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How Factoring works in Alpine Skiing at PyeongChang 2018

Date 10-Mar-2018

(Getty Images)
Have you ever wondered how an Alpine skier with one arm competes in the same category as someone with spastic paraplegia or how an athlete with no sight at all races fairly against a partially visually impaired opponent in the downhill? If so, the answer is the sport's factoring system.
It is a carefully calibrated method, which is honed annually and takes into account reams of historical race data. Ali Bombardier a World Para Alpine Skiing race director form Australia answers  all.

What is the factoring system?
We have visually impaired, standing and sitting groups but within those groups we have different levels of impairment and the factor they get given evens out the playing field.
So it is to enable someone who is completely blind to race the same course as someone who has 10% vision - the person who is totally blind has a bigger percentage (factor) so doesn't have to go as fast to win because their finishing time is adjusted.
How is it worked out?
The percentage is worked out off historical data. We have collected all the data over the many years of (para) Alpine skiing and it has been worked out to enable everyone to win a race.
Is it a personal or group-wide measurement?
It is within the groups. We have nine standing groups, three visually impaired groups and three sitting groups and each group has a factor associated with it.
And it's different for each discipline - one for slalom, one for GS (giant slalom), one for super-G and so on. That takes into account, for example, that the slalom has short, sharp turns so that is easier for some to do than others and the downhill might be the opposite.
Is it constantly updated?
Yes. Every year we look at results, we have an expert group of people who are very good at mathematics. They look at it and look for outliers. If we have someone from a class who all of a sudden starts winning by a huge margin, this outlier will pinpoint that maybe the data isn't correct.
The more data we get the better it gets. It's better now than it was 15 years ago and it will continue to get better.
It's not a perfect system but it's a good system and it enables us to run good, fair competitions and really push the athletes to excel.
Is it a complicated calculation to work out each factor?
The background to it is, but the actual factor is a simple percentage. We have an Excel table with the percentages for each group, so depending what class you are in you can look across and see that to win the race you need to be 0.13% faster than everyone else.
The actual maths is quite easy but it's the background and collecting of the data that is a bit more complicated.
Who is in this expert group?
Right now we have a couple of academics. They are volunteers but they also understand the ski racing and Paralympic side of it. And we also have some people from within the IPC (International Paralympic Committee) that help.
Is everyone happy with the system?
There is some grumbling in certain places, but our system is pretty good and it's pretty fair across the board. Sometimes you will hear coaches or athletes complaining but that's good because then we look at those highlighted points and we can either confirm that, 'Yes we had a problem' or look at it and go, 'No, we are OK'.
The hard thing with our sport is we have so many other variables that affect any ski racer - the weather is different, the snow conditions are different, the hills are always different, the course settings are always different - and then you throw in a single percentage to even things out and sometimes it doesn't.
We are controlling the one variable we can control. Unfortunately we are not in a swimming pool that is always 50m and always 23 degrees Celsius.
Are results ever adjusted after the race?
No.
Are the factors ever adjusted during the season?
No, never. Once the factors are set, they are set. And they don't get changed every year, it's just if an outlier comes into play.
In terms of finish times, what do the spectators and TV audiences see?
It is always the factored time. You will never see what you call the 'raw time'. On the big screen (at the finish area) and the TV screen, you see the factored time.
Every racer will have a general idea of what they need to aim for - for example, my factor is 85% and his is 90%, so I need to go 5% faster to win.
 
(Source OIS)