Jim Luedtke
@optimizer.bsky.social
๐ค 438
๐ฅ 183
๐ 31
Professor, Stochastic and Integer Optimizer, Dad
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Jim Luedtke
Rolf van der Hulst
2 days ago
I am happy to share my latest work ``Folding Mixed-Integer Linear Programs and Reflection Symmetries'', where I formulate two new presolving techniques for handling symmetries in linear programs and mixed-integer linear programs. Check out the preprint here:
lnkd.in/efgYeVSJ
lnkd.in/eGpim7U9
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LinkedIn
This link will take you to a page thatโs not on LinkedIn
https://lnkd.in/efgYeVSJ
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Jim Luedtke
Thiago Serra
6 days ago
Thanks for all the OptiBeer
@optimizer.bsky.social
@jefflinderoth.bsky.social
and for the OptiWine
@lauraalbertphd.bsky.social
Heading back to Corn Land from Dairy Land after a day packed with very interesting research discussions
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Itโs an incredible honor to be a plenary speaker at
#ISMP2027
alongside these amazing optimizers. I look forward to seeing all my optimization friends in Amsterdam!
add a skeleton here at some point
13 days ago
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Jim Luedtke
Thiago Serra
14 days ago
There are many things about preparing and presenting slides that I keep repeating to students, so I figured that I should put them down in writing. I do think that they help a lot. (And if I am doing it, why not share it more broadly?)
thiagoserra.com/2026/03/03/m...
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My presentation philosophy
There are many things about preparing and presenting slides that I keep repeating to students, so I figured that I should put them down in writing. I do think that they help a lot. (And if I am doiโฆ
https://thiagoserra.com/2026/03/03/my-presentation-philosophy/
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Jim Luedtke
Julian Togelius
16 days ago
Saving peer review from AI slop requires getting rid of anonymous submissions and reviews
togelius.blogspot.com/2026/03/savi...
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Saving peer review from AI slop requires getting rid of anonymous submissions and reviews
The scientific ecosystem is struggling to deal with AI-written papers, and this is a great opportunity to revisit how we publish, where, and...
https://togelius.blogspot.com/2026/03/saving-peer-review-from-ai-slop.html
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Jim Luedtke
Sophie Huiberts
17 days ago
Come see me speak about the new era of simplex method theory. Wednesday!
add a skeleton here at some point
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Jim Luedtke
Thiago Serra
19 days ago
Mark your calendars and start optimizing your resources and schedules: the 2027 International Symposium on Mathematical Programming will be held from July 25 to to 30 in beautiful Amsterdam! Neil Yorke-Smith and I will organize the stream Discrete Optimization with Machine Learning.
#ismp2027
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ISMP 2027 | Home
https://ismp2027.mathopt.nl/
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Jim Luedtke
ISMP 2027 โ Amsterdam
19 days ago
๐ข
#ISMP2027
comes to Amsterdam! The 26th International Symposium on Mathematical Programming will be held July 25โ30, 2027. Join researchers from around the world to discuss advances, challenges, and opportunities in the theory and practice of mathematical optimization. ๐
ismp2027.mathopt.nl
#MOS
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The 26th International Symposium on Mathematical Programming will be held in Amsterdam, The Netherlands, from July 25th through July 30th, 2027. The event is the symposium of the Mathematical Optimization Society (MOS).
https://ismp2027.mathopt.nl
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Jim Luedtke
TCS+
22 days ago
And... we are back on ๐! The first talk of the season will be delivered by Sophie Huiberts (CNRS,
@sophie.huiberts.me
), on โฐ March 4 (10am PT, 1pm ET, 19:00 CET): "Analyzing the Simplex Method by the Book" RSVP to receive the link (one day before the talk):
forms.gle/aD621bCwswjB...
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TCS+ RSVP: Sophie Huiberts (2026/03/04)
Title: Analyzing the Simplex Method by the Book
https://forms.gle/aD621bCwswjBihxv7
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Jim Luedtke
Cathy Wu
27 days ago
Have you noticed how navigation apps include walking & waiting for public transit, but excludes parking & walking for driving? After being late a few times ๐ , we finally did. We got curious: what if these apps account for parking?
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Jim Luedtke
Alexander Helber
28 days ago
Question for
#orms
people: do you know any problem-specific cutting planes that are not too hard to explain and separate and would improve performance compared to a baseline MIP solver (e.g. SCIP, Gurobi)? Asking because its more fun for students if they implement something and it helps performance
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Jim Luedtke
Marco Lรผbbecke
about 1 month ago
our
#openaccess
book on "branch-and-price" is finally published; you can download it here
link.springer.com/book/10.1007...
