Increased wkg accuracy

Is it possible to get ZP to show 2 decimal places instead of the standard 1 in the avg/20m/5m/1m/15s columns? I think this would offer a higher degree of accuracy if it also started using calculations based on 3 decimal places rather than 2.

example of this is me, a 70kg rider putting out 319w, ZP shows this as 4.6wkg but in reality it is 4.557wkg so ZP rounds up or down based on the 2nd decimal, if it was calculated to the 3rd decimal it would show 4.56wkg which is a completely different and more accurate reflection of that rides power, it’s this sort of rounding up that bumps people up categories.

The minimum category shows 2 decimal places on the 95% of 20min as do the numbers for the 15s/1m/5m/20m power, putting it to 2 decimal places on the columns would make it a bit more uniform, again using myself as the example with my 5min power, my number shows 5.45wkg but the 5min column shows 5.5wkg, its only a few watts but i think we all want accuracy when racing and viewing the race metrics.

Can you explain to me why this is needed?

Categories are done to 3 decimal places. The view 95% toggle also shows w/kg to 3 decimal places. I’m afraid I’m struggling to see any value in this request.

for greater accuracy, as I said last night I did 4.557wg in a race, ZP has this down as 4.6wkg in the 20min column which is inaccurate, if it is being calculated to 3 decimals why is it rounding up the 20min column to 4.6 from 4.557, that to me is not using 3 places but 2 as it sees 4.55 and bumps it to 4.6, some of the values might be going to 3 decimals but not all of them, ZP is rounding it up to an inflated number given that 4.557 is nowhere near 4.6, personally though I’d rather see 4.56 than 4.6 as its a truer reflection in the 20min column

this is the sort of thing done to 3 decimal places

compared to what it currently is

as you can see there is a difference where numbers are being rounded up or down which aren’t a true number, I was requesting a greater accuracy in these numbers being displayed

Yes, but what do you gain from this? You seem to be asking for data for datas sake.

I get that something rounded to two decimal places is more accurate, but I don’t think you actually gain anything from it.

Also, it’s not inaccurate, it’s obeying the laws of mathematics.

FWIW if other’s think this is a good idea idea, I’m all for getting it raised, but I’m not really seeing how it will enrich the ZP experience.

to get a better sense of accuracy from ride data as I have explained several times, intervals.icu doesn’t do this rounding up that ZP does but if nobody else would find it useful having a more accurate assessment of their rides then that’s fine and i’ll stick to intervals.icu for accuracy

Does the power section help?

3.55 to one decimal place is 3.6. It’s displaying the information correctly but I understand that you want it to report the the next decimal place. I’m genuinely not trying to be difficult :slight_smile:

Typically the precision difference is less than 1% by adding a decimal point, which maybe is within the variability and precision day-to-day of most power meters anyway?

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If you are on the edge of a category and want to know what is needed to move categories then W/kg to 2 decimal places increases accuracy significantly.

But surely it shouldn’t matter if you’re on the edge of a category?

If you continue to perform well, you will be duly rewarded with a cat upgrade and that should be encouraged and applauded.

If more accurate w/kg values are being requested in order to avoid an upgrade well that’s a different matter entirely.

BTW, I’m not implying that this is your raison d’etre John, so please don’t take it the wrong way. I’m simply playing devil’s advocate here.

I agree 100% with your thoughts. There is a large group of people who carefully manage their category, particularly for the ZRL. It makes the difference between competing and coming last for some. The morals of this can be questioned, but preventing accurate calculation won’t change much. I was just providing an example of a reason for more accurate data. The best answer is probably to avoid step changes in categories.

a better reward would be to just stay in B so i dont catch rhabdo by trying to hold the wheel of a 60 year old man with a 500w FTP on an elite muin. so for this reason i think ZP should round down every number to the lowest integer

Indeed. With B due to the upper limit at least extremes are cut off. While someone might not be as strong as their numbers imply at least it has to. E within limits. In A there was an old Pogacar with 6.6wkg FTP and 1000 watts for a minute. Sure, gets disqualified after the fact almost always but it still ruins the game. Unfortunately there are plenty so it’s not the exception. With such things not fixed B racing will be superior to A for random races during the week (and better attended, maybe because of this).

Category enforcement is great in theory but A feels like a big mess as all the extremes with cheating, buggy trainers etc can run wild and rampant there.