Operations Research Stack Exchange
Operations Research Stack Exchange

Most Popular

more tags
1500 questions
28
votes
5 answers

Why is open source operations research software so far behind open source statistics and machine learning software?

Like many who participate in this site, I work on projects in both operations research (OR) and statistics/machine learning (ML). The different states of open source software in these fields are often discouraging as an OR professional. In…
Robert Bassett
  • 625
  • 7
  • 12
28
votes
6 answers

How can I deal with non-operations research managers?

I am doing an internship in a company. The aim is to solve scheduling problems in the industry (a variant of the resource-constrained project scheduling problem). By the end of the internship, they will offer me a job opportunity. I will need to…
Antarctica
  • 2,917
  • 15
  • 34
27
votes
2 answers

How do you keep track of the latest publications in OR

It seems the most common answer to this question is: we periodically scan the websites of our favorite OR journals This approach however has several problems: you are likely to miss articles. you are likely to forget to do this on a regular…
Joris Kinable
  • 3,451
  • 8
  • 19
26
votes
3 answers

What are best practices to make optimization user interfaces intuitive for the user?

For many operations research applications a user will often be in charge of making the final decision and will use the optimization algorithms software as a part of their planning flow. Therefore, optimization software often needs a user interface…
Michael Lindahl
  • 1,659
  • 6
  • 22
26
votes
5 answers

What's the current status of the Vehicle Routing Problem in the logistics industry?

After a bit of reading I think I've been able to conclude that state-of-the-art VRP can get solutions for 100~500 stops. My question is around how this actually affects logistics (like Amazon for instance). Do they actually practically use these…
Alexander Soare
  • 433
  • 3
  • 8
26
votes
6 answers

Statistical tests for benchmark comparison

Suppose that you have two algorithms for solving an optimization model, and you want to benchmark their performance over a large set of instances (with only one performance metric, for example, the running time). I want to show that one algorithm is…
Borelian
  • 803
  • 6
  • 15
26
votes
5 answers

Solving pricing problem heuristically in column generation algorithm for VRP

In the set covering/column generation approach for the VRP (Balinski and Quandt (1964), or e.g. this tutorial), the basic idea is: Generate some routes. Solve the set covering problem using those routes. Generate more routes (using the dual values,…
LarrySnyder610
  • 13,141
  • 3
  • 41
  • 105
26
votes
1 answer

The rationale to improve MTZ?

Currently I need to solve a quite specific problem involving symmetric TSP as a sub-problem (i.e., a Hamiltonian cycle is a necessary condition for optimizing some problem-specific variables that should make use of that cycle). From the literature…
Omicron_Persei_11
  • 363
  • 2
  • 6
26
votes
4 answers

Stochastic programming MIP solvers

I am aware that Benders Decomposition is readily available in CPLEX and in SCIP; but are there any (free) solvers that provide off the shelf stochastic programming MIP algorithms or a nice to work with programming environment ?
Albert Schrotenboer
  • 1,859
  • 12
  • 27
25
votes
5 answers

Examples of machine learning applied to operations research?

Can someone give me a few examples, if they exist, of problems in operations research that could be solved using machine learning. I am aware that machine learning examples are data-driven and do not give exact solutions, so I am expecting…
klaus
  • 353
  • 2
  • 6
25
votes
7 answers

List of Implementations for common OR problems

For the TSP there famously is the concord solver (http://www.math.uwaterloo.ca/tsp/concorde.html) which is argubly the fastest exact solver for the TSP. There are many other problems that also show up again and again, for example the capacitated…
PSLP
  • 2,401
  • 9
  • 33
25
votes
8 answers

What are the main differences between Operations Research in the academic world, in the enterprise world and in the government world?

For anyone who's been on both sides of the fence: how does academic OR differ from OR in enterprises or governments?
Geoffrey De Smet
  • 4,851
  • 10
  • 34
25
votes
3 answers

What is the purpose of libraries like Pyomo and Google OR tools?

I'm new to the OR world, and trying to learn the various tools available. I originally thought that Pyomo and Google OR tools were open source alternatives to commercial solvers like Gurobi or CPLEX. But now I'm discovering more and more that they…
Skander H.
  • 2,139
  • 2
  • 11
  • 21
25
votes
6 answers

How to compare two different formulations of a problem?

I somewhat know how to compare two MILP formulations of a problem that both use the same set of decision variables (as in the classical MTZ vs DFJ formulations of the TSP). I was wondering how two formulations of a problem that use different sets of…
rasul
  • 2,140
  • 7
  • 23
24
votes
5 answers

OR-backed serious games

A "serious game" is a game (usually a simulation) designed for a primary purpose other than pure entertainment. Games like the beer game or the fresh connection can be considered serious games serving an educational purpose. Edited after comments My…
Libra
  • 937
  • 5
  • 14
1 2
3
…
99 100