Variance and standard deviation

 variance and standard deviation


In  statistics we come across some words which are used in so many situations and one of them are variance and standard deviation...


Variance 

The variance can be defined as the average of squared differences from mean value.In rough terms it is measure of how far set of data(numbers) are spread out from their mean (average) value.Variance never be negative.By variance we can draw some useful insights for given data.For comparison purpose variance can be useful in many cases.variance is very useful in lot of statistical measures,test,analysis and many more...






Standard deviation


Standard deviation measures how spread out the values in a data set are around the mean. More precisely, it is a measure of the average distance between the values of the data in the set and the mean. If the data values are all similar, then the standard deviation will be low (closer to zero). If the data values are highly variable, then the standard variation is high (further from zero).Standard deviation is mostly used for comparison between two data sets and in many more situations.


We can state some relation between variance and standard deviation as "standard deviation is square root of the variance" 


Thanks for reading...


Content created by - Chandrashekhar Awate and Priyanka Pawar

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