Category: XCFeeds

a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCU0K-haByI/AAAAAAAADEA/xo1Et8w_OCo/s1600/IMG_4821.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCU0K-haByI/AAAAAAAADEA/xo1Et8w_OCo/s400/IMG_4821.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486849084207269666″ //aWe had a fun filled day at our camp. After a fine breakfast, we headed to Pineland Farms for a trail run and some plyo’s and bounding. We then went to the ocean and kayaked around Little John island. Everyone was a bit sore from yesterdays specific strength workout, but it was a fun paddle that took about an hour.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCUzxComktI/AAAAAAAADD4/nRu18dnz1sU/s1600/IMG_4822.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCUzxComktI/AAAAAAAADD4/nRu18dnz1sU/s400/IMG_4822.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486848638634595026″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCUzST4oH9I/AAAAAAAADDw/Hur8XkZPgrk/s1600/IMG_4827.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCUzST4oH9I/AAAAAAAADDw/Hur8XkZPgrk/s400/IMG_4827.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486848110689263570″ //aHallie and Tess took to the boat like a couple of old pros.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCUyy8LUrwI/AAAAAAAADDo/xpWZVc4Euiw/s1600/IMG_4839.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCUyy8LUrwI/AAAAAAAADDo/xpWZVc4Euiw/s400/IMG_4839.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486847571749285634″ //aCam and Issy P showing good form.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCUyKyR6dYI/AAAAAAAADDg/wFaJufbJziA/s1600/IMG_4844.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCUyKyR6dYI/AAAAAAAADDg/wFaJufbJziA/s400/IMG_4844.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486846881897805186″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCUxtIKPhgI/AAAAAAAADDY/NO1i5jFWh0Q/s1600/IMG_4851.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCUxtIKPhgI/AAAAAAAADDY/NO1i5jFWh0Q/s400/IMG_4851.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486846372375135746″ //aNick and Tyler.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCUxLMmOI6I/AAAAAAAADDQ/I5XHJ2OOAPA/s1600/IMG_4856.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCUxLMmOI6I/AAAAAAAADDQ/I5XHJ2OOAPA/s400/IMG_4856.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486845789450675106″ //aBrrrrr….br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCUwpJ4nmPI/AAAAAAAADDI/zbPaYxGy3vY/s1600/IMG_4859.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCUwpJ4nmPI/AAAAAAAADDI/zbPaYxGy3vY/s400/IMG_4859.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486845204606982386″ //aCoach Boobar and Tyler discuss the art of skim boarding while the girls chat about the cold water.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://4.bp.blogspot.com/_H2SCM3lmKm8/TCUwOKwg1qI/AAAAAAAADDA/yx5upqvsZFY/s1600/IMG_4868.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://4.bp.blogspot.com/_H2SCM3lmKm8/TCUwOKwg1qI/AAAAAAAADDA/yx5upqvsZFY/s400/IMG_4868.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486844740984952482″ //aAfter a late lunch we headed out for some skate roller ski technique work and a little beach time :)br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCUvq0sGBWI/AAAAAAAADC4/HXE8SB9u8iE/s1600/IMG_4865.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCUvq0sGBWI/AAAAAAAADC4/HXE8SB9u8iE/s400/IMG_4865.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486844133765416290″ //aCam heads out for some surfing and Hallie hits the skim board.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://4.bp.blogspot.com/_H2SCM3lmKm8/TCUu_ql2idI/AAAAAAAADCw/1JaTSfCYkBc/s1600/IMG_4867.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://4.bp.blogspot.com/_H2SCM3lmKm8/TCUu_ql2idI/AAAAAAAADCw/1JaTSfCYkBc/s400/IMG_4867.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486843392320506322″ //aAll bark and no bite.br /We are now sitting down to a great dinner and plan to hit the hay early.div class=”blogger-post-footer”img width=’1′ height=’1′ src=’https://blogger.googleusercontent.com/tracker/4680416899705879324-2315175572819687824?l=smsxc.blogspot.com’ alt=” //div

The Statistical Wife and I are getting pumped for the USA-Ghana game tomorrow.  Whatever World Cup team you’re partial to (after the USA, I confess to having a soft spot for Holland), here’s a recap of what’s been going on here at Statistical Skier this week.  A little light reading between soccer games, perhaps…

