Panic attack symptoms are a common reaction. Other anxiety disorders include: agoraphobia, separation anxiety disorder and substance/medication-induced anxiety disorder involving intoxication or withdrawal or medication treatment.
Statistics and Probability Dictionary. Select a term from the dropdown text box. The online statistics glossary will display a definition, plus links to other related web pages. Select term: Variance. The variance is a numerical value used to indicate how widely individuals in a group vary. If individual observations vary greatly from the group mean, the variance is big; and vice versa. It is important to distinguish between the variance of a population and the variance of a sample.
Both standard deviation and variance are derived from the mean of a given data set. Whereas the mean is simply the average of all data points, the variance measures the average degree to which each point differs from the mean.The greater the variance, the larger the overall data range.For the variance, first calculate the difference between each point and the mean.hereas the mean is simply the average of all data points, the variance measures the average degree to which each point differs from the mean. The greater the variance, the larger the overall data range. For the variance, first calculate the difference between each point and the mean.