Binary representations of underdetermined data and superimposed codes

For underdetermined data, binary representations are defined, making it possible to reconstruct the initial data entirely (not only their specifications) and being fairly compact. To solve the problem of their design, some special matrices called selective ones are introduced and studied. They generalize the disjunct (cover-free) matrices widely applied in Computer Science. Some characteristics of selective matrices and estimates of data representation length via some data parameters are investigated. Problems related to the complexity of representations design are considered too.