• I explained why F-factors are such a terrible solution to the problem of FIS point discrepancies between interval and mass start races and provided a better one myself.  (Anyone from FIS reading this?)
• The results of my reader poll came in and you chose to see how Bjoern Daehlie fared against Thomas Alsgaard, head-to-head.  If you voted for someone else, don’t worry!  This will be a regular feature…
• After reading short report from Nat Herz at Fasterskier.com about biathlete Tim Burke’s offseason training plans, I delved into his career skiing and shooting stats a bit.
• The skier retirement article series continued with Canadian Sara Renner.
• Finally, upon the request of a commenter, I followed up on my doping post from last week with a quick update.

Have a great weekend!

Last week I looked at the distance race results of some skiers who had been caught using performance enhancing drugs.  A commenter wondered if I could show some data for “suspected dopers” as well.

Honestly, I was a bit reluctant to do that.  I mean, as much as I hate doping, the negative consequences of being labelled one are enough that I think we should be pretty careful about throwing accusations around, particularly in public.

In the end, though, I think we can do this responsibly by being very careful to remember that the only certain way to catch dopers is in the act (and even then it can get ambiguous).  I sort of hope that this exercise will reinforce the lesson from my last doping post that looking for evidence of funny business using graphs of race results is highly unreliable.

Along with my commenter’s suggestions of Andrus Veerpalu and Christian Hoffman, Kristina Smigun-Vaehi and Mikhail Botvinov were suggested to me as skiers who might be considered “suspicious” within the skiing community.

Here are their distance results:

As before, I’ve highlighted sections of careers that might conceivably be considered suspicious.  Botvinov had been racing since 1990, so I’m actually only missing 1-2 seasons from him.  He appeared to have been slowing down somewhat until making a modest improvement in 1995-1996.  Then he defected to Austria and had to sit out several seasons until his citizenship issues were worked out.  When he started skiing again, he was quite a bit faster.

Smigun-Vaehi appears to have made a big jump between the 1997-1998 and 1998-1999 seasons.  The gap later in her career came when she had a child and took some time off.

Veerpalu and Hoffmann on the other hand don’t have anything that particularly stands out, at least to my eye.  I suppose Hoffmann got fast pretty quick, but we don’t have much of a record prior to 1996 for him, so it’s hard to read much into that.

In the end, I don’t think we learn much from these kinds of things.  It’s easy to look back at people we know cheated and find little things that seem suspicious.  But as I’ve said before, you can’t just assume that people who make big jumps are doping.  Sometimes people just get faster.  There are tons of skiers who’ve made big “suspicious” looking jumps who no one would think is doping.

In these particular cases, Botvinov and Hoffman actually came awfully close to being “officially” caught in 2002 but were eventually cleared by the IOC.  In any case, I sure as hellam not going to call one of my little graphs anything close to “evidence” for doping.

Next up in our retiring skier series is Sara Renner.  Renner (CAN) retired this past season after competing internationally for around 16 years.  She earned a Gold Silver medal at the Turin games in the Team Sprint event with Beckie Scott, but wasn’t quite as fortunate in individual events. (Update: Sorry for the typo!)

However, along with Beckie Scott and Kikkan Randall, Renner has been among the best North American women competing on the World Cup circuit in recent history.  She’s managed 5 podium finishes, including a third place in the sprint race at World Championships in 2005.  Her best distance race probably was a 2nd place finish at the 10k classic World Cup race in Davos in 2006.

Let’s take a look at all of her distance results:

Sara Renner's distance results.

We see a small number of races prior to 2000 and then a huge jump between 2000 and 2001.  After that, she remained fairly consistent (at least in terms of her “average” race) but her best results each season improved fairly steadily through 2006.

That season was easily Renner’s best overall.  The Tour de Ski (TDS) result in 2010 that looks very fast is slightly deceptive.  That was a 10k mass start classic race that we’ve discussed before that resulted in an extremely bunched finish.  Renner got around 5 FIS points for a 14th place finish that day.  I suspect the stage race format of the TDS played a significant role in race tactics that day.

After taking a year off following the Turin Olympics, Renner’s average results have remained roughly steady, but her best races have tailed off somewhat.  One notable exception is the World Cup race in Feb 2009 where she finished 5th (another 10k classic race).

Did she have a preference for skating or classic?

