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what is the mean absolute deviation for the following(you don't need to show work): 7 6 8 5 1 6, 7 9 6 4 5 4, 4 5 6 6 9 2 3.

User Peshmerge
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Answer:

the average distance between each data point and the mean. It gives us an idea about the variability in a dataset.

Here's how to calculate the mean absolute deviation.

Step 1.Calculate the mean.

Step 2: Calculate how far away each data point is from the mean using positive distances. These are called absolute deviations.

Step 3: Add those deviations together.

Step 4: Divide the sum by the number of data points.

Following these steps in the example below is probably the best way to learn about mean absolute deviation, but here is a more formal way to write the steps in a formula:

\text{MAD}=\dfrac{\sum{\lvert x_i-\bar{x} \rvert}}{n}MAD= ∑∣ xi -x /n

start text, M, A, D, end text, equals, start fraction, sum, open vertical bar, x, start subscript, i, end subscript, minus, x, with, \bar, on top, close vertical bar, divided by, n, end fraction

Example

Erica enjoys posting pictures of her cat online. Here's how many "likes" the past 666 pictures each received:

10, 15, 15, 17, 18, 21

Find the mean absolute deviation.

Step 1: Calculate the mean

The sum of the data is 96 total "likes" and there are 6 pictures.

\text{mean}=\dfrac{96}{6}=16

mean= 96/6=16

start text, m, e, a, n, end text, equals, start fraction, 96, divided by, 6, end fraction, equals, 16

The mean is 16

Step 2: Calculate the distance between each data point and the mean.

Data point Distance from mean

10 |10-16|=6

15 |15-16|=1

15 |15-16|=1

17 |17-16|=1

18 |18-16|=2

21 |21-16|=5

Step 3: Add the distances together.

6+1+1+1+2+5=16

Step 4: Divide the sum by the number of data points.

\text{MAD}=\dfrac{16}{6}\approx2.67MAD=

MAD=16/6 =2.67 Likes

On average, each picture was about 333 likes away from the mean.

User Dave Forgac
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