Standard deviation: binomial distribution

binomial distribution, standard deviation 9 Comments

Most textbooks in elementary statistics will ask you to finding the standard deviation in the binomial probability distibution chapter. This can be a challenge, because the variance and standard deviation formulas are daunting when you first look at them. This how to will tell you how to find a standard deviation for a binomial distribution in just a few steps.

Step 3:  Make a probability distribution chart.

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-Step2=?.
  • Step 6: Take the square root of the number you found in step 6.
    √Step 6=?

That’s it!

Related posts:

  1. How to Calculate Mean and Standard Deviation for a Binomial Distribution on the TI-89
  2. How to Get The Mean and Standard Deviation For a Binomial Probability Distribution With a TI 83 Calculator
  3. How to Find a Sample Size Given a Confidence Interval and Width (Known Standard Deviation)
  4. How to find the sample variance and standard deviation in statistics
  5. The Fast Way to Find the Standard Deviation on the TI-89 Calculator
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9 Responses to “Standard deviation: binomial distribution”

  1. Lisa Barcomb said:

    Sep 20, 09 at 5:03 am

    With this section its okay until you get down to the 4th step and then I am lost although this article did help me figure out how to finish the problem. So I am glad that they do have this information in here for us to look at so we have something to fall back on.

  2. Jennifer Thomas said:

    Sep 20, 09 at 11:36 am

    It would be helfpul if you provived the results next to each step so we can work the problem as we follow each step and make sure we are calculating correctly.

  3. Rebecca Gamble said:

    Sep 22, 09 at 11:12 pm

    I wish I would have read this information before I did the long walk to ace for help! I chart is a lot of help but I agree the steps are a little confusing, just read over them two times and it will make sense.

  4. Ashanti Jones said:

    Sep 23, 09 at 5:04 pm

    This was very helpful. I was confused on the probablility distribution chart

  5. Donna Allen said:

    Sep 26, 09 at 5:42 am

    Your explanation here is much simpler and easier to follow than the one given in the book. I agree, it’s great to have this blog to fall back on.

  6. Catherine Flanagan said:

    Oct 04, 09 at 4:39 pm

    This blog did help me to understand standard deviation better, but it would be better if the problem was written out with each step. I think this would help all us visual learners!

  7. Lisa Barcomb said:

    Oct 11, 09 at 8:19 pm

    This blog really helped me with the probability chart because I was really confused for the longest time as I am sure you are well aware of. I really like looking on this because I feel like I get a better understanding.

  8. angie widdows said:

    Nov 03, 09 at 6:13 pm

    This example is very helpful because it has the links to other problems that we have already covered. We learn things in previous sections but it is always nice to be able to go back for a refresher.

  9. Vanessa DuBarry said:

    Nov 15, 09 at 7:21 pm

    This example was very helpful and It helped me with ch8 hw.

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