Data Analysis

Median: 
Mean: 
Standard deviation: 
Range: 
        

Explanations

Here, you'll be able to find the vocabulary that is used, with some example.

Every example will use this set of data:

92 67 14 34 55 99 51 5 42 38

Mean

mean = average

→ It's the exact same!

The mean is the sum of every values divided by the number of values.

Example

(92 + 67 + 14 + 34 + 55 + 99 + 51 + 5 + 42 + 38) / 10 = 49.7

Median

First, you have to sort the data in ascending order (from smallest to largest).

In fact, you can sort it into descending order, it just that the you need your data in ascending for other stuff, like the quartiles for example.

The median is the middle value. So, if there is an odd number of values, it's possible. But when there isn't, you have to take the 2 middle values, and get the average of them.

The median is the same as Q2.

Standard deviation

To get the standard deviation, you first need to find the mean.

Once you have the mean, you need to get the square root of the mean of the squares of the difference between each mean and the number. Didn't understand a thing? Have a look at this:

Example

mean = 49.7
squares' sum = (49.7 - 92)² + (49.7 - 67)² + (49.7 - 14)² + ...
squares' mean = squares' sum / 10

standard deviation = sqrt(squares' mean)
            

Range

The range is easy. It's the largest value minus the smallest one

Example

99 - 5 = 94

Made with ♥ by @math2001