In cases of immune system over activity, the body attacks and damages its own tissues (autoimmune diseases). Immune deficiency diseases decrease the body's ability to fight invaders, causing vulnerability to infections.
Standard deviation is a measure of spread (like Range, Variance, or IQR) so it tells you how wide or concentrated your data is. You can interpret it as how far away the typical/average observation is from the mean.
Sample Standard Deviation. A standard deviation of a sample estimates the standard deviation of a population based on a random sample. The sample standard deviation, unlike the population standard deviation, is a statistic that measures the dispersion of the data around the sample mean.tandard deviation refers to the amount of dispersion in a given data set. Researchers calculate the standard deviation of a data set by taking the square root of the variance, and the numerical result is indicated by the letter S. They use the term âvarianceâ to describe the extent of the data spread.