Solved

# Data statistical significance with confidence factor

Posted on 2014-01-17
148 Views
Hi,

With a supplied set of data say...

0.2 1.4 3.2 2.2 6.4 3.1 9.2 5.3 3.3 2.9 etc

How can I calculate the statistical significance of this data and show the confidence level in %, and also if I wish it to be defined i.e. I want 95% confidence, how do I get it to inform me of the number of samples required to achieve this level?

Thank you
0
Question by:DemonForce
• 2

LVL 24

Expert Comment

For confidence levels you require more information than simply a list of numbers.

0

LVL 42

Assisted Solution

Rob Jurd, EE MVE earned 250 total points
0

Author Comment

Ok, if I want 95% and I keep entering in numbers between 0.0 and 999.9, using mathematical techniques I need to know as I continue to type numbers in what the current confidence factor is, and how many more samples I need to keep inputting to get this to 95%
0

LVL 24

Accepted Solution

Steve earned 250 total points
But confident of what?
With these numbers between 0 and 1000 you want to 95% confident they are ... ?

You can determine the average of the numbers. "xBar"
You can determine the standard deviation of the numbers. "sigma"
you can then multiply the standard deviation by 1.96. "1.96sigma"
Then xBar - 1.96sigma = lower confidence interval at 95%
Then xBar + 1.96sigma = upper confidence interval at 95%
Therefore you could say that with the data there is a 95% chance numbers will fall between the upper and lower confidence levels (in a continuous process the likelihood is 95% that the next number will be between these numbers.

But to get to a practical confidence factor you would need to have a target for the upper and lower... such as "I want to be 95% confident that the numbers are between 250 and 750".

ATB
Steve.
0

## Featured Post

### Suggested Solutions

How to quickly and accurately populate Word documents with Excel data, charts and images (including Automated Bookmark generation) David Miller (dlmille) Synopsis In this article you’ll learn how to use ExcelToWord! to copy data,charts, shapes …
This code takes an Excel list of URL’s and adds a header titled “URL List”. It then searches through all URL’s in column “A”, looking for duplicates. When a duplicate is found, it is moved to the top of the list. The duplicate URL’s are then highlig…
This Micro Tutorial demonstrate the bugs in Microsoft Excel for Mac with Pivot Charts.
Excel styles will make formatting consistent and let you apply and change formatting faster. In this tutorial, you'll learn how to use Excel's built-in styles, how to modify styles, and how to create your own. You'll also learn how to use your custo…