Standard Deviation

Standard Deviation

Cornell Notes pages 124-125

​Essential Question: How can I describe the spread of a data set?

​Notes: on page 124

Standard Deviation : describes the spread of the data.

Standard Deviation also describes the variation(difference) of the data.

 

 

The higher the spread, the higher the standard deviation, the more

variability.

 

 

The lower the spread the data, the lower the standard deviation, the

less variability.

​Where to find

Standard Deviation in Desmos:

​

​1. Open up keyboard at the bottom of screen

​2. Click on functions in the bottom right corner

​3. Select the Stats tab

​4. Select stdev

​Example 1 page 124

​First step is to find the mean, range, standard deviation and interquartile range of original data 7,9,10,8,4,2,6,10,8.

​****Write these numbers in your book

​

​Second step is to add 9 to the original score and find the new mean, range, standard deviation and interquartile range

​****Write these numbers in your book

Fill in the Blanks

Example 1: A. What is the mean of your original data?

***Remember the write 3 #'s behind decimal if necessary***

​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select Mean and copy and paste data

Fill in the Blanks

Example 1: B. What is the range of your original data?

Find range on page 120

***Remember the write 3 #'s behind decimal if necessary***

​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select max and copy and paste data

​5. Create new line and select min and copy and paste data

​4. To find range subtract Max and min

Fill in the Blanks

Example 1: C. What is the standard deviation of your original data?

***Remember the write 3 #'s behind decimal if necessary***

​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select stdev and copy and paste data

Fill in the Blanks

Example 1: D. What is the interquartile range of your original data?

Find IQR on page 121

***Remember the write 3 #'s behind decimal if necessary***

​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select quartile and copy and paste data, don't forget ([data],1) for quartile 1

​5. Create new line and select quartile and copy and paste data, don't forget ([data],3) for quartile 3

​4. To find interquartile range subtract quartile 3 and quartile 1

Fill in the Blanks

Example 1: A. What is the mean of your new data?

***Remember the write 3 #'s behind decimal if necessary***

​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select Mean and copy and paste data

Fill in the Blanks

Example 1: B. What is the range of your new data?

Find range on page 120

***Remember the write 3 #'s behind decimal if necessary***

​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select max and copy and paste data

​5. Create new line and select min and copy and paste data

​4. To find range subtract Max and min

Fill in the Blanks

Example 1: C. What is the standard deviation of your new data?

***Remember the write 3 #'s behind decimal if necessary***

​​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select stdev and copy and paste data

Fill in the Blanks

Example 1: D. What is the interquartile range of your new data?

Find IQR on page 121

***Remember the write 3 #'s behind decimal if necessary***

​​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select quartile and copy and paste data, don't forget ([data],1) for quartile 1

​5. Create new line and select quartile and copy and paste data, don't forget ([data],3) for quartile 3

​4. To find interquartile range subtract quartile 3 and quartile 1

Multiple Choice

Example 1: Which of the following is NOT true

• A. The mean increases

• B. The range increases

• C. The standard deviation decreases

• D. The interquartile range decreases

​Example 2 page 124

​First step is to find the standard deviation, interquartile range, range and mean

​****Write these numbers in your book

​

​Second step is to add 45 to your original data and find the standard deviation, interquartile range, range and mean

​****Write these numbers in your book

Fill in the Blanks

Example 2: A. What is the standard deviation of the original data?

​​​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select stdev and copy and paste data

Fill in the Blanks

Example 2: B. what is the interquartile range of original data?

​​​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select quartile and copy and paste data, don't forget ([data],1) for quartile 1

​5. Create new line and select quartile and copy and paste data, don't forget ([data],3) for quartile 3

​4. To find interquartile range subtract quartile 3 and quartile 1

Fill in the Blanks

Example 2: C. What is the range of the original data?

​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select max and copy and paste data

​5. Create new line and select min and copy and paste data

​4. To find range subtract Max and min

Fill in the Blanks

Example 2: D. What is the mean of the original data?

​​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select Mean and copy and paste data

Fill in the Blanks

Example 2: A. What is the standard deviation of the new data?

​​​​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select stdev and copy and paste data

Fill in the Blanks

Example 2: B. What is the interquartile range of new data?

​​​​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select quartile and copy and paste data, don't forget ([data],1) for quartile 1

​5. Create new line and select quartile and copy and paste data, don't forget ([data],3) for quartile 3

​4. To find interquartile range subtract quartile 3 and quartile 1

Fill in the Blanks

Example 2: C. What is the range of the new data?

​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select max and copy and paste data

​5. Create new line and select min and copy and paste data

​4. To find range subtract Max and min

Fill in the Blanks

Example 2: D. What is the mean of the new data?

​​​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select Mean and copy and paste data

Multiple Select

Expmple 2: What would happen to the data set if Myrtle Beach was added?

• A. The standard deviation decreases

• B. The range decreases

• C. The interquartile range decreases

• The mean increases

Multiple Choice

Example 3: Which set of data would you expect to have the greatest standard deviation?

**Hint thing about the one that would have to largest range of data or different numbers****

• the heights in cm of all the studenst in the first grade classes in a large elementary school

• the heights in cm of all the first grade teachers in the elementary school

• the heights in cm of all the first grade students and all the first grade teachers in the elementary school

• the circumference in cm of the wrists for all the students in your class.

Multiple Choice

Example 4 on page 124: Which manufacturer has the least variability in their bricks? **Think of the one who's numbers are the least spread out***

• Adam's

• Bob's

• Camille's

• Daniel's

​Example 5 page 125

​First step is to find the standard deviation, interquartile range, mean and range

​****Write these numbers in your book

​

​Second step is to add 70 to the original data and find standard deviation, interquartile range, mean and range

​****Write these numbers in your book

Fill in the Blanks

Example 5: A. What is the standard deviation of the original data?

​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select stdev and copy and paste data

Fill in the Blanks

Example 5: B. What is the interquartile range of the original data?

​​​​​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select quartile and copy and paste data, don't forget ([data],1) for quartile 1

​5. Create new line and select quartile and copy and paste data, don't forget ([data],3) for quartile 3

​4. To find interquartile range subtract quartile 3 and quartile 1

Fill in the Blanks

Example 5: C. What is the mean of the original data?

​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select Mean and copy and paste data

Fill in the Blanks

Example 5: D What is the range of the original data?

​​1. Type in your data into desmos

​2. Select keyboard at bottom left

​3. Select Functions then stats

​4. Create new line and select max and copy and paste data

​5. Create new line and select min and copy and paste data

​4. To find range subtract Max and min

Fill in the Blanks

Example 5: A. What is the standard deviation of new data?

Fill in the Blanks

Example 5 B. What is the mean of the new data?

Fill in the Blanks

Example 5 C: What is the mean of the new data?

Fill in the Blanks

Example 5 D What is the range of the new data?

Multiple Choice

Example 5: What would happen to the data set?

• The standard deviation increases

• The interquartile range decreases

• The mean increases

• The range decreases