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| − | normal | + | <div style="font-size:30px">'''NORMALDISTRIBUTED(x,m,sd)'''</div><br/> |
| | + | *<math>x</math> is the value for which distribution is evaluated. |
| | + | *<math>m </math> is the mean. |
| | + | *<math>sd</math> is the standard deviation. |
| | + | |
| | + | ==Description== |
| | + | *This function gives the value of the normal probability distribution. |
| | + | *It is the continuous probability distribution. |
| | + | *The normal distributions are a very important class of statistical distributions. |
| | + | *All normal distributions are symmetric and have bell-shaped density curves with a single peak. |
| | + | *The term bell curve is used to describe the mathematical concept called normal distribution. |
| | + | *It is also called as Gaussian distribution. |
| | + | *The Normal Distribution has: mean = median = mode |
| | + | *i.e., This distribution is symmetry about the center. |
| | + | *Half of values less than the mean and half of values greater than the mean. |
| | + | *In a normal distribution the probability values are satisfying the following conditions: |
| | + | 1. The total area under the curve is equal to 1 (100%) |
| | + | 2. About 68% of the area under the curve falls within 1 standard deviation. |
| | + | 3. About 95% of the area under the curve falls within 2 standard deviations. |
| | + | 4. About 99.7% of the area under the curve falls within 3 standard deviations. |
| | + | *In a normal distribution the mean =0 and standard deviation =1,then the distribution is called the standard normal distribution or the unit normal distribution, and a random variable with that distribution is a standard normal deviate. |
| | + | *It is the only absolutely continuous distribution. |
| | + | *A normal distribution is calculated by : |
| | + | <math>f(x,\mu,\sigma)=\frac {1}{\sigma\sqrt{2\pi}} e^{\frac{-(x-\mu)^2}{2\sigma^2}}</math> |
| | + | where <math>\mu</math> is the mean and <math>\sigma</math> is the standard deviaton of the distribution. |
| | + | |
| | + | ==Examples== |
| | + | #NORMALDISTRIBUTED(22,25,2.5) = -16.307435699813773,69.98317771544811,13.493570858283977,46.350299353375874 etc |
| | + | #=NORMALDISTRIBUTED(30,36,20.9) = -39.85074927994863,24.24627001288364,23.575289380647483,-20.639707171803707,-8.8266089980268 etc. |
| | + | |
| | + | ==See Also== |
| | + | *[[Manuals/calci/NORMDIST | NORMDIST ]] |
| | + | *[[Manuals/calci/NORMSDIST | NORMSDIST ]] |
| | + | *[[Manuals/calci/NORMINV | NORMINV ]] |
| | + | |
| | + | ==References== |
| | + | *[http://stattrek.com/probability-distributions/normal.aspx Normal Distribution] |