abstract set representing the sample space of a random experiment. The elements in are the possible outcomes of the experiment.
: power set of , the set of all possible subsets of .
Most of subsets will be thought as events.
Collection of subsets .
The empty set .
is a -field, usually connected with the sample space .
is the Borel -field of .
is a probability measure function .
is a probability space.
is a shortcut to denote a disjoint union, for example writing means that the sets and are disjoint, while writing means that the sets and are not disjoint.
denotes an univariate random variable, while a generic collection of realization of the random variable. Where small letter, e.g denotes a scalar.
Bold and capital letter stands for a matrix, i.e. denotes a matrix of random variables each one with observations, where bold with small letter denotes a vector for . In matrix context, the index denotes a generic row, while a generic column.