Sara Renner's distance results by technique.

The trend lines suggest only a slight edge for classic skiing here, but I think that might be understating the difference slightly.  With the exception of some pursuits (FC or green dots) Renner’s best races seem to trend towards classic events.

Now let’s see if she had any strong preferences for races of different lengths:

Sara Renner's distance results by length.

It’s not overwhelming, but I’d tend to call that a preference for shorter races.  She didn’t do a ton of 30k’s, but when she did, they weren’t often her best races.  This might suggest, along with her Gold Silver medal in the team sprint, that she was more of a sprint specialist.  Let’s check out her sprint results…

Sara Renner's sprint results.

From 2002 to 2006 she was a fairly regular top 10 finisher in World Cup sprints, and virtually always qualified for the elimination rounds (top 30).  Like her distance skiing, her sprint results have generally tailed off somewhat over the past few seasons, though she managed to put a good race together at the Canadian World Cups just prior to the Olympics this past season.  Let’s look to see if she also had a preference for classic in sprint races…

Sara Renner's sprint results by technique. y-axis label should be Rank not FIS Points.

Somewhat surprisingly, I’d say the answer is no.  Her best sprint races are pretty much evenly split between classic and freestyle.

So long, Sara, and good luck!

a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCP2ScuX6cI/AAAAAAAADCo/N_jqVPwM5dA/s1600/IMG_4809.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 239px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCP2ScuX6cI/AAAAAAAADCo/N_jqVPwM5dA/s400/IMG_4809.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486499567876172226″ //aThis is our first training camp weekend of the summer. We have 7 current students plus 5 alums at the Regional Elite Camp in Craftsbury and 7 more kids who have ventured to the Halls house in Maine for a 4 day camp. We are running the Maine camp at the same time to keep everyone on the same basic schedule and to give everyone a concentrated period of coaching.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCP120h1-EI/AAAAAAAADCg/pEpE8EYsPRY/s1600/IMG_4811.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 246px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCP120h1-EI/AAAAAAAADCg/pEpE8EYsPRY/s400/IMG_4811.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486499093229729858″ //aThis afternoon we did a specific strength workout. 1:30-1:45 of d-pole and single pole with a couple of technique drills thrown in. The roads here are smooth and gentle so it is great for easy roller skiing. We had a little rain at the start of our ski, but then it cleared up and was quite nice.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCP0UTxc6bI/AAAAAAAADCY/6UApTFDiC98/s1600/IMG_4817.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCP0UTxc6bI/AAAAAAAADCY/6UApTFDiC98/s400/IMG_4817.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486497400809646514″ //aWe headed down to Portland for a fine dinner of flatbread pizza. Here are some of the kids on “the docks”. We hoped to see alum Jordi St. John heading out on his charter sailboat, but no luck tonight.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCPzlt63zUI/AAAAAAAADCQ/yiX3eOtG1hg/s1600/IMG_4819.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 234px;” src=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCPzlt63zUI/AAAAAAAADCQ/yiX3eOtG1hg/s400/IMG_4819.JPG” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486496600374627650″ //aTyler is doing his best to fend off Cam and Issy P.div class=”blogger-post-footer”img width=’1′ height=’1′ src=’https://blogger.googleusercontent.com/tracker/4680416899705879324-6998741106005831736?l=smsxc.blogspot.com’ alt=” //div

I just finished reading a great article checking in with US biathlete Tim Burke as he gears up again for next season.  I was vaguely aware that Burke had a great season last year but a disappointing Olympics, but I don’t follow biathlon as closely as cross country.  So I thought I’d check some data and educate myself a bit.

Here’s what I’ve got of Tim Burke’s career so far:

I calculated the percent back values myself, since biathlon doesn’t use a point system like FIS does in cross country.  Burke had been a decent skier for about three season and then clearly made a jump last year.  It’s also clear how much he struggled at the Olympics.  His one decent Olympic race at Vancouver was really just an average race for him over the whole season.

Burke also mentioned that apparently he has struggled with his standing shooting and so is focusing on that during the offseason.  With that in mind, let’s look at Burke’s shooting:

The solid lines represent Burke and the dotted lines represent male top 10 finishers over the same time period, for reference.  This paints a pretty clear picture.  If Burke improved his standing accuracy by 5-10 percentage points he’d likely make another big jump next season.  Indeed, that would probably make him regular podium finisher.  I have no idea if that sort of improvement is feasible (intuitively, it seems like a big jump to me for one off-season), but it’d be awesome to see.

