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Given a partial order R$R_{\leq}$ over a set D$D$, the set of upper bounds under R$R$ of a subset S$S$ of D$D$ is commonly defined as { yD | ∀ xS, x R y }$\{ y \in D | \ \forall x\in S, x R y \}$.

(The set of lower bounds of S$S$ may be defined as the set of upper bounds of S$S$ under the converse relation R-1$R^{-1}$)

Is there a common name for the generalization of this notion where R$R$ is not a partial order, and is possibly a heterogenous relation between domain D$D$ and codomain D'$D'$ (hence the y$y$ would be elements of the codomain)? This would be a subset of the image of S$S$ under R$R$ (and conversely, the dual notion would be a subset of the preimage).

Given a partial order R over a set D, the set of upper bounds under R of a subset S of D is commonly defined as { yD | ∀ xS, x R y }.

(The set of lower bounds of S may be defined as the set of upper bounds of S under the converse relation R-1)

Is there a common name for the generalization of this notion where R is not a partial order, and is possibly a heterogenous relation between domain D and codomain D' (hence the y would be elements of the codomain)? This would be a subset of the image of S under R (and conversely, the dual notion would be a subset of the preimage).

Given a partial order $R_{\leq}$ over a set $D$, the set of upper bounds under $R$ of a subset $S$ of $D$ is commonly defined as $\{ y \in D | \ \forall x\in S, x R y \}$.

(The set of lower bounds of $S$ may be defined as the set of upper bounds of $S$ under the converse relation $R^{-1}$)

Is there a common name for the generalization of this notion where $R$ is not a partial order, and is possibly a heterogenous relation between domain $D$ and codomain $D'$ (hence the $y$ would be elements of the codomain)? This would be a subset of the image of $S$ under $R$ (and conversely, the dual notion would be a subset of the preimage).

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François G. Dorais
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Name for "lower/upper bounds" of arbitrary relations?

Given a partial order R over a set D, the set of upper bounds under R of a subset S of D is commonly defined as { yD | ∀ xS, x R y }.

(The set of lower bounds of S may be defined as the set of upper bounds of S under the converse relation R-1)

Is there a common name for the generalization of this notion where R is not a partial order, and is possibly a heterogenous relation between domain D and codomain D' (hence the y would be elements of the codomain)? This would be a subset of the image of S under R (and conversely, the dual notion would be a subset of the preimage).