Standard deviation from ungrouped data. The standard deviation is a summary measure of the differences of each observation from the mean. If the differences themselves were added up, the positive would exactly balance the negative and so their sum would be zero. Consequently the squares of the differences are added.
A pissant, also seen as piss ant or piss-ant, refers to a specific type of ant. The word is also used as a pejorative noun or adjective, indicating insignificance.he original pissant is any of a certain group of large ant species, commonly called wood ants, that make mounded nests in forests throughout most of Europe.
Little black ants are small and dark-brown, black or jet black in color and are a native species found throughout the United States. The workers are as small as 1.5 mm in length, and queens can measure up to 4 mm. Their antennae consist of 12 segments and end in a three-segmented club. Their pedicel, or the ant waist, is two-segmented. Little black ants have no spines, and their thorax is unevenly rounded.