Outliers

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

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

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

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

Find the 5 Number Summary of the following numbers: Step 1: Sort the numbers from lowest to highest Step 2: Identify the Median Step 3: Identify the Smallest and Largest numbers 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

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

Find the 5 Number Summary for the following set of data: Median Smallest Largest Median

Find the 5 Number Summary for the following set of data: Median = 10.5 Smallest = 2 Largest = 21 Median = 5.5 Median =

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

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

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 Q = 8

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

IQR = OUTLIER

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