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D.W.
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If you are promised that $I$ is an independence system, thisThis looks equivalent to finding all maximal elementszeroes of a monotone function, given ability to make oracle queries to the function. Let $f:\{0,1\}^n \to \{0,1\}$ be a monotone Boolean function, and call $x$ a maximal zero if $f(x)=0$ and $f(y)=1$ for all $y\ge x$ (i.e., $y_i \ge x_i$ for all $i$).

This problem has been studied extensively. I believe there are no known polynomial time algorithms. See https://cstheory.stackexchange.com/q/14772/5038, Maximal Elements in a Lower Set, https://cstheory.stackexchange.com/q/18047/5038, How to enumerate minimal covers of a set, and https://cstheory.stackexchange.com/q/14772/5038. I think the concepts of learning DNF representations for monotone boolean functions and monotone dualization will be relevant. I confess I don't fully understand the literature and don't know if there are any algorithms that are good-enough-in-practice.

The relationship: Suppose there are $n$ elements in the universe, so that each set $A \in I$ satisfies $A \subseteq \{1,2,\dots,n\}$$\Omega=\{1,2,\dots,n\}$. We can identify the set $A$ with its characteristic vector, which is an element of $\{0,1\}^n$. Now an independence system $I$ determines a function $f$ given by $f(A)=0$ if $A \in I$ and $A$ is independent in $I$, otherwise $f(A)=1$. You have oracle access to $f$, and want to find all maximal sets $A$ such that $f(A)=0$.

If you are promised that $I$ is an independence system, this looks equivalent to finding all maximal elements of a monotone function, given ability to make oracle queries to the function. Let $f:\{0,1\}^n \to \{0,1\}$ be a monotone Boolean function, and call $x$ maximal if $f(x)=0$ and $f(y)=1$ for all $y\ge x$.

This problem has been studied extensively. I believe there are no known polynomial time algorithms. See https://cstheory.stackexchange.com/q/14772/5038, Maximal Elements in a Lower Set, https://cstheory.stackexchange.com/q/18047/5038, How to enumerate minimal covers of a set, and https://cstheory.stackexchange.com/q/14772/5038. I think the concepts of learning DNF representations for monotone boolean functions and monotone dualization will be relevant. I confess I don't fully understand the literature and don't know if there are any algorithms that are good-enough-in-practice.

The relationship: Suppose there are $n$ elements in the universe, so that each set $A \in I$ satisfies $A \subseteq \{1,2,\dots,n\}$. We can identify the set $A$ with its characteristic vector, which is an element of $\{0,1\}^n$. Now an independence system $I$ determines a function $f$ given by $f(A)=0$ if $A \in I$ and $A$ is independent in $I$, otherwise $f(A)=1$.

This looks equivalent to finding all maximal zeroes of a monotone function, given ability to make oracle queries to the function. Let $f:\{0,1\}^n \to \{0,1\}$ be a monotone Boolean function, and call $x$ a maximal zero if $f(x)=0$ and $f(y)=1$ for all $y\ge x$ (i.e., $y_i \ge x_i$ for all $i$).

This problem has been studied extensively. I believe there are no known polynomial time algorithms. See https://cstheory.stackexchange.com/q/14772/5038, Maximal Elements in a Lower Set, https://cstheory.stackexchange.com/q/18047/5038, How to enumerate minimal covers of a set, and https://cstheory.stackexchange.com/q/14772/5038. I think the concepts of learning DNF representations for monotone boolean functions and monotone dualization will be relevant. I confess I don't fully understand the literature and don't know if there are any algorithms that are good-enough-in-practice.

The relationship: Suppose $\Omega=\{1,2,\dots,n\}$. We can identify the set $A$ with its characteristic vector, which is an element of $\{0,1\}^n$. Now an independence system $I$ determines a function $f$ given by $f(A)=0$ if $A \in I$, otherwise $f(A)=1$. You have oracle access to $f$, and want to find all maximal sets $A$ such that $f(A)=0$.

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D.W.
  • 165.6k
  • 21
  • 230
  • 490

If you are promised that $I$ is an independence system, this looks equivalent to finding all maximal elements of a monotone function, given ability to make oracle queries to the function. Let $f:\{0,1\}^n \to \{0,1\}$ be a monotone Boolean function, and call $x$ maximal if $f(x)=0$ and $f(y)=1$ for all $y\ge x$.

This problem has been studied extensively. I believe there are no known polynomial time algorithms. See https://cstheory.stackexchange.com/q/14772/5038, Maximal Elements in a Lower Set, https://cstheory.stackexchange.com/q/18047/5038, How to enumerate minimal covers of a set, and https://cstheory.stackexchange.com/q/14772/5038. I think the concepts of learning DNF representations for monotone boolean functions and monotone dualization will be relevant. I confess I don't fully understand the literature and don't know if there are any algorithms that are good-enough-in-practice.

The relationship: Suppose there are $n$ elements in the universe, so that each set $A \in I$ satisfies $A \subseteq \{1,2,\dots,n\}$. We can identify the set $A$ with its characteristic vector, which is an element of $\{0,1\}^n$. Now an independence system $I$ determines a function $f$ given by $f(A)=0$ if $A \in I$ and $A$ is independent in $I$, otherwise $f(A)=1$.