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.
In early spring or late winter people often encounter these large black ants in homes. These big ants are different than the more common small, brown nuisance ants that plague kitchens. The big ants are called carpenter ants (Camponotus spp.) and unlike their smaller cousins, nest above ground in cavities. Nest building and cavity expansion by these large, powerful ants can cause damage if nests occur in our homes. Most of the ants you find in homes are small, less than 1/4, and brown. There are several species of small brown ants that can nest in our home's walls or nearby soil and enter homes in search of food and water (see House Ants for identification and control). Nuisance ants are just that, a nuisance.