June 23rd is Olympic Day in celebration of the birth of the modern Olympics.  The LCO Boys and Girls Club celebrated the day with 2010 Olympian Garrott Kuzzy and several members of CXC Team Vertical Limit.

Getting Fired up watching highlights from the 2010 Games

Santi cheering Delilah on in the Pineapple Slalom

Ardepol Puppin.

One of the most challenging legs of the relay was Ardepol Puppin.   I am nearly positive I am spelling it wrong, but one of the funniest and most challenging games was Ardepol Pupping.  Everyone had to set a potato on a chair, sit down and pick it up, waddle over and drop it in a bowl.  This was a fun one to watch.

Running the Jump Rope Gauntlet

Potatoes make you strong

Refueling our hardwork with fresh Pineapple. 90% of the kids were enjoying fresh pineapple for the first time

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a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_Qy8LpbgYOag/TCLviFaeUlI/AAAAAAAAAWA/-GvI_za5Fk0/s1600/post+camp+poster.jpg”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 267px; height: 400px;” src=”http://3.bp.blogspot.com/_Qy8LpbgYOag/TCLviFaeUlI/AAAAAAAAAWA/-GvI_za5Fk0/s400/post+camp+poster.jpg” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486210664938492498″ //abr /br /The Fire and Ice Ski Camp on the trails of Mt. Bachelor has come to an end. With it, so has the last day of groomed skiing here in Bend. Putting on the camp was a bit of work, but the skiers, from young to old, were super stoked so this made it all worth it.br /br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://1.bp.blogspot.com/_Qy8LpbgYOag/TCLvjUL7eeI/AAAAAAAAAWI/UDIIb4mpl60/s1600/torin+and+annika.jpg”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 300px; height: 400px;” src=”http://1.bp.blogspot.com/_Qy8LpbgYOag/TCLvjUL7eeI/AAAAAAAAAWI/UDIIb4mpl60/s400/torin+and+annika.jpg” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486210686083889634″ //abr /br /Annika and a big crew from one of my old haunts, the big city streets of Salt Lake City, came out west for the camp. If you knew that some of the U.S.’s best up and coming nordic skiers might come from the downtown SLC West High School you too might be impressed. br /br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_Qy8LpbgYOag/TCLvjzyHksI/AAAAAAAAAWQ/9ldefCey02E/s1600/crew+at+bachey.jpg”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 267px;” src=”http://3.bp.blogspot.com/_Qy8LpbgYOag/TCLvjzyHksI/AAAAAAAAAWQ/9ldefCey02E/s400/crew+at+bachey.jpg” border=”0″ alt=””id=”BLOGGER_PHOTO_ID_5486210694565565122″ //abr /br /The campers posing with the alpine slopes of Mt. Bachelor as a backdrop. Finally, the warm sunny days of summer seem to making more than just a cameo appearance out here in the west.div class=”blogger-post-footer”img width=’1′ height=’1′ src=’https://blogger.googleusercontent.com/tracker/2691525267872963085-6489755884368866875?l=in-the-arena-torin.blogspot.com’ alt=” //div

Previously, I described some problems with using percent back (PB) as a basis for comparing race performances.  Namely, mass start and interval start races produce very different types of PB’s.  In this post we’ll briefly consider whether this problem is actually worth worrying about and then I’ll finish with a simple solution.

At first glance, the discrepancy between mass and interval start races seems awfully dramatic, and it is.  However, there is some reason to think that we shouldn’t worry about it, at least in some specific circumstances.

This discrepancy will only produce systematic advantages for some athletes over others if the skiers are choosing to race only mass or interval start races.  If everyone has the same opportunity to ski in races that lead to better PB’s, we might not need to worry.  Specifically, for the purposes of averaging large numbers of results from multiple races and then using these averages to rank athletes, we shouldn’t worry.

This argument only works well where you have a relatively stable set of athletes competing week in and week out.  To some extent, this is true on the World Cup circuit, at least for the top skiers.  There is quite a bit of churn at the bottom I imagine.  Keep in mind, though, that slower athletes will tend to have their FIS points inflated by the current rules if they do a mass start race, so it might actually be advantageous for these skiers to pick interval start races if they’re only getting a handful of starts.

