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Whats the name of the algorithm/concept used here? I used simulated annealing, old fashioned algorithm for a college timetable prototype and I'm wondering how t

Whats the name of the algorithm/concept used here? I used simulated annealing, old fashioned algorithm for a college timetable prototype and I'm wondering how this company is using an AI model.

PeterStuer 2y ago
It is a constrained solver. You can argue about what is or is not AI. It varies over time, traditionally driven by in which part of the AI boom/ bust cycle we were, and lately also by which regulations would apply. My background is in AI but I would have been hesitant calling the rule based systems I wrote to automate financial descisions AI at the time. In this case, Geoffrey also seemed hesitant in the past to refer to his system as AI (see https://www.optaplanner.org/blog/2017/09/07/DoesAIIncludeConstraintSolvers.html https://www.optaplanner.org/blog/2017/09/07/DoesAIIncludeCon... ), but somtimes you just have to ride the wave that brings in the funding.
- wisty 2y ago
  Rule based systems can fall more into the side of AI than ML.
  - PeterStuer 2y ago
    Objectively I agree. Commercially it's a different story. I also think AI ousting ML historically was uncalled for, and those that did should bow their heads in shame.
- throwaway346434 2y ago
  I have prototyped using timefold in a work project for hospital bed allocation. Using the shortcut of "It's AI, but it won't hallucinate because it follows all of your policy and rules" has been a great way to onboard both non technical folks and operators warming up to the idea.
- aitchnyu 2y ago
  <Looks up Geoffrey> I used Drools Planner in 2012, which is a predecessor of Timefold. There was no talk of distilled "models" back then, but this article mentions models as if its a secret sauce.
viccis 2y ago
I did something like this for a project in a class almost two decades ago. The project was to make a system that would take a bunch of students' schedules and produce a list of teams that optimized for shared free time. I started with simulated annealing and then ended up with a genetic algorithm.
ge0ffrey 2y ago
We support Simulated Annealing too, as well as Tabu Search and many others. By default Timefold Solver uses Late Acceptance, which behaves like Simulated Annealing but isn't parameter tuning fickle like SA. Do note that the base algorithm (such as SA, TS or LA) is less than 5% of the work to get great results. We do a lot of additional things on top of that (incremental score calculation, smart neighborhood selection, multi threaded solving and many more).
- aitchnyu 2y ago
  Hey Geoffrey, I missed that you were behind this! You did help me choose Drools Planner with simulated annealing in 2012. Congrats on coming a long way since then! https://stackoverflow.com/questions/8712955/which-drools-product-to-use-for-timetabling https://stackoverflow.com/questions/8712955/which-drools-pro...

Whats the name of the algorithm/concept used here? I used simulated annealing, old fashioned algorithm for a college timetable prototype and I'm wondering how this company is using an AI model.

PeterStuer 2y ago

It is a constrained solver. You can argue about what is or is not AI. It varies over time, traditionally driven by in which part of the AI boom/ bust cycle we were, and lately also by which regulations would apply. My background is in AI but I would have been hesitant calling the rule based systems I wrote to automate financial descisions AI at the time. In this case, Geoffrey also seemed hesitant in the past to refer to his system as AI (see https://www.optaplanner.org/blog/2017/09/07/DoesAIIncludeConstraintSolvers.html https://www.optaplanner.org/blog/2017/09/07/DoesAIIncludeCon... ), but somtimes you just have to ride the wave that brings in the funding.

wisty 2y ago
Rule based systems can fall more into the side of AI than ML.
- PeterStuer 2y ago
  Objectively I agree. Commercially it's a different story. I also think AI ousting ML historically was uncalled for, and those that did should bow their heads in shame.
throwaway346434 2y ago
I have prototyped using timefold in a work project for hospital bed allocation. Using the shortcut of "It's AI, but it won't hallucinate because it follows all of your policy and rules" has been a great way to onboard both non technical folks and operators warming up to the idea.
aitchnyu 2y ago
<Looks up Geoffrey> I used Drools Planner in 2012, which is a predecessor of Timefold. There was no talk of distilled "models" back then, but this article mentions models as if its a secret sauce.

viccis 2y ago

I did something like this for a project in a class almost two decades ago. The project was to make a system that would take a bunch of students' schedules and produce a list of teams that optimized for shared free time. I started with simulated annealing and then ended up with a genetic algorithm.

ge0ffrey 2y ago

We support Simulated Annealing too, as well as Tabu Search and many others. By default Timefold Solver uses Late Acceptance, which behaves like Simulated Annealing but isn't parameter tuning fickle like SA. Do note that the base algorithm (such as SA, TS or LA) is less than 5% of the work to get great results. We do a lot of additional things on top of that (incremental score calculation, smart neighborhood selection, multi threaded solving and many more).

aitchnyu 2y ago
Hey Geoffrey, I missed that you were behind this! You did help me choose Drools Planner with simulated annealing in 2012. Congrats on coming a long way since then! https://stackoverflow.com/questions/8712955/which-drools-product-to-use-for-timetabling https://stackoverflow.com/questions/8712955/which-drools-pro...