That's because a lot of VoIP services out there go by their product names and don't make a lot of noise about it. (That's not a big deal and they're not trying to hide it. For example, if you've heard of Skype, you've heard of one of the best-known Web-based VoIP services in use.
The Range Rule. The range rule tells us that the standard deviation of a sample is approximately equal to one fourth of the range of the data. In other words s = (Maximum â Minimum)/4.This is a very straightforward formula to use, and should only be used as a very rough estimate of the standard deviation.he Range Rule. The range rule tells us that the standard deviation of a sample is approximately equal to one fourth of the range of the data. In other words s = (Maximum â Minimum)/4.
Standard Deviation Calculator. Here are the step-by-step calculations to work out the Standard Deviation (see below for formulas). Enter your numbers below, the answer is calculated live: When your data is the whole population the formula is: (The Population Standard Deviation ).