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.
Ants are eusocial insects of the family Formicidae /fÉrËmÉªsÉ¨diË/ and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants.nts vary in colour; most ants are red or black, but a few species are green and some tropical species have a metallic lustre. More than 12,000 species are currently known (with upper estimates of the potential existence of about 22,000) (see the article List of ant genera), with the greatest diversity in the tropics.