Sprint guys, explain the .10 rule. Is the tolerance on the machine even .001?

Wejo,

There should be a stated uncertainty in the instrumentation measurement. It is the problem we get in science all the time with digitization- just because an instrument can report 10+ digits doesn't mean that that is the actual measurement uncertainty.

in my book, there should be a recorded measurement uncertainty to what the sensor can report. (A machine that applies pressure and release to the system and then look at what the variability in the reported values would be would easily give you a confidence interval for the measuring, and that assumes that the clock timing of the processors is accurate to whatever nanoseconds they seem to be thinking they can report (so there is the physical response of the sensor plus the loop time of the code and the processing speed of the equipment to account for).

While the paper says that 0.1000000 or whatever number of zeros is the theoretical limit, that would then have an applied uncertainty of the measurement equipment (scale to the real world) to go with that theoretical value.

In my mind, the USATF should absolutely be filing a protest since if they really are taking a reaction time.of 0.099999 or whatever and the uncertainty of the measurement is even +/- 0.00001, this rounds to 0.01000 +/- 0.00001 with the last digit being the first uncertain digit (where the confidence interval is applied). For instance, depending on the chips used, the resolution of the timing circuit could be 1ms (it's probably better than this for professional timing systems, but at the same time, the code for doing this will.run in some sort of loop and the sensors will have a given response time as well. The error will be convolution of all of those factors.)

At the very least this as a scientific basis form those numbers need to be applied to how that rule is written and applied. I for one doubt that the pressure release on those sensors and all of the equipment in the timing can be relied on to that degree of accuracy.

Just my opinion. The way they are reporting those numbers in my mind indicates that they are commiting the common sin of carrying too many digits into the final answer and not applying the error propogation (sorry, the inner professor in me is screaming). :)

So he got DQ for starting too soon AFTER THE GUN went off. Um, what?

No, that's totally incorrect. The "gun" sound isn't from a gun. The gun sound is from individual speakers, and one speaker is placed directly behind each starting block.

Wejo, I’d encourage you and others to dig into why the reaction times seem to have been universally quicker across multiple events so far than in any recent championship or Olympic event. I mean, in the hurdles final, we had two .11s and two .12s alone. The reactions in the 100s were also unusually fast. Coleman had a .104. Allen was around .100 twice.

i think this is one of those things that we can get a math guy involved, throw data at them, and we can work backwards and theorize VERY strongly that your hypothesis that there is a system error is correct.

With a registered name of "SCRunner" on a running site, you're obviously a runner. Are you saying that even though you're a runner, you have no idea how false starts are determined?

Also, a reasonable inference can be drawn that if so many false starts are *marginally* under .100, yet, we are having no anticipations in the .08, .07 range, etc., that one of two things may be true:

1. the timing measurement is similarly marginally incorrect; or

2. the theory that .1 is the limit for human capability is fundamentally flawed;

or 3. Both.

That's a good idea. Take every reaction time from every runner in every race in these championships, and compare it to the reaction times of every runner in the last few global championships, and see if there is a difference in reaction time that is statistically significant.

Another variable needs to be the reaction times of these runners in these championships compared to their past reaction times - and maybe we can start to see a pattern emerge with enough data points as to how much the measurement may be incorrect by.

Old thread where this was discussed

I'm pointing out that it's lame. Why bother to have a gun start the race then, let's use starting gates like horses.

Cute reply by the way. I bet you find yourself amusing.

A far more likely scenario is that Devon Allen anticipates the gun. Officials know this and have gotten tired of it.

What you sniffing these days, Bruv?

I sat above the 100m start line for the morning session (which had the Hep 100H) and noticed that the large Seiko speakers were not behind every lane. You can see in the NBC twitter vid on the homepage that that appears to have been the same setup for the evening session. There are three large (toaster sized) speakers placed between lanes 1-2, 4-5, and 7-8.

He anticipates the gun and is consistently right at it and never significantly early? Doesn’t pass the common sense test. He just has good reflexes. The simplest explanation. He would be false starting a lot more I feel if your hypothesis was right.

looking back at doha '19 right now. something is clearly going on with the reaction times here.

and the thing is, it's so obvious that i guarantee you there are officials with the timing company shting themselves right now.

this doesn't take some grand mathematician. go look at the data for yourself. something is clearly going on in eugene. reaction times are faster across the board. it's not even close.

further, looking at london wc 2017 and seeing false starts of "-0.050, .053, -0.13" between the men/womens 100 and 100h/110h. that is a more even distribution as one would expect for false starts.

compare that to the four false starts in eugene so far: .092, .095., .096, .099

and across the board reaction times are down by about .02 compared to past world champs. it was pretty rare to see someone under .13 until Eugene and suddenly that's the new normal? nice try.

if officials don't say something about this tomorrow, they are either covering it up, incompetent or both.

this is a timing mat issue, though. hope they have good insurance, cause this is lawsuit worthy negligence/incompetence or whatever the proper legal term is. mfers messed up big.

getting the same sort of data from Beijing 2015: reaction times on average appear to be ~.02 faster in Eugene than Beijing

here are some false starts i found in beijing: -0.048, -0.024, .053, 0.071

there were also a few others with no time next to just the infraction of R162.7 noted, which i assume means the starter never even fired the gun so there was no -0.xxx to note.

but again look at the distribution of false starts, it's even. not clustered like in eugene.

lawsuits in 3...2...1...

Any idea if these are the same exact set of starting blocks that were used at the recent NCAA and USA Championships?

Or did they get brand new ones specifically for the World Championships?

I'm asking because I'm wondering if a lot of the reaction times at those two events were also close to .10 seconds ?

wejo, see my previous post (if you can search that) in a different thread.

Eugene 110mH semi-finals have a 16.1 thousandths faster "average" (mean) reaction time than Toyko semi-finals.