Standard Deviation Calculator

Formulas Used

Standard Deviation Formula

σ = √(Σ(x - μ)² / N)

Where:

σ = Standard Deviation

μ = Mean of the numbers

N = Total number of data points

Variance Formula

σ² = Σ(x - μ)² / N

The Standard Deviation Calculator is a useful tool. It helps identify numbers in a data set. This calculator tells us how much individual numbers in a set differ from the average or mean. The knowledge of standard deviation can help students, teachers, and professionals in many subjects, like Maths, Science, and Economics.

This article tells what the standard deviation is and how you can calculate it. You will also be able to differentiate between population and sample standard deviation.

JAIN (Deemed-to-be University) Standard Deviation Calculator

At JAIN (Deemed-to-be University), students can access the Standard Deviation Calculator online. The use of this calculator simplifies calculating standard deviation. It also gives accurate results. Standard deviation is a key concept in data analysis. The calculator helps students in the study of statistics. It also helps them with their assignments and projects.

What is the Standard Deviation?

To begin, let’s understand what is the standard deviation. In simple terms, it is a number that shows how much the values in a set of data vary from the mean or average. When the numbers are close to the average, the standard deviation is small. But if the numbers are spread out far away from the average, the standard deviation is large. A low standard deviation means the values are similar, while a high standard deviation means there is a lot of difference.

How to Calculate Standard Deviation

If you want to know how to calculate standard deviation, here is a step-by-step process. Don’t worry; we will keep it simple!

  1. Find the mean: Add up all the numbers in your data set and divide by how many numbers there are.

Formula:

Mean=Sum of all valuesNumber of values\text{Mean} = \frac{\text{Sum of all values}}{\text{Number of values}}Mean=Number of valuesSum of all values​

  1. Subtract the mean from each number: This tells you how far each number is from the average.

  2. Square the result: To make sure the differences are positive, square each result. This step helps in making negative numbers become positive.

  3. Find the average of these squared differences: Add all the squared differences together and divide by how many numbers there are.

  4. Take the square root: Finally, take the square root of the result to get the standard deviation.

The formula for the standard deviation equation looks like this:

Standard Deviation=∑(Xi−μ)2N\text{Standard Deviation} = \sqrt{\frac{\sum{(X_i - \mu)^2}}{N}}Standard Deviation=N∑(Xi​−μ)2​​

In the above standard deviation equation:

  • XiX_iXi​ represents each value in the data set

  • μ\muμ is the mean

The Standard Deviation Formula

As mentioned earlier, the standard deviation formula is important for calculating the spread of data. The formula involves calculating the mean, finding the differences from the mean, squaring them, averaging, and then taking the square root.

There are different versions of the standard deviation formula for different situations. The formula used for a population is slightly different from the formula for a sample. Let’s look at that.

Population vs Sample Standard Deviation Formula

When you calculate the standard deviation for an entire population, you use one formula. But if you are working with a sample (a smaller part of the population), you need a slightly different approach. The population standard deviation formula divides by the total number of values, while the sample standard deviation formula divides by the number of values minus 1. This difference helps make the sample standard deviation a better estimate for the population’s standard deviation.

Here are both formulas:

  • Population Standard Deviation: σ=∑(Xi−μ)2N\sigma = \sqrt{\frac{\sum{(X_i - \mu)^2}}{N}}σ=N∑(Xi​−μ)2​​

Standard Deviation Examples

To make things clearer, let’s go through a standard deviation example. Imagine you have this data set: 2, 4, 6, 8, 10.

Step 1: Find the mean
Mean = (2 + 4 + 6 + 8 + 10) ÷ 5 = 30 ÷ 5 = 6

Step 2: Subtract the mean from each value
2 - 6 = -4
4 - 6 = -2
6 - 6 = 0
8 - 6 = 2
10 - 6 = 4

Step 3: Square the differences
(-4)² = 16
(-2)² = 4
(0)² = 0
(2)² = 4
(4)² = 16

Step 4: Average the squared differences
(16 + 4 + 0 + 4 + 16) ÷ 5 = 40 ÷ 5 = 8

Step 5: Take the square root
√8 ≈ 2.83

So, the standard deviation of this data set is approximately 2.83.

Using a Standard Deviation Calculator

Using a Standard Deviation Calculator is very easy and quick. All you need to do is enter the data into the calculator, and it will give you the result in seconds. This is a great way to avoid doing all the steps manually, especially when you have a large data set.

You now have the knowledge of standard deviation calculator, the standard deviation formula, and how to calculate standard deviation. You also explored the difference between the population vs sample standard deviation formula and went through a simple standard deviation example. Whether you’re working on school homework, a project, or just curious about numbers, understanding standard deviation can help you make sense of data and understand how spread out the values are.

Now, with the help of a Standard Deviation Calculator, you can easily find the standard deviation for any data set and learn more about how numbers are related. 

FAQs

What is standard deviation?

Standard deviation is a measure of how spread out the numbers in a data set are. It shows how much the numbers differ from the average.

How to calculate standard deviation?

To calculate standard deviation, find the mean, subtract the mean from each number, square the differences, find the average of those squared differences, and then take the square root.

Why standard deviation is used?

Standard deviation is used to understand how much variation or spread there is in a data set. It helps compare how different data points are from the average.

What is standard deviation formula?

The formula for standard deviation is:

σ=∑(Xi−μ)2N\sigma = \sqrt{\frac{\sum{(X_i - \mu)^2}}{N}}σ=N∑(Xi​−μ)2​​

Where XiX_iXi​ is each data point, μ\muμ is the mean, and NNN is the total number of values.