#orms
@springernature.com
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Jim Luedtke
ProPublica
about 1 month ago
1/ ProPublica collected handwritten letters in mid-January from children held at the Dilley Immigration Processing Center, the same facility where 5-year-old Liam Conejo Ramos was taken. Hundreds of kids are still detained. Weโll let the childrenโs words speak for themselves. ๐งต
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Jim Luedtke
Cathy Wu
about 1 month ago
๐ฃ ๐ฃ๐ผ๐๐๐ฑ๐ผ๐ฐ ๐ผ๐ฝ๐ฒ๐ป๐ถ๐ป๐ด๐ ๐ถ๐ป ๐บ๐ ๐ด๐ฟ๐ผ๐๐ฝ! Iโm looking to hire ๐ญโ๐ฎ ๐ฝ๐ผ๐๐๐ฑ๐ผ๐ฐ๐ to work with us across the groupโs research areas, including: ๐ค Deep reinforcement learning ๐ฆ Traffic modeling & control ๐ง Neural combinatorial optimization
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Prospective Members
Faster, evidence-based decisions for sociotechnical systems
https://cathywu.github.io/prospective/
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Jim Luedtke
Katie Mack
about 2 months ago
A reminder to the news media: โconflicting accountsโ is what you say BEFORE the incontrovertible video evidence appears. After that, your job is to ask why one side is lying, not to repeat the lie and pretend no one knows the truth.
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Jim Luedtke
Don Moynihan
about 2 months ago
Alex Pretti was an ICU nurse serving veterans. He died trying to protect protestors being assaulted. A group of anonymous & masked men fired chemicals into his face, beat him, disarmed him, and shot him in broad daylight in front of witnesses. Then his government smeared him & defended his murder.
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Jim Luedtke
Senator Patty Murray
about 2 months ago
This looks like an execution. There must be an investigation. There must be accountability. Joining ICE does not give you license to murder. The President is escalating the situationโand I have no faith he will stop. The Republican Congress must join us to end this. Enough.
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Live: Man shot and killed by federal agents in Minneapolis this morning, police chief says
A video appears to shows federal agents wrestling a man to the ground then shooting him. The Department of Homeland Security said the man was armed with a gun.
https://www.startribune.com/ice-raids-minnesota/601546426
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Jim Luedtke
max nesterak
about 2 months ago
Itโs -9 degrees. Downtown Minneapolis is packed for the anti-ICE rally and the crowd keeps growing
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Jim Luedtke
Karmel S. Shehadeh
2 months ago
Happy to chair this yearโs Lifetime Achievement in Location Analysis Award committee with co-chairs Dr. Sibel Alumur Alev (University of Waterloo) and Dr. Rajan Batta (University at Buffalo). Please see the call for nominations and help spread the word!
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Jim Luedtke
nora rude (they/them ze/hir)
11 months ago
to turn off autoplaying video on the bluesky mobile app select the icon in the top left corner go to settings go to content and media make sure "autoplay videos and gifs" is toggled off
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Jim Luedtke
Karmel S. Shehadeh
2 months ago
Iโm happy to share that Iโm starting my term as President of
@informs.bsky.social
Section on Location Analysis. I look forward to continuing to serve our community, leading SOLA activities, supporting our members, and strengthening the impact of location analysis research and applications.
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Jim Luedtke
Prof Christina Pagel
3 months ago
I've written an end of year substack post about tracking Trump, where we are ending the year and some implications for Europe and for me personally...
christinapagel.substack.com/p/personal-r...
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Personal reflections on a Trumpian 2025
The implications of a year in Trump's new America and why I started tracking Trump - and why I'm not stopping.
https://christinapagel.substack.com/p/personal-reflections-on-a-trumpian
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Jim Luedtke
Olรบfแบนฬmi O. Tรกรญwรฒ
3 months ago
"Nearly 80 years later, the simplex method is still among the most widely used tools when a logistical or supply-chain decision needs to be made under complex constraints." only half followed the description of the simplex method in here but super interesting anyways
www.wired.com/story/resear...
