7.SP.B4 Using variability measures of random samples to compare

Using variability measures of random samples to compare two populations

Standard 7.SP.B.4

REVIEW!!!!
Mean Absolute Deviation

An acronym used is MAD

M = Mean

A= Absolute

D= Deviation

Multiple Choice

What does the "M" stand for in MAD?

• Mean

• Median

• Mode

• Multiply

Open Ended

Recall all the math you have learned so far. When did we use the word 'Absolute'?

We have learned about the word ABSOLUTE before

OH YEAH. ABSOLUTE VALUE!!!

What does absolute value mean again?

​

M

ABSOLUTE

D

Multiple Choice

Absolute value means to find the ________ from zero.

• Mean

• Median

• Mode

• Distance

Means to find the distance from the mean!

The Absolute in MAD

Means to find the distance a number is from zero

Absolute Value

What does absolute have to do with MAD process?

Draw

Show the distance between 3 and 8

DEVIATION refers to how spread out data is.

Multiple Choice

What does Mean Absolute Deviation mean?

• The distance from zero data is

• The average of a set of numbers

• The distance data is from the mean that tells how spread out data is

• A summary of a given data set using mean, median, mode

M = Find the Mean

A = Find the distance from the mean

D = Find the mean of the distances

Let's practice

Multiple Choice

What is the Mean Absolute Deviation of the following data set? (You have to find the mean first, then the distance from the mean, then find the mean of the distances)

3, 4, 4, 6, 8

• 5

• 1.6

• 25

• 2

Multiple Choice

What is the M.A.D of the following data if the mean is 87?

70, 82, 88, 90, 96, 96

• 7.3

• 3.7

• 44

• 87

Open Ended

A company gathers the salaries of all it's employees and calculates the M.A.D. They discover the M.A.D is $50,000. What do think this says about the salaries of the employees?

Multiple Choice

True or False: Mean Absolute Deviation will always be a whole number

• True

• False

Mean Absolute Deviation

• The average distance between the data values and the mean.

• Find the mean, then find the distance between the mean and each data value.

Example: Find the MAD of 10,12,18,11,19

• 10 + 12 + 18 + 11 + 19 = 70 so 70/5 = 14

• 14 - 10 = 4

• 14 - 12 = 2

• 14 - 18 = 4

• 14 - 11 = 3

• 14 - 19 = 5

• 4 + 2 + 4 + 3 + 5 = 18 so 18/5 = 3.6

Multiple Choice

Determine the mean absolute deviation of the data.
9, 7, 11, 10, 8

• 9
• 6
• 1.2
• 5

Multiple Choice

Find the Mean Absolute Deviation:  10, 9, 3, 8, 10.  The Mean is 8

• 3
• 5
• 1
• 2

Multiple Choice

Find the MAD:
58, 38, 54, 48, 26, 36

• 43
• 20
• 10
• 12

Graphing with Boxplots

Box plots are a way of representing the spread of data.

​

​Some text here about the topic of discussion.

Math Response

What is the range of the data?

Type answer here

Correct Answer: 10

Deg^°

Rad

Match

Match the following

• Range

• Interquartile Range (IQR)

• Q2

• Q1

• Q3

Max - Min

Q3 - Q1

Median

Median of the LOWER half

Median of the UPPER half

• Max - Min

• Q3 - Q1

• Median

• Median of the LOWER half

• Median of the UPPER half

How to read a box plot

​Minimum or smallest value

Maximum or largest value

​Range of data= Maximum-Minimum

Multiple Choice

What is the range of math quiz results from Mrs. Sanchez's class?

• 75

• 20

• 95

• 60

How to read a box plot

​median of all data

Multiple Choice

What is the median of math quiz results from Mrs. Sanchez's class?

• 50

• 63

• 70

• 75

Labelling

Drag the correct label to each value.

Drag labels to their correct position on the image

Med(Q2)

Max

Min

Q3

Q1

Math Response

What is the range of the data?

Type answer here

Correct Answer: 10

Deg^°

Rad

A statistical question....

• Requires you to gather data

• Is not a yes or no question

• One that can be answered by collecting multiple data and where there will be variability in that data.

Multiple Choice

Is the following question statistical or non statistical?
On average, how many water bottles does every class go through daily?

• Statistical
• Non Statistical

Multiple Choice

Is the following question statistical or non statistical?
How many cars are in the parking lot?

• Statsitical
• Non Statistical

Multiple Choice

Is the following question statistical or non statistical?
How tall are the students in our class?

