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Just Bill
07-12-2013, 16:26
In researching the trail in general, and speed records in particular I have been working hard to sort out the "hard/easy" debate. I realize this is only on paper. We all have bad days, bad weather, and even amazing days. It is unfair to call anything on the trail average. That said, data is data, and map man has done some pretty amazing things. I just got Jen's latest book and was updating my sheets regarding her data and I got the idea for this sheet. I am no mathematician by any means- so for those that are good at this sort of thing; Are my assumptions correct- and is this a fair way to work out a statistical average for MHPD? If so, does the rest of the sheet make sense? If not- can you take the idea and run with it? The main goal- if you didn't need time to build trail legs- is this a reasonable weighted average?22666

Odd Man Out
07-12-2013, 16:58
It looks as if the row labeled "weighted average" is an average of the number in the column above. This ignores the fact that these segments are not all exactly the same length. What you should do is have a column labeled "Miles" that lists the miles for each segment. Then insert a column next to each of the different target hiking speeds labeled "Days". Use the formula miles/MPD to calculate the days it would take to hike each segment. For example in the first row under "Miles" will be 188.2 (the miles from Katahdin to Stratton as per http://www.atdist.com/atdist ) . Then the first number in the "Days" column to the right of "15 MPD" will be 9.73 which is the days it will take to hike this segment (188.2 divided by 19.34). Then you just add up the "Days" column to get the Days to Complete value. To get a true average hiking speed, just divide the total distance (2185.9 miles) by the total days.

I will let other debate the accuracy of weighting hiking speeds on ratios of hardest to easiest segment.

Using the higher number based on the assumption you start in hiking shape seems reasonable.

Just Bill
07-12-2013, 17:41
22668Thanks Odd Man Out- here is an updated version with your suggestion, the numbers are different, but not by much (unless I'm missing something map man's numbers were already averaged?) I agree about not having the debate- it's data, not real life. You would know better than I, but the 25MPD also looks fairly comparable to Matt's current pace and your sheet. (the 30mpd projection isn't far off of JPD time either) It isn't an end all set of data, but I have had a hard time trying to balance two issues- 1- everyone (rightly so) has a different opinion on each section- but for planning you have to take some kind of intelligent stab at it. 2- I'm not Mr. Leonard, I won't have the chance to be on trail as much as he was, so I have to extrapolate some sort of expectations based upon my recent tune-up trip and future tune-ups. Basically to answer the question-when doing a section- Am I on track?

Just Bill
07-12-2013, 18:33
Just for fun- using whole days only from Odd Man Out's summary of Matt's Attempt.22672

Just Bill
07-12-2013, 18:41
Okay- let's get stupid- green days are hard numbers for Matt, Yellow are projections based upon the sheet. Go Matt Go!22673

Just Bill
07-12-2013, 23:06
22682Sorry for the impulsive posts, I'm a hair exited though- this "formula" matches up pretty well (+/- 3%) to Jennifer Pharr Davis's record times. I'm not saying anything, it's only a sample of one but...interesting at least for my fellow spreadsheet nerds. I couldn't match it perfectly as I only have her daily splits and nothing more detailed, but they match map man's breakdown pretty close as is. Her last day (half day) probably skews the numbers a hair as she was on a much faster pace (148.6/2.5=59.44 MPD). Last one I promise! Odd Man- I finally understood your original point (I think)- because Map Man's numbers are averages you need to convert them the way you suggested to match the current year's mileage to have an up to date projection? Hence the minor variation. (Didn't click until I tallied up Jen's total miles.)

Colter
07-14-2013, 11:07
Very interesting numbers Just Bill. Thanks!

map man
07-14-2013, 21:19
Looking at Just Bill's table in post #6 and noting how many hiking days it took Jen Pharr Davis and the "average" SOBO successful thru-hiker to complete the various sections, it is spooky how close the ratios are for each segment. It took just slightly less than three times as many hiking days for the average hiker to complete each section compared to JPD. And this holds up for section after section. That does seem a bit counter-intuitive -- I would have expected an elite hiker, already in great shape, not to match up so closely (considering the ratios) in the early days of the hike to the more common hikers who have to work their way into trail shape. So based on this (admittedly anecdotal and very limited) bit of data perhaps it makes more sense to compare a SOBO speed hike attempt to the generic SOBO thru-hiker when computing ratios than it does to use the "best of NOBO and SOBO" approach that Just Bill is considering. It will be interesting to see by the end of the hike how Matt Kirk's averages compare.

