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Yes there can be, because people who hop in and out of the HOV lane don't traverse all lanes every time they do it.

For example, Alice gets on the freeway and merges 4 times (after the initial merge) to get to the "fast lane". For ease of explanation, the lanes will be referred to like this:

  | HOV | 5 | 4 | 3 | 2 | 1 | Onramp |
(So lane #5 is the fast lane in this example)

Traffic starts slowing down, so she merges from lane 5 to the HOV lane in order to pass a few cars. She's in this lane illegally so she doesn't remain in this lane. After a few passing a few cars, she merges back into lane 5. She repeats this 3 more times before she gets off the freeway.

So, in this limited example, this is the "transaction count" of Alice's lane changes:

  Onramp <-> Lane 1 : 2
  Lane 1 <-> Lane 2 : 2
  Lane 2 <-> Lane 3 : 2
  Lane 3 <-> Lane 4 : 2
  Lane 4 <-> Lane 5 : 2
  Lane 5 <-> HOV : 8
The problem isn't people just getting over to the fast lane, staying in it and leaving, the problem is the number of transactions that the HOV <-> Fast lane pairing have due to it being relatively empty even during crowded freeway conditions.

Similarly, lanes 1 and 2 have higher transactions due to people getting on the freeway for a mile or two and exiting shortly thereafter. This may be limited to AZ freeways since the exits tend to be regularly spaced about a mile apart. The other problem is that there are quite a few people who will merge on to lane 1 going 45MPH, which causes many drivers to pass them in Lane 2.

Chronic lane changers seem to use all lanes roughly equally, so their habits mostly cancel out.

Another thing that may be different depending on where you live is that AZ allows entry and exit from the HOV lane at any time. It's not like CA where there are specific entries and exits to the HOV lanes.

Let me know if this still doesn't make sense.




This still does not make sense

  Onramp <-> Lane 1 : 2
  Lane 1 <-> Lane 2 : 2
  Lane 2 <-> Lane 3 : 2
  Lane 3 <-> Lane 4 : 2
  Lane 4 <-> Lane 5 : 2
  Lane 5 <-> HOV : 8
So the total transactions for lane 5 is 10 and HOV is 8. This is not a counterexample to what I stated.


By "fast lane", I believe icey is refering to lane 5, not HOV. He is saying lane 4 is better than lane 5 because of all the people switching between land five and HOV. He's not saying that lane 5 is better than HOV.


Thanks




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