What does break down is the ability to compare two isolated results, either for a single athlete or between two different athletes.

These are subtle differences, so I’m going to summarize them as clearly as I can: differences between mass and interval start races probably have

• limited impact on relative measures of athlete performance using averages from many different races (assuming everyone is doing roughly the same number of mass and interval start races).  If you’re averaging multiple FIS point results to compare athletes, nations etc., you’re probably ok.
• a significant impact on our ability to compare two particular results from specific races.  If you take two specific results from different races, we may have a difficult time interpreting which represents a “better” result.

Finally, there is the question of what sort of impact this has on comparing FIS points between international and domestic races.  This leads us into territory I want to avoid, as it raises the issue of whether race penalties accurately capture the strength of a field.  I’ll leave that question for another day.

Now, assuming we want to fix this problem, can we think of something better than F-factors?  If you’ve ever gone to school, in almost any capacity, you’ve probably encountered the most obvious solutions: grading on a curve.

The procedure is simple.  We pick a reference distribution that we’d like to peg our results to.  We can choose anything we want.  In grading, usually people pick a bell curve.  That doesn’t make much sense in this case.  Instead, we can simply use the distribution of interval start PB’s.  I don’t even really need to check whether the resulting distributions will be the same, because, by definition, what I’ve done is to make them the same.

Here’s the sequence of steps in gory detail:

1. Convert a mass start PB to a percentile (i.e. it’s better than 98% of all mass start PB’s)
2. Find the equivalent percentile for interval start races (i.e. 98% of interval start PB’s are above, say, 0.015)
3. This is my converted PB value: 0.015!

That’s it.  I said I don’t even need to check whether the resulting distributions are the same, but in case you don’t believe me:

You can just barely make out the red interval start line peaking out from behind the mass start line.  Like I said, this procedure, by definition, creates identical distributions of PB’s.  Now to convert these PB’s to what we’re familiar with as FIS points we can simply multiply them all by 800.  Easy as pie.

Since I’m a baseball fan, I’ll use a fancy sounding Sabermetric-ish acronym for this EqPB (Equivalent Percent Back).

The next interesting thing to do is to look at the results for particular athletes, or groups of athletes and see if using EqPB causes any big changes to see if I was right about when we should and should not worry about these differences…

The poll on the right is now closed.  Marit vs Justyna was in the running for a while, but Daehlie vs Alsgaard eventually pulled away for a clear win.

Don’t worry if the matchup you voted for didn’t win this time around, we’ll have another round of voting most likely in a few days.

The head-to-head matchup for Daehlie and Alsgaard is below the fold…

Bjoern Daehlie and Thomas Alsgaard gave us a wonderful rivalry of sorts during the 90′s.  Let’s visualize it!

I took the 61 races I could find in which Daehlie and Alsgaard raced against each other, and simply subtracted their FIS points (Daehlie – Alsgaard).  This means that negative values represent times when Daehlie beat Alsgaard and vice versa.  Here’s a simple graph with the results:

The FC technique refers to pursuit races, which at the time were all pursuits with a break (classic race, followed by skate pursuit).  So those races are actually a mix of classic and freestyle.

As we might have guessed, Daehlie had the better of this matchup: nearly all these points are below zero.  Alsgaard’s strength in skating is clearly visible when comparing the two trend lines I added for freestyle and classic races. (I skipped doing a trend line for pursuit, or FC, races.)  Alsgaard seemed to compare more favorably to Daehlie in 1994 (Alsgaard’s break though results at the Lillehamer Olympics) and then later toward the end of Daehlie’s career.  During 1995 and 1996, Daehlie was pretty tough to beat.

As with any dataset, we should at least comment on any unusual looking data.  I count three odd looking races.  Two very large victories by Daehlie and one by Alsgaard.  The lopsided Alsgaard victory came in Feb 1995 at the 50k classic in Oslo.  Daehlie was 48th.  This first lopsided Daehlie victory was actually the 10km classic race at the Lillehammer Olympics.  Alsgaard was 24th, nearly 2 minutes behind Daehlie, who won.  The second was in Nov 1996, an early season 10km freestyle World Cup race in Kiruna, Sweden.  Alsgaard was 61st.  (American skier Marcus Nash was 28th that day, ~45 seconds ahead of Alsgaard.)

