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Re: [RC] LD/50 times - Diane TrefethenI have received some gentle and some not so gentle :) chiding as a result of my comments on ride times for LDs. My basic response is, "Don't shoot the messenger".Truman did a study on speeds and deduced from the records that the top LDs rode more slowly than the top 50s. What did he use for this study? The AERC ride result records. Are these records accurate? That last is the question I was addressing. My point was that if there are SOME records so badly out of whack that one can spot them knowing nothing about the ride in question, how many more are equally wrong but just harder to spot? For instance, according to the record, the Tidioute Challenge 25 on 08-Jul-06 was won in 4:16. WON! It is not impossible that the winning time was so slow but when the winner of a 25 mile ride goes only 5.86 mph, a reasonable person will think, "Can that be right?" So you look at the 50 that was run concurrently. That ride was won in 5:34, an average of 8.98 mph. That is slow too but not outlandishly so. I think Truman said the 50s run about 15% faster than the LDs. In this ride the record says they ran 53% faster. David said, "I believe it was you earlier admonishing Truman about statistics. Don't make the even more fundamental mistake of comparing a statistically significant sample of hundreds of rides to anecdotal evidence." I didn't. I did not say that because some LD rides appear to include hold time, probably all do or that because I was passed by 25ers, all LDs go fast. I said some LDs were reported incorrectly and I couldn't tell if maybe all were and that the 25ers that beat me to the lunch stop clearly rode faster than I did. Several RMs have written that no way do they include hold time and I believe them. But how about a new RM and/or a Ride Sec'y that hasn't done it before? No matter how carefully you do a study, if the data is flawed, the study results are unreliable. In the case of the AERC LD times, the question is not IF the data is flawed, it is HOW MUCH is the data is flawed. David also pointed out, "You'll find finish times on 50's up in the 11 hour range, too". Absolutely true. And even more significantly, you'll find some in the 1-2 hour range. It seems that besides transposing digits and including hold times, some rides (at least one that I know of - Gold Coast 50, 1988) make the mistake of reporting what time it was when the riders crossed the finish line. If that were to happen today, or if it happened in 2002, at a ride that was holding both an LD and a 50, the difference wouldn't be 15% or 53%. It would be around 1900%. But this probably couldn't happen. I bet Mike's software has traps for 25s that take more than 6 hrs. =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Ridecamp is a service of Endurance Net, http://www.endurance.net. Information, Policy, Disclaimer: http://www.endurance.net/Ridecamp Subscribe/Unsubscribe http://www.endurance.net/ridecamp/logon.asp Ride Long and Ride Safe!! =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
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