JSJeevika Sinlocal-minima.hashnode.dev·2d ago · 10 min readBuilding an RL Traffic Agent for Indian Roads, Part 8: The Ramp That Wouldn't Go AwayPart 7 ended on a table that looked clean. Nav scaling fixed the steering lock-in, extending training to 100,000 steps gave the CNN room to actually learn road geometry, and every metric in that closi00
JSJeevika Sinlocal-minima.hashnode.dev·2d ago · 7 min readBuilding an RL Traffic Agent for Indian Roads, Part 7: Unlocked, and Immediately Falling Apart DifferentlyThe critic had curvature. The actor finally had somewhere to go. Which meant, for the first time, the car actually moved. It also meant a new set of problems, because "moving" and "driving well" turne00
JSJeevika Sinlocal-minima.hashnode.dev·2d ago · 13 min readBuilding an RL Traffic Agent for Indian Roads, Part 6: The Frozen RobotEverything in Part 5 worked. The pipeline ran end to end, LIDAR in, occupancy grid out, latent vector through the actor, continuous steering and throttle out the other side. Then I actually let it tra10
JSJeevika Sinlocal-minima.hashnode.dev·2d ago · 18 min readBuilding an RL Traffic Agent for Indian Roads, Part 5: The Math, the Bugs, and Everything That BrokePart 4 was the reasoning that got me to an architecture on paper. This part is what happened once I actually tried to build it, which turned out to be a very different exercise. Most of Part 4 was "wh00
JSJeevika Sinlocal-minima.hashnode.dev·2d ago · 19 min readBuilding an RL Traffic Agent for Indian Roads, Part 4: The Architecture After going through the theory, I didn't want to just jump into code. I wanted a base to build on first, a shape for the whole thing before I touched a single line of Python. So the first question I h00
JSJeevika Sinlocal-minima.hashnode.dev·2d ago · 8 min readSelf Driving Cars, Part 3: Building a 2D Simulator to Understand RLAfter going through the self-driving landscape, Tesla, Waymo, BYD, and the rest, covered in the first two parts of this series, I spent a couple of weeks studying the architecture and approach compani00
JSJeevika Sinlocal-minima.hashnode.dev·3d ago · 8 min readSelf Driving Cars, Part 2: It's Not Just Tesla vs WaymoPart 1 was Tesla vs Waymo, and by the end of it I'd landed on Tesla, mostly because of how the two scale. But somewhere in my own head after publishing that, I realised I'd boxed myself into a pretty 10
CMChaeyeon Mia Leeinmiainflorence.hashnode.dev·Aug 3 · 9 min readWhy GRPO, Dr. GRPO, and DAPO Are All the Same Algorithm in Disguise: The Group-Standard-Deviation IdentityYou've spent hours tuning your RLVR training run. GRPO converges too aggressively on hard problems. You switch to Dr. GRPO for stability, but then you read that DAPO gets better results by throwing aw10
YSYusuf Solomoninysolomon.hashnode.dev·Aug 1 · 18 min readImplementing Algorithms for the Multi-Armed-Bandit ProblemLet's suppose you are faced with a dilemma; there are k possible actions to take, and you have only T opportunities to take actions. Taking an action returns a reward R from an underlying reward distr00
MMikuzinmikuz.hashnode.dev·Jul 31 · 8 min readA Practical Guide to Reinforcement Learning EvaluationReinforcement learning has emerged as the preferred method for the final phase of large language model post-training, with systems like DeepSeek-R1 and OpenAI's o-series demonstrating capabilities bey00