Looking at Matt and Jen's hikes side by side I am struck how three out of the first four sections the ratios seem similar but in the Stratton to Gorham section Matt actually hiked a little quicker with a pack than Jen did without one. I seem to remember though, that JPD was fighting through a bad case of shin splints in this section in her hike, so maybe that slowed her down.

Thanks for providing the data in easy to comprehend tables, Just Bill, and thanks for the suggestions, Odd Man Out.

(edit: Whoops, I read table 6 incorrectly. I now see that the ratios I was looking at that matched up so closely with JPD's hike are indeed for a "best of" NOBO or SOBO hike and not just SOBO. Looks like maybe that is a good model for gauging pace on speed hikes, at least based just on JPD's hike. Sorry for the confusion, Just Bill!)

Odd Man Out
07-15-2013, 00:49
So if I use Just Bill's suggesting of best segment time between NOBO and SOBO, and scale up proportionally to the slowest segment (the Whites), I can determine hiking paces for various overall thru-hike lengths. If I calculated correctly, to finish in 60 days, you need to average 25.3 MPD through the Whites. Using this as the ideal pace to match for a 60 day thru hike I got these numbers as a benchmark for Matt's hike. For fractional days I split the miles for the days between the MPD for the two segments by fraction for each day. By this metric, Matt is way ahead. Do you know where he got to on day 24?

22734

Just Bill
07-15-2013, 12:18
Map Man- Thanks for the review and double check. It is spooky- but all your work on the data sets you produced seem to not only sort out some of the relative difficulty of each section, but by looking at sections, rather than days, we can take smooth out some of the Awesomely bad/good days we all have. I just finished Jen's book new book, you are correct; she fought not just shin splints, but hypothermia in the whites. I think in general, the data supports something that we all agree on regarding the AT; you can only move as fast as the trail allows. No matter what kind of shape you're in, you can only travel so fast (for a sustained period). Pack or no pack the terrain is what it is, the only separation is your personal endurance.

Just Bill
07-15-2013, 12:30
Odd Man Out- I concur with Jersey Joe's post, Matt confirms on his day 25 post he stayed at 845.1- around 921 on day 26, but we'll have to wait for the next post to confirm. See the attached. I created a little smoother version based upon 26 MPD for the baseline and created a schedule with whole day mileages to smooth out some of the "digital" splitting of individual days. It's a hair over for mileage, but I would consider it a pretty good pace to work off of, with a little fluff factor and an open day 60 (zero) just in case. Matt's been ahead since day 1, but this "smoother" version puts him 66 miles ahead of schedule. I think this is the schedule I would use- as it's sectionally realistic and gives you a little "play". As a sample of one (or two if you count Jen) I think it's a pretty good guide. Matt (God and the trail willing) will provide a good second set of data to compare it to.22738

Just Bill
07-15-2013, 12:56
Also- a heartfelt thanks for your time and effort on this. Obviously this is a personal search for this type of data- but for us as a community, at this point there is no metric or relevant goal for an aspiring record breaker. My goal is this- before spouting off your mouth, or deluding yourself too much- is it possible for an aspiring record breaker to complete a Tune-up trip of any section on the trail and have a good idea where they stand? I think this is close. Any further help, tweaks, or double checking of the math, the premise, etc. is greatly appreciated. Nobody likes to see folks going for this who are unqualified, but on the flipside; how do you know you're qualified? For me personally: the best section on my tune-up trip was NOC to Hot Springs. I had a wrong way on day 4. Not counting that- 28.75 MPD, counting that-31.2 MPD. If this formula is correct, and available as a guide- a prospective record breaker can attempt a section as a tune-up trip and see if it's time to open their mouth. For me I can say that I am off target about 8 MPD- Not time to fill the drop boxes, but not far enough off to give up either. With some type of guide, this avoids the "If I need 36.5 MPD, and I did that around Harpers then I'm ready!" "Nope, you needed about 42 for that section- Keep working at it, but don't call in the local paper just yet." It's not enough to have finished before, or to have done some good sections on that hike- but to truly know where you are at. The negative comments just fuel the aspirant's fire- but with some cold hard way to judge your progress...you have to face reality. Maybe at some point, if this (or something better) is available we won't all have to deal with too many "yahoos" and can put our efforts into helping folks like Matt do something exceptional. He was on here too...