Standard Deviation Binomial Distribution: Overview
A binomial distribution is one of the simplest types of distributions in statistics. It’s a type of distribution where there is either success, or failure. For example, winning the lottery: or not winning the lottery. Most elementary statistics classes require you to find the standard deviation of the binomial distribution. This can be a challenge, because the variance and standard deviation formulas are daunting when you first look at them. However, if you break the formulas down into steps, they don’t look as scary. This how to will tell you how to find a standard deviation binomial distribution in just a few steps.
Standard Deviation Binomial Distribution: Steps
- Step 1: Find the mean. If you don’t know how to find the mean, see how to find the mean of the probability distribution.
- Step 2: Square the mean from step 1. For example, if your mean is .9, .9²=.81. Set this number aside for a moment.
Step 3: Make a probability distribution chart. If you’re not sure how to make one, see: How to construct a probability distribution.
- Step 4: Square the top number (X) in each column and multiply it by the bottom number in the column (P(X)). For example 0²*0.09 from the first column, 1²*0.07. Repeat for all columns.
- Step 5: Add all of the numbers in step 4 together.
- Step 6: Subtract the number you found in step 2 from the number you found in step 5.
Step 5-Step 2=?.
- Step 6: Take the square root of the number you found in step 6.
That’s how to find a standard deviation binomial distribution!
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