median = 10.5 Smallest = 2 Largest = 21 Median = 5.5 Median = 16.5 2 3 4 5 6 7 8 10 11 13 14 15 18 19 20 21

10. A 5 Number Summary divides your data into four quarters. 379121415171840 1 st Quarter 2 nd Quarter 3 rd Quarter 4 th Quarter

11. 379121415171840 The Lower Quartile (Q1) is the second number in the 5 Number Summary The Upper Quartile (Q3) is the fourth number in the 5 Number Summary 25% of all the numbers in the set are smaller than Q1 25% of all the numbers in the set are larger than Q3

12. 379121415171840 What percent of all the numbers are between Q1 and Q3? 50% of all the numbers are between Q1 and Q3 This is called the Inter-Quartile Range (IQR) The size of the IQR is the distance between Q1 and Q3 17 - 9 = 8

13. 379121415171840 IQR = 8 To determine if a number is an outlier, multiply the IQR by 1.5 8 1.5 = 12 An outlier is any number that is 12 less than Q1 or 12 more than Q3

14. 379121415171840 IQR = 8 + 12- 12 - 3 39 OUTLIER

15. 312740914181517 Find the mean and median of the following set of numbers (no outliers): Mean is 15 Median is 14 Mean is 11.875 Median is 13