countably additive


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countably additive

[′kau̇nt·ə·blē ′ad·əd·iv]
(mathematics)
Given a measure m, and a sequence of pairwise disjoint measurable sets, the property that the measure of the union is equal to the sum of the measures of the sets.
References in periodicals archive ?
If A is a [sigma]-algebra of subsets of a set Y, [mu]: A [right arrow] E a countably additive vector measure and p [member of] P, we denote the p-semi-variation of [mu] by [[bar.
Then it has a unique extension to a countably additive Borel measure [mu]: B(X) [right arrow] E which is inner regular by closed sets and outer regular by open sets.
Let [mu] be a countably additive, regular, vector valued, Borel measure on R taking values in [B *.
n] is a countably additive, regular complex measure with compact support contained in K(see the proof of Singer's theorem in (2)).