Soundness of mind

What is the difference between standard deviation and variance?

The standard deviation and variance both measure the spread of a data set, and are closely related. The variance is the average of the squared differences from the mean, while the standard deviation is the square root of the variance. The standard deviation is more widely used because it is expressed in the same units as the original data, while the variance is expressed in squared units. Generally, the standard deviation is more useful for making comparisons between different data sets.

Should I use variance or standard deviation?

The choice of whether to use variance or standard deviation depends on the assumptions you are making about the data you are analyzing. Generally, if you are making assumptions about the data being normally distributed, then it is usually better to use standard deviation. However, if you are making assumptions about the data being non-normally distributed, then it may be better to use variance. It is important to consider the context of the data when making a decision about which measure to use.