MathBunny

Hey, I made a site a year ago that determines how wind affects segment efforts. I'm currently redoing the site and looking for some feedback, I made it much easier to use and it generates a correlation score, which indicates how much the wind helped you (higher => wind helped you, negative => wind didn't help).

Here's the link: Wind Analysis

San Pedro

Couldn't get My API settings from Strava, didn't have that option in my settings page. I'm rather interested as I live in a windy area, and I know that wind is a huge factor in my segments.

MathBunny

Wait did you click login or did you click legacy? If you click login it does everything for you, you just need to authorize the app (it's a normal Strava login). Legacy is my old site

San Pedro

I did legacy, I'll give it a go before I fall asleep. Now, does it let you see other riders performance too?

Edit: just looked and it does... Super cool!

MathBunny

Yeah, it shows the top-10 + the nearest athletes to you in the segment leaderboard. If you're in top 10 then it just shows top 10.

Quiglesnbits

Well I just loaded it and looked at a segment that I know I had a headwind on today. The program told me the wind was coming SSW (correct), but that I was riding NE (Not correct).

Segment number is 6865608

MathBunny

Okay, I'll look into it, thanks!

Quiglesnbits

No problem, as an additional question. Do you have a goal for what the scale of the context number means? like, is 0 to 1 a 2 mph wind, is 2-5 a 10 mph wind? that sort of thing?

MathBunny

My goal is to make that number related to km/h such that I can eventually sort the leaderboard by factoring in wind. Of course it's terribly inaccurate but I was looking at some empirical experiments and I ran a few regressions and this is what I came up with, but from my observations the numbers doesn't look right sometimes so for now it's just a ballpark!

I'm also looking to add miles per hour in settings to support users outside of the metric world btw.

MathBunny

Fixed the issue!

Quiglesnbits

Still saying the wind helped me though.

MathBunny

Hmm, if the wind is coming from SSW, and the ride's direction is SW, doesn't that mean that it should help you?

Quiglesnbits

No, that means the wind is blowing somewhere around 22.5 degrees off my front, towards me. From the SSW means towards me riding TO the SW.

MathBunny

I see, got mixed up, okay I'll investigate, thanks!

jcro001

This is a really interesting site you've created. Would it be possible that when I click my name in the Segment Leader board, it would show me my rides on the segment? Currently the Segment Leader Board seems clickable (mouse pointer changes to finger) but when I click nothing happens.

MathBunny

Good idea, I'll add that on my TODO list, thanks! Also it does nothing, the mouse changing should be fixed. Thanks again.

DrIsotope

This is pretty cool. I can assuage myself on some of my KOM losses-- I lost one recently, and my effort on the segment had a wind assist of -6.45, and the new KOM has a +4.77. I'm the only person in the top 10 with a negative number.

MathBunny

Update: Over 1000 users joined, I ran out of weather API keys. If you want to use it you have to wait a few hours

PM City

Kudos! I think this is awesome. I look forward playing around with it.

nycphotography

Clever idea


Instead of an influence rating, why not use kreuzotters bike power math to back out power (with cosine of wind), and then work the power back forward with zero wind to calculate a "wind adjusted speed". And time.

laf

mywindsock.com

canklecat

Interesting. Not sure what to make of the data. One of my fastest segments (only 3rd and far from the KOM) was definitely wind assisted. The segment is 1.3 miles long, mostly downhill, heading north by northwest, with a 15 mph wind out of the south/southeast. Yet the data shows an influence of -0.03. I would have expected at least a small positive number from the wind assist.

And the wind is consistently out of the south on that segment, so it's predictable. Most of the other riders on that segment show at least some positive number, acknowledging the wind assist.

OTOH, if the data are accurate, the guy who holds the KOM will be pleased to know he got very little wind assist. But he's a beast anyway.