Mean Absolute Deviation - M.A.D.

Finding the Mean Absolute Deviation (MAD)
Step 1: Find the mean of the data.
Step 2: Find the distance between each data value and the mean.
Step 3: Find the sum of the distances in Step 2.
Step 4: Divide the sum in Step 3 by the total number of data values.

 

Quartiles and Interquartile Range

1. Order the Data from least to greatest
2. Find the median
3. Split the data in half, lower half and upper half
4. First Quartile- Find the median of the lower half
5. Third Quartile - Find the median of the upper half
6. The interquartile range- Take the third quartile and subtract the first quartile

**Quartiles show the spread of data

Range

Class Song for Range:

Home Home on the Range,

Take the High and subtract the Low

The data is spread 

a variation you see

Now, you are all as smart as me

Team one range: 78-72 = 6

Team two range: 84-67= 17

Team one has a difference of 6 inches between their players.

Team two has a difference of 17 inches between their players. 

Median and Mode

_________________________________

Mode is 6

_______________

There can be many modes or No modes!!!!!!

 - - - - - - - - - - - - - - - - - - - - - - - - - - - 

_________

________

_________

If there are 2 numbers in the middle 

Add the two numbers together

and divide by 2

_________

___________

Mean

64 + 77 + 79 + 80 + 84 + 86 + 90 + 90 + 94 + 96 + 97 + 98 =1035

1035 divided by 12 = 86.25

Compare two means

Team 1: 72 + 73 + 76 + 76 + 78 = 375

375 divided by 5 = 75 inches

Team 2: 67 + 72 + 76 + 76 + 84 = 375

375 divided by 5 = 75 inches

The two teams have the same mean!

Outlier affects the mean

Mean with the outliers: 35

Mean without the outliers: 25

With the outlier, the mean is a lot higher than without the outlier.  

The mean is best represented without the outlier. 

Dot Plots/ Line Plots

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Distribution of Data

Cluster- where several data points are together

Gap- an interval with no data

Peak- data value that occurs most often

Outlier- One data point by itself, away from the cluster

**** You can have zero, one, or more clusters, peaks, or gaps

Statistical Questions

 

Statistical Questions are like those found on a survey. 

They provide a variety of answers. 

Examples: 

What is your shoe size?

What is your favorite food? 

How much does your dog weigh?

Not Statistical Questions:

What year did Tonaquint open? 

How many United States Presidents have there been?