Just for fun, we can look at the pursuit races to see how much ground Alsgaard gained (or lost) during the freestyle half of the pursuit.  The bumps plot below shows the changes in the difference in FIS points from the classic race to the overall result of the pursuit.  Lines sloping upward represent Alsgaard closing the gap, and vice versa.  The blue lines are races where Daehlie won the classic portion of the pursuit, red lines are races where he did not.

Obviously, this isn’t necessarily evidence that Alsgaard was a stronger skater.  Daehlie won the classic portion of half (4) of these pursuits, which will likely influence his strategy in the skating portion.  Namely, from Daehlie’s perspective, he only needs to ski faster than the guy behind him.  So we won’t much care if other people further back are gaining ground.  On the other hand, in each case Alsgaard closed the gap significantly three of the four times.

Tilly Gregg

When I was in 4th grade I remember coming home from soccer practice and Mom and Dad told the three of us kids there was a big surprise waiting for us in the garage.   We opened the door and the cutest dog ever ran out into the yard.

We named her Tilly after the pacific northwest Tillicum Tribe.  She gets reminded off her namesake when we call her.

The Gregg's at Glacier Peak: Jim, Chad, Brian, Tilly, Tara, Jan

After nearly 16 years of fun and adventures Tilly took her final nap the other day. It is sad to lose such a good and faithful friend.  Still, I can’t help but smile as I flip through pictures and recall the many good memories we have made together.  We have always done things as a family and Tilly is part of the family. Living in Baja, Mexico for a month while she was a puppy, flying on the airplane as an avalanche ‘service’ dog, spring crust skis, camping, back country tours, runs/hikes in the mountains and even a bit of rock climbing.

Farm Dog:

She always entertained us and we would try to do the same.  One year we got some runner ducks (think Aflak commercial) to herd, that didn’t work as well as the sheep.  She enjoyed working in the yard and hanging out under the grease drip of ‘Old White’

Where are my skis?

