Furthermore, the comparison of current road speed to average road speed, for the purposes of traffic congestion reports, may not be using a time-window average speed, but a net average speed for the road.

We only get one average for the road map. Even if the routing is using a time-window, it may be too much of a server load to use a time-window average for traffic congestion.

By observation I'd be certain that traffic congestion is based on a total average road speed at all times.

That is, 25 km/hr is slow, based on the average 100 km/hr and will generate a heavy traffic report.
Even though the average speed +/- 2 hours of the time is 18 km/hr.

deeggo wrote:I would really like them to confirm it...

That would be nice, but I doubt it. As well as subject to change, I expect they might consider it a competitive advantage.

deeggo wrote:However, I haven't seen the traffic jam not showing anymore when it's there daily

What do you mean by "traffic jam". A traffic jam road report is manually generated. I would expect a complete standstill road report will always be generated, as the average road speed will never fall to zero. And in the event of a complete standstill Waze does all it can to avoid that road. So even if it is a t a complete standstill every day at that time I'd still expect to get a standstill report? Is that what you mean by "traffic jam"?

To put it another way, are there any roads where you see "heavy traffic" congestion reports at the same time every day for a month?

deeggo wrote:

waynemcdougall wrote:To put it another way, are there any roads where you see "heavy traffic" congestion reports at the same time every day for a month?

I see some congestion reports - indeed that's what I meant - reoccur every day. It's not that I'm keeping a list, but yeah, they're there practically every day.

Well I do keep a list. So this morning, I see a traffic congestion (heavy traffic 25 km/hr ) at 0906 hours, as the traffic was heaveir than usual and so extended further in time. And I see moderate traffic on another stretch (18 km/hr) where the speeds are always slower at this time.

So what is heavy and moderate does change according to what is expected at the time of day. And traffic congestion reports have reduced at times that we expect to be congested.

It's impossible to judge these things without a record. All human's have selective recall bias. What I see from actual records is exactly what I would expect based on my mental model of how it should work. Over time Waze learns expected traffic density at expected times, and reports if it is abnormal from expectations.

I like exception reporting. Life is too cluttered with information. Just tell me the unexpected problems. Not the expected problems.