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Solver Max @solvermax.com · Jul 14

Article: Jury simulation using SimPy
We design and build a SimPy model of jury summoning to reduce the number of people required.
This model highlights a key lesson for simulation modelling in general: details matter, sometimes a lot.
#orms #Python
www.solvermax.com/blog/jury-si...

Solver Max @solvermax.com · Jun 9

Efficient jury empanelling: Respecting people's time

We describe a simulation model of the jury selection process. The goal is to explore how the needs of the justice system can be met while respecting the time of people who report for jury service.

#orms #Python
www.solvermax.com/blog/efficie...

Solver Max @solvermax.com · May 3

The muffin problem: A slice of recreational maths
We solve 'The Muffin Problem': divide muffins equally between students, maximizing the smallest piece.
Our MILP model is solved in parallel with symmetry-breaking constraints and objective bounds.
#orms #Python
www.solvermax.com/blog/the-muf...

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Solver Max @solvermax.com · Apr 2

Pivot irrigators in a 100 acre field
We formulate a non-linear, non-convex model for optimizing the layout of centre-pivot irrigators in a field.
Several solvers fail to find good solutions. Can the MINLP-BB solver via NEOS find an optimal solution?
#orms #Python
www.solvermax.com/blog/pivot-i...

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Solver Max @solvermax.com · Mar 7

Locational marginal pricing of potatoes

We apply Locational Marginal Pricing (LMP) to the supply of potatoes. The article describes the model, calculation of LMPs, and scenarios for how the suppliers and contractors may respond to the price signals.
#orms #pyomo
www.solvermax.com/blog/locatio...

Washed potatoes, ready for chopping into French Fries.

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Reposted by Solver Max

Geoffrey De Smet @geoffreydesmet.bsky.social · Feb 10

How I built an AI company to save my open source project

On this day, 3 years ago, my world fell apart. It was a Thursday. I just finished my second meeting that morning, looked at my inbox and realized it was over. My life’s work was over.

Read more:
timefold.ai/blog/how-i-b...

How I built an AI company to save my open source project

The story of Timefold: how we turned a doomed open source project into a fast-growing PlanningAI company.

timefold.ai

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Solver Max @solvermax.com · Feb 10

That's a great story.

I've been intending to add Timefold to our list of optimization modelling resources. Your post prompted me to do so: www.solvermax.com/resources/li...

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Solver Max @solvermax.com · Feb 7

Permission granted: A role mining model

We implement a recently published role mining model using both constraint programming and mixed integer linear programming, then compare their relative performance while solving several examples.

www.solvermax.com/blog/permiss...

#orms #pyomo #ortools

Solver Max @solvermax.com · Feb 6

New item in our list of #orms resources:

Collection of videos from Associate Professor Alberto Del Pia, University of Wisconsin-Madison.
There are around 100 videos, collated into playlists relating to specific optimization papers taught at the university.
www.solvermax.com/resources/li...

Illustration of cutting plane in linear programming

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Solver Max @solvermax.com · Jan 7

Optimal rational approximation using SciPy

In this article we solve a non-linear curve fitting problem using the SciPy library. We illustrate SciPy's curve_fit and minimize functions and look at some good practices.
#python #scipy #orms
www.solvermax.com/blog/optimal...
@johndcook.bsky.social

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Solver Max @solvermax.com · Dec 23

We've added the "Book Proofs" blog by Laurent Lessard @laurentlessard.bsky.social to our list of #orms resources:
www.solvermax.com/resources/li...

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Solver Max @solvermax.com · Dec 23

Absolutely. A MILP is a very impractical way of compiling a crossword. The goal was to see if it would work, which it mostly does. The contrast with 1989 is also remarkable.

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Solver Max @solvermax.com · Dec 22

Just for fun, I created a Mixed Integer Linear Program for compiling crosswords www.solvermax.com/blog/crosswo...

Solver Max - Crossword MILP - Model 1

We use a mixed integer linear program to compile crossword grids

www.solvermax.com

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Solver Max @solvermax.com · Dec 20

We've added the "Feasible" blog, written by Borja Menéndez, to our list of #orms resources:
www.solvermax.com/resources/li...

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Solver Max @solvermax.com · Dec 16

We've added the "Princeton Consultants' Optimization" blog to our list of #orms resources:
www.solvermax.com/resources/li...

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Solver Max @solvermax.com · Dec 14

We've added the Cornell "Computational optimization open textbook" to our list of #orms resources: www.solvermax.com/resources/li...

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Solver Max @solvermax.com · Dec 8

We've added the blog by @richardoberdieck.bsky.social to our list of #orms resources: www.solvermax.com/resources/li...

Please comment to suggest other #orms resources, like blogs, courses, online textbooks, etc. that we can add.

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Solver Max @solvermax.com · Dec 4

While solving MIPs using AI seems like a pointless exercise, I did use an AI to find the paper you're referring to. So, AIs are good for some things.

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Solver Max @solvermax.com · Dec 4

I've found ChatGPT & Claude somewhat better at programming, but much the same as Copilot for optimization model code.
Perhaps an AI trained specifically on models would be better. @gurobioptimization.bsky.social have started looking at AI, so we'll see what they find www.gurobi.com/resources/br...

Bridging the Optimization Skills Gap With Generative AI - Gurobi Optimization

How GenAI can make optimization tools more accessible and effective

www.gurobi.com

Solver Max @solvermax.com · Dec 4

The process was a roller coaster. I was impressed by the AI's astuteness but frustrated by its strange mistakes.
I'm increasingly using AI for coding tasks - either straightforward yet time-consuming things, or to get syntax right for unfamiliar things. It mostly performs well in these situations.

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Solver Max @solvermax.com · Dec 4

Blog: Can AI code an entire optimization model?
We report our experience of using Copilot to write a non-trivial optimization model for us. We focus on what went well and what didn't go well, plus some general lessons from the process.
www.solvermax.com/blog/can-ai-...
#orms #copilot #llm #ai

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Solver Max @solvermax.com · Nov 20

Though I object to paying 39,95 € just to look at an article. But that's a different issue.

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Solver Max @solvermax.com · Nov 20

Perhaps "often" is a bit harsh. But I'd have better evidence if the code is published too.
I hope you're right about the culture changing.

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Solver Max @solvermax.com · Nov 20

I suppose a formulation is better than nothing. But published formulations are often wrong.
For example in www.solvermax.com/blog/green-m... we get a better optimal solution.
In another case, our solution was worse than in the paper. In discussion with the author it emerged that the paper is wrong.🤷

Solver Max - Green manufacturing via cutting patterns

Solver model of a one dimensional cutting problem in Excel

www.solvermax.com

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Solver Max @solvermax.com · Nov 20

The Gomes, et al paper we summarize lists many reasons why academics may not publish code and data - along with mitigations that should encourage publication.
I approach this issue from a selfish perspective. When looking to the literature for help with a problem, a formulation is seldom sufficient.

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