Comment by jliszka | Hacker News Reader

Comment by jliszka | Hacker News Reader

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> You can see on the right side how his "cars per second" is _exactly the same_ than on the left side.

Yes, but there are way more cars on the left side. That is the difference. Occupancy (density) determines speed when flow rate is fixed, and that graphic is actually a perfect illustration of this. You can't make the cars on the left travel at 80mph because it would not allow for a safe following distance.

One thing that is the same on both sides is that if you're the nth car back from the merge, it's going to take 2n seconds for you to get to the merge. Yes, the important thing is how many miles you can cover in that time, but this way of thinking places an upper limit on how many miles that can be, based on the occupancy of the road.

Also, pretty sure the advice at the end was tongue-in-cheek ;)

I'm sorry for the harsh critique. I think new radical ideas are great and people should question everything that's out there. But this way was not thought out well enough IMO.

I hope you keep it up and maybe have a follow up post where you can fix some of the flaws.

Some of your ideas are correct and noble. But always remember to take into account the real world driver and his/her behavioral flaws.

Few thoughts: Interesting would be a stochastic behavior model of drivers + driving strategies and in connection with red lights, accidents, rush hour to see what happens. Thought, that model would be quite some work in python.

Cheers

Really appreciate the feedback, comes with the territory :)

I added an update to the article looking at what happens when you vary the average car length (corresponding to the % of trucks on the road), fwiw.

I just read some of your older blog posts. They're close to my research and well written and very informative. Keep up the good work!

Cheers

Thanks! What's your research on?

> I added an update to the article looking at what happens when you vary the average car length (corresponding to the % of trucks on the road), fwiw.

That's silly, at most reasonable traffic flow-rates the difference in a couple of feet between a short car and a long car (esp with how uncommon the outliers are) is insignificant compared to the constant overhead of the per-car padding. And below reasonable traffic flow you're already at a high enough density to cause catastrophic traffic speeds.

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