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Research Reveals the Optimal Way to Optimize
The leading approach to the simplex method, a widely used technique for balancing complex logistical constraints, canโt get any better.
https://www.wired.com/story/researchers-discover-the-optimal-way-to-optimize/
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Jim Luedtke
Bartolomeo Stellato
3 months ago
New preprint! ๐ Data-driven convergence guarantees for first-order methods via PEP + Wasserstein DRO. Less pessimistic probabilistic rates that reflect how your solver actually behaves ๐ฏ ๐
arxiv.org/abs/2511.17834
๐ป
github.com/stellatogrp/dro_pep
w/ Jisun Park & Vinit Ranjan
#optimization
#fom
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Jim Luedtke
Mark Copelovitch
3 months ago
Care about gun control? Climate change? Gun control? Abortion rights? Gun control? Universal health care? Gun control? Higher education funding? Gun control? Abolishing ICE? Gun control? Ending murder on the high seas? Gun control? Etc. Your platform is <institutional reform>
add a skeleton here at some point
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Jim Luedtke
John May
3 months ago
After 18+ years working for Maplesoft, I was "downsized" on Black Friday and I am currently on the lookout for new opportunities. I will be looking in earnest in the new year, but any leads on math programming/teaching work (especially in Los Angeles) would be appreciated.
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Jim Luedtke
NPR
3 months ago
As newsrooms shutter and paywalls rise elsewhere, public media delivers critical, unbiased reporting without fear or favor. That's the promise of a free press in a democracy. Click here to support the network of voices that keeps our public conversation honest and informed:
n.pr/4pCcFIx
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Jim Luedtke
Ellen Vitercik
4 months ago
Iโm excited to share the materials from my Stanford seminar course, โAI for Algorithmic Reasoning and Optimizationโ:
vitercik.github.io/ai4algs_25/
. It covered formal algorithmic frameworks for analyzing LLM reasoning, GNNs for combinatorial/mathematical optimization, and theoretical guarantees.
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Jim Luedtke
Guillaume Dalle
4 months ago
โ ๏ธ WANTED: PhD student โ ๏ธ The topic? GPU-friendly algorithms for discrete optimization and mathematical programming, to be used inside decision-focused learning pipelines. The mentors? My colleague Axel Parmentier and myself. [1/3]
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Jim Luedtke
4 months ago
Along with advancing optimization and game-theory research for post-disaster aid, Prof. Michiniโs NSF CAREER Award supports new courses and researcher visits to help students learn the field: โI want to break that barrierโฆbetween professors and students..."๐
go.wisc.edu/zeuiau
@uwmadison.bsky.social
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Michini will use CAREER Award to improve post-disaster aid operations and more - College of Engineering - University of Wisconsin-Madison
While Carla Michini and her family took their usual summer trip to her native Italy in 2025, this was no relaxing getaway. Michini, an assistant professor of industrial and systems engineering at the University of...
https://go.wisc.edu/zeuiau
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Jim Luedtke
Ben Grimmer
4 months ago
Lately, I have been obsessed with developing theoretically based optimization algorithms that actually attain the best practical performance. Alas, the classic model of minimax optimal methods is overly conservative; it overfits to tune its worst-case. We found a path forward 1/
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Jim Luedtke
arxiv math.OC
4 months ago
Alberto Del Pia Projection-width: a unifying structural parameter for separable discrete optimization
https://arxiv.org/abs/2511.02990
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Jim Luedtke
arxiv math.OC
5 months ago
Anna Deza, Georgina Hall Sum of Squares Submodularity
https://arxiv.org/abs/2510.24550
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Jim Luedtke
Sophie Huiberts
5 months ago
The simplex algorithm is super efficient. 80 years of experience says it runs in linear time. Nobody can explain _why_ it is so fast. We invented a new algorithm analysis framework to find out.
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Beyond Smoothed Analysis: Analyzing the Simplex Method by the Book
Narrowing the gap between theory and practice is a longstanding goal of the algorithm analysis community. To further progress our understanding of how algorithms work in practice, we propose a new alg...
https://arxiv.org/abs/2510.21613
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Jim Luedtke
Mark Copelovitch
5 months ago
Any serious future for democracy in America requires us to get rid of single-member districts. It is the only long-term solution to this nonsense.
add a skeleton here at some point
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Jim Luedtke
5 months ago
๐ Our very own Professor Laura Albert has been named a 2025 INFORMS Fellow! This prestigious honor recognizes her outstanding contributions to operations research, analytics, and data science. ๐ก๐ Weโre so proud of you, Laura โ keep changing the world! @INFORMS
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Jim Luedtke
Erling D. Andersen
5 months ago
@sophie.huiberts.me
is featured in a Quanta magazine article about the simplex method.
www.quantamagazine.org/researchers-...
