# 计算打卡类型偏差

Calculating tick shift is scientifically based on analysis of almost a million climbers ascents. The results presented in this article are preliminary. Over the coming months we will be gathering climber feedback which we fully expect to challenge us. We fully expect to change these as we learn more.

We had a lot of false starts with the analysis, because it turns out that tick shifts are grade dependent. However for various reasons, the first release we are picking a constant shift based on higher grades.

Running all theCrag ascents through our tick shift algorithm we get the following tick shift graphs for Ewbanks and V-scale grades, with the shifts represented in an internal grade (1 Ewbanks grade = about 15 internal grades).

Please note that trad pink pointing is not so common and there is indication that there may be a bias in the pink point results which we don't fully understand yet. Using different analysis techniques, pink point tick shift may be a lot higher, in particular for trad. Basically expect the pink point shift to change, but for now we are just making the trad and sport pink point tick shift the same.

Tick shift analsys results for Trad ascents

Tick shift analsys results for Sport ascents

Tick shift analsys results for Boulder ascents

In hindsight, the grade dependency makes sense because a climber is probably starting off top roping and seconding and when they start leading it is climbing stuff within their ability, which ends up being an onsight. At the lower grades red pointing is more about doing a climb on the second or third attempt then coming back day after day and working the route.

Flash is consistently about half to three quarters of a Ewbanks grade above an onsight.

pink pointing grade dependency is also to be expected because at higher grades the distinction between pink points and red points disappears. At the very highest grades most climbers would consider a successful ascent with pre placed gear a red point tick. So what we are seeing is this bias in the community.

The following is a representation of the tick shifts we implemented:

AU
16 17 18 19 20 21 22 23 24 25
FR
5a+ 5b 5b+ 5c 5c+ 6a 6a+ 6b 6b+ 6c 6c+ 7a 7a+ 7b
UKT
4c 5a 5b 5c 6a 6b
YDS
5.8 5.9 5.10a 5.10b 5.10c 5.10d 5.11a 5.11b 5.11c 5.11d 5.12a 5.12b

Figure: Trad tick shifts

AU
16 17 18 19 20 21 22 23 24 25
FR
5a+ 5b 5b+ 5c 5c+ 6a 6a+ 6b 6b+ 6c 6c+ 7a 7a+ 7b
YDS
5.8 5.9 5.10a 5.10b 5.10c 5.10d 5.11a 5.11b 5.11c 5.11d 5.12a 5.12b

Figure: Sport tick shifts

BLDV
V0+ V1 V2 V3 V4 V5 V6
FB
4C 4C+ 5A 5A+ 5B 5B+ 5C 5C+ 6A 6A+ 6B 6B+ 6C 6C+ 7A

Figure: Boulder tick shifts