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In statistics, specifically, a null result occurs when there are non-significant differences between experimental and control conditions. While some differences may in fact be observed, they are below the threshold set prior to testing. The cutoff for these significance values varies, but is often .05. This is considered evidence for the null hypothesis.
In computer science and Information technology, null (e.g. NULL or nil) is the name for a value outside the normal domain of processing.
nil) as a pointer value not referring to any valid memory location.
if (p != NULL) {free(p); p=NULL;} /* Safe release of allocated memory */
NULL is a special value in SQL that represents an unknown, missing, inapplicable, or undefined value.
delete from my_users where password is null; /* Remove users who have no password */
nil in Lisp and Scheme represents the empty list ().
(cons 4 nil) ; Construct a list from the list (4) and the null list, resulting in the list (4).
Nulls are treated differently depending on the language or program.
nil is both the empty list and the boolean false value, whereas in Scheme it is only the empty list. The values #t and #f are used in Scheme to denote true and false.
NULL using normal comparison operators, it can only be tested (IS NULL and IS NOT NULL).
NULL pointer is undefined, it can often result in a fatal execution error, and the results are always undesirable.
In physics, the results of the Michelson-Morley experiment, which did not detect the aether, was of this type. This experiment's famous failed detection, commonly referred to as the null result, caused the aether theory to be abandoned. Albert EinsteinAlbert Einstein ( March 14 1879 April 18 1955) was a theoretical physicist who is widely regarded as the greatest scientist of the 20th century. He proposed the theory of relativity and also made major contributions to the development of quantum mechanics's theory of relativityAlbert Einstein's theory of relativity is a set of two theories in physics: special relativity and general relativity. The core idea of both theories is that two observers who move relative to each other will often measure different time and space interva followed close upon this null result. This theory does not make use of the aether concept.
In logic, null result is an invalid value of a proposition. It is one of the possibilities in a three-valued logicIn ordinary language, logic is the reasoning used to reach a conclusion from a set of assumptions. More formally, logic is the study of inference—the process whereby new assertions are produced from already established ones. As such, of particular concern (true, false, or null result).