a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://4.bp.blogspot.com/_H2SCM3lmKm8/TCEMB9NlkRI/AAAAAAAADCI/Os4QbG2-YHY/s1600/IMG_4674.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://4.bp.blogspot.com/_H2SCM3lmKm8/TCEMB9NlkRI/AAAAAAAADCI/Os4QbG2-YHY/s400/IMG_4674.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485679048864928018″ //aWe skied classic hill intervals today at school. This was also the first day for our young “Devo” program. We had a great group with 18 regulars and 13 Devo kids.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCELzGVhhsI/AAAAAAAADCA/XHsoEU0QKrQ/s1600/IMG_4678.JPG”img style=”float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCELzGVhhsI/AAAAAAAADCA/XHsoEU0QKrQ/s320/IMG_4678.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485678793616099010″ //aEveryone started with some technique drills.divbr //divdivCheck out the Video at the bottom of the page.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCELlEgOA_I/AAAAAAAADB4/wIFiFie6i3Y/s1600/IMG_4687.JPG”img style=”float:right; margin:0 0 10px 10px;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCELlEgOA_I/AAAAAAAADB4/wIFiFie6i3Y/s320/IMG_4687.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485678552605918194″ //aPictures are smaller today, but you can click on any to enlarge.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCELZEW3tJI/AAAAAAAADBw/T-7AI80A_Po/s1600/IMG_4689.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCELZEW3tJI/AAAAAAAADBw/T-7AI80A_Po/s320/IMG_4689.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485678346408277138″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCELNUcy6SI/AAAAAAAADBo/Muj2H0V_URQ/s1600/IMG_4692.JPG”img style=”float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCELNUcy6SI/AAAAAAAADBo/Muj2H0V_URQ/s320/IMG_4692.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485678144569665826″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCELBC8ih6I/AAAAAAAADBg/lR3ZK38HB5g/s1600/IMG_4698.JPG”img style=”float:right; margin:0 0 10px 10px;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCELBC8ih6I/AAAAAAAADBg/lR3ZK38HB5g/s320/IMG_4698.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485677933712541602″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEKg81bbKI/AAAAAAAADBY/dEKTkX6dQIc/s1600/IMG_4706.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEKg81bbKI/AAAAAAAADBY/dEKTkX6dQIc/s400/IMG_4706.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485677382316289186″ //a”Give back time”. The older kids helped the Devo kids with their d-pole technique as part of the warm up for the workout.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCEKS3Hci0I/AAAAAAAADBQ/ZRignLkCPBQ/s1600/IMG_4723.JPG”img style=”float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCEKS3Hci0I/AAAAAAAADBQ/ZRignLkCPBQ/s320/IMG_4723.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485677140263078722″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEKF5Wr4ZI/AAAAAAAADBI/t1oEIRA5YG8/s1600/IMG_4724.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEKF5Wr4ZI/AAAAAAAADBI/t1oEIRA5YG8/s320/IMG_4724.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485676917525569938″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://4.bp.blogspot.com/_H2SCM3lmKm8/TCEJ5fi73lI/AAAAAAAADA8/Z-LUjRc3XrM/s1600/IMG_4726.JPG”img style=”float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://4.bp.blogspot.com/_H2SCM3lmKm8/TCEJ5fi73lI/AAAAAAAADA8/Z-LUjRc3XrM/s320/IMG_4726.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485676704439197266″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCEJT8HGxAI/AAAAAAAADA0/VLDpPMdyvdM/s1600/IMG_4739.JPG”img style=”float:right; margin:0 0 10px 10px;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCEJT8HGxAI/AAAAAAAADA0/VLDpPMdyvdM/s320/IMG_4739.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485676059272070146″ //aWe have a great hill next to school, It is about 3 kms of steep up. Here are the boys doing the first of their 6 X 1 km intervals.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEI4P8aezI/AAAAAAAADAs/dCPod7ck-yM/s1600/IMG_4740.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 400px; height: 300px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEI4P8aezI/AAAAAAAADAs/dCPod7ck-yM/s400/IMG_4740.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485675583559596850″ //aSophie just returned from a “great” NTG camp in Park City. Here she is leading some of the SMS girls during an interval.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCEIuO8XltI/AAAAAAAADAk/51P9s2Q7YOU/s1600/IMG_4742.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCEIuO8XltI/AAAAAAAADAk/51P9s2Q7YOU/s320/IMG_4742.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485675411492280018″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEIhMcGJ7I/AAAAAAAADAc/fZAtdRxhH6w/s1600/IMG_4747.JPG”img style=”float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEIhMcGJ7I/AAAAAAAADAc/fZAtdRxhH6w/s320/IMG_4747.