null value


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null value

A value in a field or variable that indicates nothing was ever derived and stored in it. For example, in a decimal-based amount field, a null value might be all binary 0s (null characters), but not a decimal 0. The decimal 0 would imply no dollars and cents, which could in fact be a valid derived value. See null and binary.
References in periodicals archive ?
(a) Sex-specific estimates did not meet criteria for heterogeneity (i.e., 80% credible intervals for all phthalate x sex product terms included the null value).
In histogram, the black lines represent the continuous segments and the gray parts denote the null value segments.
There is no reference to old value of the attributes, so the ID_row and IDcolumn also contain null value (example for TAB1) (see also fig.
There are a number of subqueries in SQL that may refine results to some extent, but such cannot eradicate the indeterminacy of the null value responsible for the contamination.
Given Will's claims, it may surprise some readers when I say that there are some published interpretations of confidence intervals (e.g., Guyatt et al., 1995) which lead to estimations of larger (not smaller) sample sizes than for the null hypothesis testing procedure (when zero is the chosen null value).
According to the data object characteristic, however, many null values may appear.
You may also have a case for a null value if you are working in a database and none of its values has a record.
If a row is inserted but no value is included for a column that allows null values, the database engine supplies the value NULL (unless a DEFAULT definition or object exists).
The null value function (NVL), which returns either the input value or an alternate value in the case where the input has a null value, may be used when a null value is unacceptable.
The expected null value was obtained by a Monte Carlo simulation in which the computer generated 1,000 bogus experiments of 48 sessions each, utilizing the same software used in the actual experiment and sampling from a population of key game designations (1-4) consisting of the 139 real targets.
In the case in which we use a simple null hypothesis with a composite alternative, and variation in the parameter values can be on both sides of the null value, then we have a two-sided test.
In the first case, the conditional compilation includes code to check whether an already linked node is being used, because it contains a non NULL value, or whether an unlinked node is being decoupled from the container, when the link field is already NULL.