Central Tendency

Mean, Median, Mode, Range, Outlier

Objectives

SPI 0506.5.3 Calculate measures of central tendency to analyze data.Checks 0506.5.5 Evaluate how different measures of central tendency describe data. Checks 0506.5.6 Identify outliers and determine their effect on mean, median, mode and range.

Find the mean, median, mode, range, and outlier in a data set.

Did You Know…That you

probably use statistics such as mean, median, mode and range almost every day without even realizing it?!?

Today We Will Learn…

• Mean• Median• Mode• Range

And how to use these in everyday life, as well as the classroom!

What Do We Already Know?

Sure, the words “Mean, Median, Mode and Range” all sound confusing…

But what about the words we already know, like “Average, Middle, Most Frequent, and Difference”?

They are all the same ideas!

Teachers average your grades every 9 weeks

This is the same thing as finding the mean.

Video 18-00

• http://www.pearsonsuccessnet.com/snpapp/learn/navigateIDP.do?method=vlo&internalId=130511100000159

Central TendencyMean- (average) 1- add all of the scores together 2- count how many scores there are 3- Divide the sum by the # of scoresMedian- (middle #) 1- Put all of the scores in order from least to greatest 2- If there are an odd number of scores, the median will be the # in the middle 3- If there is an even number of scores, find the mean of the 2 numbers in the middle.Mode- (most often) 1- The mode is the number that appears most often in a set of data. 2- If all of the numbers only appear 1 time each, then there will be NO MODE. (*The

answer will not be 0 because 0 is a number).Range- (L to G)1- Put all of the scores in order from least to greatest (* which you already do this

to find the median) 2- What is the biggest #? What is the smallest #? 3- The range is the difference between the greatest # and least # in a set of data is

the range.Outlier- (a # that is just “out” on it’s own) A number which is far removed from the other numbers in a data set.

Students paste these notes in journal and write down the examples for each found on the following slides.

Mean- (Average) 1- add all of the scores together 2- count how many scores there are 3- Divide the sum by the # of scores Show your work here:

Find the mean, median, mode, and range of 2,8,3,8,4

Mean- (Average) 1- add all of the scores together 2- count how many scores there are 3- Divide the sum by the # of scores

Example: 2 + 8 + 3 + 8 + 4= 25 There are 5 scores 25 ÷ 5 = 5 Mean = 5

Find the mean, median, mode, and range of 2,8,3,8,4

Mean step by step basketball

• http://studyjams.scholastic.com/studyjams/jams/math/data-analysis/mean-average.htm

Find the mean, median, mode, and range of 2,8,3,8,4

Median- (Middle #)

1- Put all of the scores in order from least to greatest

2- If there are an odd number of scores, the median will be the # in the middle

3- If there is an even number of scores, find the mean of the 2 numbers in the middle.

Show your work here:

Find the mean, median, mode, and range of 2,8,3,8,4

Median- (Middle #) 1- Put all of the scores in order from least to greatest 2- If there are an odd number of scores, the median will be the # in the

middle 3- If there is an even number of scores, find the mean of the 2 numbers in

the middle.

Example 2,8,3,8,4 2,3,4,8,8 There is an odd # of scores, so the median is 4.

In order from Least to Greatest

Find the mean, median, mode, and range of 2,8,3,8,4

Mode- (Most Often) 1- The mode is the number that appears most often in a set of

data. 2- If all of the numbers only appear 1 time each, then there

will be NO MODE. (*The answer will not be 0 because 0 is a number).

show your work here:

Find the mean, median, mode, and range of 2,8,3,8,4

Mode- (Most Often) 1- The mode is the number that appears most often in a set of data. 2- If all of the numbers only appear 1 time each, then there will be NO

MODE. (*The answer will not be 0 because 0 is a number).

Example 2,3,4,8,8 Mode = 8

* if there had been 1 more 4 in this set of data the mode would have been 4 and 8.

Use what you just learned to Find the mean, median, and mode of the

following data: 19, 5, 20, 19, 19, 18, 5, 19, 20

Use what you just learned to Find the mean, median, and mode of the

following data: 19, 5, 20, 19, 19, 18, 5, 19, 20

in order from L to G: 5, 5, 18, 19, 19, 19, 19, 20, 20

mean= 5+5+18+19+19+19+19+20+20 = 144 144 ÷ 9 = 16 median = 19 (the # in the middle) mode= 19

Mean= 16 Median= 19 Mode = 19

Find the mean, median, mode, and range of 2,8,3,8,4

Range- 1- Put all of the scores in order from least to greatest (* which you already

do this to find the median) 2- What is the biggest #? What is the smallest #? 3- The range is the difference between the greatest # and least # in a set of

data is the range.

Find the range here:

Find the mean, median, mode, and range of 2,8,3,8,4

Range-

1- Put all of the scores in order from least to greatest (* which you already do this to find the median)

2- What is the biggest #? What is the smallest #? 3- The range is the difference between the greatest # and least # in a set of

data is the range.

Example: 2,3,4,8,8 Biggest # = 8 Smallest # = 2 8 – 2 = 6 Range = 6 or 2 to 6

Find the mean, median, mode, and range of 2,8,3,8,4

Outlier- A number which is far removed from the other

numbers in a data set. The data that is shown above (2,8,3,8,4) does not have an outlier because

all of the numbers are relatively close together.

What would the outlier be in the following set of data? 14, 12, 22, 7, 40, 5, 13, 14

Find the mean, median, mode, and range of 2,8,3,8,4

Outlier- A number which is far removed from the other

numbers in a data set. What would the outlier be in the following set of data?

14, 12, 22, 7, 40, 5, 13, 14If you said 40, then you are correct!

If we arranged these numbers on a number line or a line plot, 40 would be “out” on it’s own.

Practice on your own:

Textbook page 450 #11-22

**Students may use calculators on all problems for MMMRO

Homework

• Bowling averages worksheet

Objectives

SPI 0506.5.3 Calculate measures of central tendency to analyze data.Checks 0506.5.5 Evaluate how different measures of central tendency describe data. Checks 0506.5.6 Identify outliers and determine their effect on mean, median, mode and range.

Find the mean, median, mode, range, and outlier in a data set.

Textbook page 452 # 7=10

Yummy Central Tendency

You will be placed in a group.Each group will be stacking cookies to determine how many

they can stack before the stack falls.The # that should be used is the last one BEFORE the stack

falls. (Example: if you add your tenth cookie to the stack and it falls, then you would write down 9)

You will do this “test” 7 times; writing down the results from each stack.

After the 7th stack, your group will return to your desk and find the mean, median, mode, and range for your data.

At the end of class, one member from each group will record the group’s data on chart paper.

While waiting for your group to perform their test, all students should be working on WB pgs 275-278 .

Median, Mode, Range 18-08

• http://www.pearsonsuccessnet.com/snpapp/learn/navigateIDP.do?method=vlo&internalId=130511100000167

• If you need

Range step by step

• http://studyjams.scholastic.com/studyjams/jams/math/data-analysis/range.htm

Mean step by step 18-07

• http://www.pearsonsuccessnet.com/snpapp/learn/navigateIDP.do?method=vlo&internalId=130511100000166

• IF you need it