Race Snapshot: Tour de Ski Classic Sprint

Sounded like a messy, crash filled sprint today. Exciting stuff!

Race Snapshot: Tour de Ski Pursuit

I sort of hesitate to post these, since as I expected this race format produces performance measures that are extreme outliers pretty much no matter what you do. Regular duathlon pursuits you can correct for somewhat, but these stage race two day affairs just always produce wacky looking results.

Liz Stephen’s Distance Preferences

I was skimming FasterSkier’s write-up of the Tour de Ski prologue yesterday and noted their comment about how Liz Stephen “… is generally stronger over longer distances, performing better in 10k’s than 5k’s and even better still in 15k’s.”

That has been my informal impression as well, but I was suddenly skeptical about whether her actual results would bear that out as clearly as you might think. Specifically, I started wondering whether this may be a situation where how you measure results has an impact on how we perceive their quality. For instance, here are her WC level distance races, filtered down to only 5, 10, 15 and 30 km distances, measured by finishing place:

In 2009, longer distances were definitely better. Then things looked kind of mixed in 2010 (generally an off year), before returning to normal in 2011. So far this season, this look fairly mixed again, although with only a single race over 10k.

However, the longer races (15k/30k) are usually mass start or pursuit races. They can sometimes have smaller field sizes and are often paced much slower. (Although I think the difference is probably not as pronounced with the women as it is with the men.) If we look at the percent behind the median skier, which corrects for some of the differences between interval and mass start races, we get this:

Things look the same for 2009: noticeably better at the longer distances. Now, though, 2010 doesn’t look “mixed”. Rather, it seems she skied quite a bit better that year in the 10k’s (again, having a generally off year). But then both 2011 and 2012 look fairly mixed to me, with some good races at several different distances.

So I think her results have displayed a modest tendency to be stronger in longer distances, but not quite as much as you might think by looking only at her finishing place.

Race Snapshots: TdS Prologue

Count me among the folks who aren’t sold on the idea of prologues.

European Mid-Season Review

This will just be a short note with similar graphs as last time, only for a few of the major European nations.

Men’s Distance

Sweden continues to generally improve. Note that in terms of top thirty performances, Norway has steadily declined over the years, but not among the top ten or better level. So they’ve become somewhat less deep of a team, but they still manage to crank out top results. Indeed, if anything they’ve been improving. After a couple stronger seasons, the Russian men aren’t off to a great start so far this season. Read more

North American Mid-Season Overview

During this lull before the Tour de Ski, I thought I’d show some graphs quickly summarizing how the US and Canada have fared thus far with some historical context. I think we all have a good sense of what’s going well (American women), what’s going not so well (American men) and what’s going OK (Canadian men, given their expectations). But it’s always nice to have some numbers.

Women’s Distance

Keep in mind that the number of results per race thus far this season is based on a smaller set of races since the season isn’t complete.

As we all know, the American women are having a banner year. In two seasons they’ve gone from landing someone in the top 30 around around half the time to consistently putting two women in the top thirty, often three. Read more

How will Jessie Diggins fare on the World Cup?

The only sure way to know, of course, is to wait a few weeks and see what happens when she gets to Europe. But there’s been some commentary from the peanut gallery about how dominant Diggins has been on the domestic circuit so far.

This is one of those problems that FIS points are supposed to solve, but no sane person actually believes that they do. In an ideal world, you could simply look at the FIS points for Diggins’ domestic races and compare them directly to the World Cup field. But we all know that doesn’t work so well.

My preferred method for making comparisons like this is to isolate comparisons between specific groups of skiers when they race against each other head to head. In this instance, I’d like to compare Diggins to the other three top American women Randall, Brooks and Stephen. If we took Diggins’ results and transfered them to the World Cup, how would they compare to the strong races these three ladies have had?

For the cleanest comparison possible, we’ll restrict ourselves only to interval start distance races. What I’ve done is a little hard to explain clearly, even though it’s fairly simple. here’s the deal:

  • Take all the domestic interval start distance races that Diggins has done so far and identify the top ten women in each race. Let’s call them Diggins’ Opponents. Diggins has been (mostly) beating them soundly. Calculate the difference in FIS points between Diggins and Diggins’ Opponents.
  • Now consider all the times that Randall, Brooks and Stephen skied against Diggins’ Opponents (last season, of course, in interval start distance races). Calculate the FIS point difference between each of these three and DIggin’s Opponents
  • Now we can compare Diggins, Randall, Brooks and Stephen against each other, using Diggins’ Opponents as a common reference.

 

This graph shows the median and middle 50% of those differences for each skier. Negative values indicate that skier did better than Diggins’ Opponents.

Not surprisingly, Randall tended to fare the best. The degree to which Diggins has “crushed” the domestic field so far this season falls somewhere in between Brooks and Stephen, but definitely a bit behind Randall. I think this is fairly strong evidence that Diggins may very well be skiing no worse than Liz Stephen right now, which would easily plant her in the top 30.

There are two big caveats. First, I think you’d have to subtract a bit given that she’s less acclimated to the travel and general commotion of the WC scene, but you never know. Second, it’s entirely plausible that at least Randall and Brooks (and possibly Stephen) are skiing considerably better now than they were last season. Since they’ve been in Europe so far this season, they haven’t raced against Diggins’ Opponents yet this year, so I only have last years races to go on.

The end result here is that I wouldn’t be surprised at all to see Diggins in the 30’s. Between 20-30 would be an excellent day, but not shocking. And anything in the 15th or better zone would be approaching “race of her life” (thus far) territory.

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