• Statistical
• Non Statistical

Multiple Select

Group A and Group B were randomly sampled from the same population. Which statements below are true? Select all that apply.

• Group A has a greater median than Group B

• Group A has a greater range than Group B

• Group A has greater variability than Group B

• Group B has a greater median than Group A

• You cannot tell which group has the greater median based on the picture.

Multiple Choice

Kerron gathers the heights of a random sample of 6th graders and 7th graders and displays the data in box plots. Which statement below is true?

• The median of the 7th grade sample is greater than the 6th grade sample.

• The 7th grade sample has greater variability.

• The ranges of both data samples are equivalent.

• The median of the 6th grade sample is greater than the 7th grade sample.

Multiple Choice

Mario compares random download times of movies from three different services using the table shown. Which service provides the fastest mean download speed?

• WhoKnew

• Amazing Prime

• Peach TV

Multiple Choice

Harry collects data from a random sample of seventh-graders. Out of 25 respondents, 10 ride the bus to school. Out of 150 seventh-graders who attend Harry's school, how many would be expected to ride the bus to school?

• 40 seventh-graders

• 50 seventh-graders

• 60 seventh-graders

• 90 seventh-graders

Multiple Select

The drama teacher wants to determine where the drama club should go to celebrate their final performance. Which of the following is NOT a representative sample?

• Students who do not act.

• Every 4th student selected from an alphabetical roster of the club

• Students who appear in the first act

• Students with supporting roles

• Students whose names are randomly selected from a hat

Multiple Select

Which of the following measures of center can be used to compare two data sets? Select all that apply/

• mean

• interquartile range

• median

• mean absolute deviation (MAD)

• range

Multiple Choice

What do the box plots tell you about the growth of a typical plant species?

• B typically grows taller than A since the range for B is greater.

• B typically grows taller than A since the IQR for B is greater.

• A grows taller than B since the median for A is greater.

• A typically grows taller than B since the mean for A is greater.

Multiple Choice

What do the box plots tell you about the variability of the data?

• B has greater variability because its range and IQR are greater than A.

• B has greater variability because its median & mean are greater than A.

• A has greater variability because its range & IQR are greater than B.

• A has greater variability because its median and mean are greater than B.

Multiple Choice

What inference can be made about the populations based on Paisley's data?

• young teachers drive trucks

• SUVs are driven by teachers with families

• most teachers drive sedans

• fewer teachers drive sedans than SUVs

Multiple Choice

Which of the following measures CANNOT be made from a box plot?

• Interquartile Range

• Mean

• Median

• Range

Multiple Choice

Compare the variability of the data for each store.

• The range & IQR are greater at store B as compared to store A.

• There is less variability in prices of DVD players at store A.

• The range & IQR are greater at store A as compared to store B.

• There is more variability in prices of DVD players at store B.

Multiple Choice

_________ is a sample in which each individual or object in the entire population has an equal chance of being selected.

• Sample

• Population

• Random Sample

• Quartile

Multiple Choice

_______ is a part of a group being surveyed.

• Sample
• Population
• Random Sample
• Quartile

Multiple Choice

Why do we randomly select our samples?

• to control every aspect
• reduce bias
• so we don't get the same answers from everyone
• because it is easier to do

Multiple Choice

Darrien surveys 60 of the actors theater class. He concludes that 8 out of 15 actors have previous acting experience. What is the sample size?

• 60
• 8
• 15
• 53

Multiple Choice

Every member of the larger group has an equal chance of being chosen.

• secondary sample
• systematic sample
• stratified sample
• random sample

Multiple Choice

In order to use samples to estimate something from the population, the sample should be _________________ the population.

• exactly the same as
• nothing like
• representative of
• larger than

Multiple Choice

An entire group of objects - people, animals, plants - from which data can be collected.

• population

• sample

• representative sample

• random sample

Multiple Choice

_______ is the entire group of objects or individuals considered for a survey.

• Sample
• Population
• Random Sample
• Quartile

Multiple Choice

Interview the first 30 students who enter the school in the morning. 

• simple random
• population
• systematic
• convenience

Multiple Choice

Assign each car in a dealership a number and then use a random-number table to select the cars to be inspected. 

• systematic
• random sample
• convenience
• biased sampling

Multiple Choice

Why do we randomly select our samples?

• for control
• reduce bias
• so we don't get the same answers from everyone
• to eliminate confounding results