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485675187481749426″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEIVT31-zI/AAAAAAAADAU/8JqCDqypIKA/s1600/IMG_4753.JPG”img style=”float:right; margin:0 0 10px 10px;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEIVT31-zI/AAAAAAAADAU/8JqCDqypIKA/s320/IMG_4753.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485674983318747954″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCEH8wlY5RI/AAAAAAAADAM/tiP1NI2CZhE/s1600/IMG_4768.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCEH8wlY5RI/AAAAAAAADAM/tiP1NI2CZhE/s320/IMG_4768.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485674561529242898″ //aAfter their technique work, the devo kids skied the top half of the uphill and watched the older kids finish their intervals.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCEHxElNgAI/AAAAAAAADAE/vRh43ZSBfDM/s1600/IMG_4771.JPG”img style=”float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://1.bp.blogspot.com/_H2SCM3lmKm8/TCEHxElNgAI/AAAAAAAADAE/vRh43ZSBfDM/s320/IMG_4771.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485674360738775042″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCEHmbLmRgI/AAAAAAAAC_8/ZaiHPRAsJdw/s1600/IMG_4773.JPG”img style=”float:right; margin:0 0 10px 10px;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCEHmbLmRgI/AAAAAAAAC_8/ZaiHPRAsJdw/s320/IMG_4773.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485674177826801154″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEHZTrxFnI/AAAAAAAAC_0/pIXvJ_ORjng/s1600/IMG_4776.JPG”img style=”display:block; margin:0px auto 10px; text-align:center;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEHZTrxFnI/AAAAAAAAC_0/pIXvJ_ORjng/s320/IMG_4776.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485673952475944562″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCEHCZdSqFI/AAAAAAAAC_s/y598qIUZFjM/s1600/IMG_4780.JPG”img style=”float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://3.bp.blogspot.com/_H2SCM3lmKm8/TCEHCZdSqFI/AAAAAAAAC_s/y598qIUZFjM/s320/IMG_4780.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485673558888851538″ //aDoug double poled the whole thing twice.br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://4.bp.blogspot.com/_H2SCM3lmKm8/TCEGvgumOzI/AAAAAAAAC_k/4oHMhUomkI0/s1600/IMG_4783.JPG”img style=”float:right; margin:0 0 10px 10px;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://4.bp.blogspot.com/_H2SCM3lmKm8/TCEGvgumOzI/AAAAAAAAC_k/4oHMhUomkI0/s320/IMG_4783.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485673234422971186″ //aLast interval!br /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEGiHkWwrI/AAAAAAAAC_c/bAdRQp78hXQ/s1600/IMG_4789.JPG”img style=”float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://2.bp.blogspot.com/_H2SCM3lmKm8/TCEGiHkWwrI/AAAAAAAAC_c/bAdRQp78hXQ/s320/IMG_4789.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485673004330828466″ //abr /a onblur=”try {parent.deselectBloggerImageGracefully();} catch(e) {}” href=”http://4.bp.blogspot.com/_H2SCM3lmKm8/TCEGB4CdERI/AAAAAAAAC_M/I_GZLurck3o/s1600/IMG_4795.JPG”img style=”float:right; margin:0 0 10px 10px;cursor:pointer; cursor:hand;width: 320px; height: 240px;” src=”http://4.bp.blogspot.com/_H2SCM3lmKm8/TCEGB4CdERI/AAAAAAAAC_M/I_GZLurck3o/s320/IMG_4795.JPG” border=”0″ alt=”” id=”BLOGGER_PHOTO_ID_5485672450406289682″ //aobject width=”320″ height=”266″ class=”BLOG_video_class” id=”BLOG_video-19e684c7bb9d897″ classid=”clsid:D27CDB6E-AE6D-11cf-96B8-444553540000″ codebase=”http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,40,0″param name=”movie” value=”http://www.youtube.com/get_player”param name=”bgcolor” value=”#FFFFFF”param name=”allowfullscreen” value=”true”param name=”flashvars” value=”flvurl=http%3A%2F%2Fv3.nonxt3.googlevideo.com%2Fvideoplayback%3Fid%3D019e684c7bb9d897%26itag%3D5%26app%3Dblogger%26ip%3D0.0.0.0%26ipbits%3D0%26expire%3D1282311139%26sparams%3Did%252Citag%252Cip%252Cipbits%252Cexpire%26signature%3D23EE2D35BB910CB05E9AE401D6A421740A7E4765.179DF8806C7D762508856F1D3715B385EC23D9DD%26key%3Dck1amp;iurl=http%3A%2F%2Fvideo.google.com%2FThumbnailServer2%3Fapp%3Dblogger%26contentid%3D19e684c7bb9d897%26offsetms%3D5000%26itag%3Dw320%26sigh%3Dc1P9WvVnAGit03nlEhhtl_Z4pTYamp;autoplay=0amp;ps=blogger”embed src=”http://www.youtube.com/get_player”width=”320″ height=”266″ bgcolor=”#FFFFFF”flashvars=”flvurl=http%3A%2F%2Fv3.nonxt3.googlevideo.com%2Fvideoplayback%3Fid%3D019e684c7bb9d897%26itag%3D5%26app%3Dblogger%26ip%3D0.0.0.0%26ipbits%3D0%26expire%3D1282311139%26sparams%3Did%252Citag%252Cip%252Cipbits%252Cexpire%26signature%3D23EE2D35BB910CB05E9AE401D6A421740A7E4765.179DF8806C7D762508856F1D3715B385EC23D9DD%26key%3Dck1iurl=http%3A%2F%2Fvideo.google.com%2FThumbnailServer2%3Fapp%3Dblogger%26contentid%3D19e684c7bb9d897%26offsetms%3D5000%26itag%3Dw320%26sigh%3Dc1P9WvVnAGit03nlEhhtl_Z4pTYautoplay=0ps=blogger”allowFullScreen=”true” //object/divdiv class=”blogger-post-footer”img width=’1′ height=’1′ src=’https://blogger.googleusercontent.com/tracker/4680416899705879324-3808199508229047479?l=smsxc.blogspot.com’ alt=” //div