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Researchers Discover the Optimal Way To Optimize | Quanta Magazine
The leading approach to the simplex method, a widely used technique for balancing complex logistical constraints, canโt get any better.
https://www.quantamagazine.org/researchers-discover-the-optimal-way-to-optimize-20251013/
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Jim Luedtke
Guillaume Dalle
5 months ago
Periodic appreciation post for this gem of a review by Hannah Bast and coauthors. If you think you know how to compute shortest paths... trust me, you don't. I can give you one spoiler though: preprocessing the graph helps A LOT.
doi.org/10.1007/978-...
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Jim Luedtke
Thiago Serra
5 months ago
@jannisku.bsky.social
is giving a very interesting talk on explainable (integer) optimization at the
@euroorml.bsky.social
seminar, highlighting counterfactual explanations before diving on new work with Coherent Local Explanations for Mathematical Optimization (CLEMO):
arxiv.org/abs/2502.04840
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Jim Luedtke
Jeff Linderoth
5 months ago
We are hiring two faculty positions in ISyE at UW-Madison Please come and join us!
jobs.wisc.edu/jobs/assista...
jobs.wisc.edu/jobs/assista...
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Assistant/Associate/Full Professor in Industrial & Systems Engineering (RISE AI) - Madison, Wisconsin, United States
Current Employees: If you are currently employed at any of the Universities of Wisconsin, log in to Workday to apply through the internal application process.Job Category:FacultyEmployment Type:Regula...
https://jobs.wisc.edu/jobs/assistant-associate-full-professor-in-industrial-systems-engineering-rise-ai-madison-wisconsin-united-states
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Jim Luedtke
Kevin M. Kruse
6 months ago
"Republicans run the entire government but can't keep it open" That's it. That's the whole story.
add a skeleton here at some point
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Thiago Serra
6 months ago
Here is a list of Winter / Summer schools on AI, data science, optimization, and related topics in operations research happening between October of 2025 and February of 2026:
thiagoserra.com/2025/09/22/w...
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Winter 2025 / 2026 schools on artificial intelligence, data science, machine learning, optimization, and other relevant topics in operations research
Following up on a recent post about Summer 2025 schools, here is a new list. The purpose of organizing this is to help graduate students find a summer school to gain skills related to operations reโฆ
https://thiagoserra.com/2025/09/22/winter-2025-2026-schools-on-artificial-intelligence-data-science-machine-learning-optimization-and-other-relevant-topics-in-operations-research/
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Jim Luedtke
southpaw
6 months ago
settings > content & media > autoplay video & gifs = off
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Jim Luedtke
Bartolomeo Stellato
6 months ago
๐ข New in JMLR (w
@rajivsambharya.bsky.social
)! ๐ Data-driven guarantees for classical & learned optimizers via sample bounds + PAC-Bayes theory. ๐
jmlr.org/papers/v26/2...
๐ป
github.com/stellatogrp/...
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Jim Luedtke
Thiago Serra
6 months ago
I wrote a tutorial inspired by my experience conducting research with undergraduate students who knew how to code, but were yet to learn about optimization. What is the Best Way to Do Something? A Discreet Tour of Discrete Optimization:
github.com/thserra/disc...
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GitHub - thserra/discreet: What is the Best Way to Do Something? A Discreet Tour of Discrete Optimization
What is the Best Way to Do Something? A Discreet Tour of Discrete Optimization - thserra/discreet
https://github.com/thserra/discreet
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Jim Luedtke
Ben Recht
7 months ago
I wrote about the tragic death of Adam Raine and the venal negligence of "AI Safety."
www.argmin.net/p/the-banal-...
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The Banal Evil of AI Safety
Chatbot companies are harmful and dishonest. How can we hold them accountable?
https://www.argmin.net/p/the-banal-evil-of-ai-safety
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Jim Luedtke
Mark Copelovitch
7 months ago
Nobody covers Wisconsin politics better than
@danshafer.bsky.social
& you should take advantage of this great deal
add a skeleton here at some point
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Jim Luedtke
Prof Christina Pagel
7 months ago
Israel had every right to respond to Hamas' 7 Oct 2023 attacks. But this has NOT been a proportionate response: it has been an escalating campaign of war crimes, crimes against humanity & genocide as the world just watches. It is fair to hold Israel to a higher standard than Hamas terrorists. 5/5
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Jim Luedtke
Thiago Serra
7 months ago
The
#FutureBAProf
workshop continues with Tallys Yunes, the 22-time winner of University of Miami Herbert Business School Excellence in Teaching award, sharing about teaching in business schools. 1/2
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