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Easy instance of set cover

I am trying to prove that a natural greedy algorithm solves the following instance of the set cover problem: for a set of elements $e\in U$ with a set of weights $w_e$, we define the cost of a subset ...
Tom Solberg's user avatar
  • 4,049
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ILPs with square constraint matrix

Given the Integer Linear Programming ($\text{ILP}$) problem \begin{array}{ll} \text{minimize} & c^T x \\ \text{subject to}& \mathbf{A}^T x \ge b \\ \text{where}&c,x,b\in\mathbb{N}_0^n,\\ &...
Manfred Weis's user avatar
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Alternatives to McCormick Envelope

I have an optimization problem for which I have the optimal solution obtained by the ILP. However, when I introduced the McCormick Envelope to replace the product of a bi-linear term in its LP ...
LyLa's user avatar
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Subtour-gluing constraints for ILP formulation of TSPs

If one doesn't want to introduce additional variables to the ILP of a TSP instance, one has to add exponentially many so-called subtour-elimination constraints; in practical calculations subtour-...
Manfred Weis's user avatar
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1 vote
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37 views

Fast certficate of negativity for objective value of mixed-integer linear program

Let $c \in \mathbb R^n$, $A \in \mathbb R^{m \times n}$, $b \in \mathbb R^m$, and $I \subseteq \{1,2,\ldots,n\}$. Consider the Mixed integer linear program (MILP) $$ \begin{split} f^* = &\max \; ...
dohmatob's user avatar
  • 6,853
1 vote
1 answer
330 views

How good is the LP relaxation?

Consider the optimization problem \begin{align} \max_{x\in\mathbb{R}^n}~c^Tx~, \text{ s.t. } Ax=b,~x_i\in\{0,1\}~\forall i \end{align}where $c,b\in\mathbb{R}_{+}^n$ and $A\in\mathbb{R}_{+}^{n\times n}$...
dineshdileep's user avatar
  • 1,421
2 votes
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120 views

integrality of a linear program -- binary equality constaints

Consider the following linear program: $\left\{ \begin{array}{l} \underset{x}{max} \;\;c^Tx\\ [I, \;B]x = \mathbf{1}\\ x\geq 0 \end{array} \right.$ where $c$ is a vector ...
Ali's user avatar
  • 127
1 vote
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75 views

Are there any known bounds on the value of solutions of linear integer programming?

Given a linear objective function and a system of linear constraints; are there any known bounds on the values of (positive) integral solutions in terms of the coefficient matrix of the constraints? ...
GLG's user avatar
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