Data (was PowerCranks Study)

"RACER X" wrote in message
...
Andy,

I really don't understand what you are saying by absolute vs. relative, as
I am
not as familiar with the study as you probably are. But if it's what I
think
it is, the small n number of 12 would still adversely impact the validity
of
that 2% measurement even if it's an absolute measurement (vs. a relative
measurement).


He is saying that the 2% is an increase in total efficiency rather than a 2%
increase relative to the control group.

IOW, say you have a study where the control group is 40% (any metric) and
the study group is 42%. That is 2% increase relative to the whole, but it is
a 5% increase relative to the control group. The reason is that 2 is 1/20th
of 40, or 5/100 = 5%.

People make those mistakes all the time. I notice them the most when people
talk about finance interest rates. Someone will see a loan that is 4.5% vs
5% and say, "That is only .5%". And the real answer is that it is a 10%
reduction.

RACER X wrote in message ...
Like I said Frank, using an "n" number of 12 is already such a significant fault of the study design, that all
you people touting its conclusions are just reinforcing your total lack of understanding of items like
standard deviation, statistics in general, and imprecision of measuring equipment.

All your other discussions are moot because you'll NEVER convince any real scientist that using 12 subjects
can generate meaningful statistics of any kind.

Like I said, it's a fatal flaw and any further discussions of this study that attempt to gloss over the "n"
number problem cannot pass the laugh test.

Racer "Johnny Cochran" X



RACER X:

You've been spending too much time watching Speed Racer (Trixie's hot,
ain't?). If you spent less time watching cartoons and more time
reading about science and statistics, you'd know that 'n' *means*
'number,' and you'd stop looking like a fool by saying 'n number.'
You'd also know that having n = 12 is not a 'fatal flaw.' Sure, a
higher n would be better - it always is. But if they achieved
statistical significance with n = 12, that may actually indicate a
strong effect. But you don't know what I'm talking about, so I'll
just leave it at that.

When your understanding is incomplete, it makes the correct conclusion
impossible.

It's like that episode of Speed Racer with the Mammoth Car. All
along, Speed and his friends thought the car was being used to
*smuggle* the gold. In the end, it turned out that the Mammoth Car
WAS the gold. WOW. That cartoon kicked ass.

You're really doing a disservice to the name of Zen-Master RACER X.
Cease and desist.

-RJ, n = 1.

You seem quite adept at giving criticism, but don't address it well
when directed at yourself. Coming from a guy who squeezed by his 840
level biostat's course, even I can say that your assessment of n is so
unbelievably simple minded that I wonder where you even arrive at your
conclusions. The power of one's statistics is driven by numerous
factors, with sample size being just one. Furthermore, it is quite
possible to have an n of 12 and adequately detect differences.

Anyone familiar with perfomance based research understands that it is
nearly impossible to perform studies like this one with large samples.
The true worth of this study will be measured by its repeatability
not in your continual blather about its small sample size.

Perhaps you should go back to school and learn something before you
continue with your worthless comments.

CH

Frank,

Museeuw won ALL of his big races while NOT using Power Cranks. Ever think about looking at it that way?

Take that to the bank and cash it.

Racer X


Frank Day wrote:

I have no idea if Museeuw emails other pros about the cranks. Further,
I have never spoken with Museeuw (I don't think he speaks much
english) so I have no clue as to how he trains on the pair of cranks
he has. What I do get is emails from pros telling me Musseuw told
them they needed to get on the cranks.

Frank

Frank


(RK) wrote in message
Biopace still has its advocates. The question is: are they as good as
rotor Cranks? They are being used by some 2nd division pros, Spanish
triathletes, et al. They look to be an eccentric cam device intended
to eliminate the dead spot that Power Cranks emphasize for training.

http://www.rotorbike.com/eng/home.htm

Chrissy,

I'm the only guy here who does what one is suppose to do to a scientific study: challenge it.
That's the very premise of the Scientific Method and it's not only appropriate to do that, but
expected.

Erudite people do not take offense to genuine criticisms.

No relation to Awesomebikedude,

Racer X

chris wrote:

RACER X wrote in message ...
Dude,

I already wrote the only review that matters. Why try to reinvent the wheel?

Racer X

Because, Dude, chowderhead's like you try to make us all think you now
**** from Shinola, but really you just don't want the more learned to
make their own judgements for fear they'll call you on your idiocy.

Now, if memory serves me, I believe a friend of mine reviewed this
paper, or a related one, about a year and a 1/2 ago. Perhaps I can
dig it up.

BTW: You wouldn't be related to Awesomebikedude?

Chrissy,

Using a study with an n number of 12 is almost always, bad news unless
you work in a Dunkin Donuts drive-thru. I respectfully disagree with
you.

Your argument that studies are of this nature are difficult to do
therefore somehow negating the importance of a large n number is a
bizarre argument. Science and statistics don't cut scientists slack in
their study design just because "it's difficult" for them get a large
pool of volunteers. Your results are what they are. And a study that
uses 12 people is not good science. Ask any scientist.

Doing a study with 12 people (6 in each group) is professional suicide.
My coin flip analogy was diluted so that laypeople in this group can
understand why flipping a coin 12 times is not going to give the same
precision of results that flipping it 200 times will.

I agree with you that "the true worth of this study will be measured by
its repeatability." Hopefully, the other researchers will have the
foresight to use a large n sample that won't be laughed at.

Trust me, I know statistics. I've done graduatel level work with DNA
allele frequency statistics - that calculus stats. Your 840 course final
exam is something I could ace in my sleep.

Keep it real brother,


Racer X



chris wrote:

You seem quite adept at giving criticism, but don't address it well
when directed at yourself. Coming from a guy who squeezed by his 840
level biostat's course, even I can say that your assessment of n is so
unbelievably simple minded that I wonder where you even arrive at your
conclusions. The power of one's statistics is driven by numerous
factors, with sample size being just one. Furthermore, it is quite
possible to have an n of 12 and adequately detect differences.

Anyone familiar with perfomance based research understands that it is
nearly impossible to perform studies like this one with large samples.
The true worth of this study will be measured by its repeatability
not in your continual blather about its small sample size.

Perhaps you should go back to school and learn something before you
continue with your worthless comments.

CH

"RACER X" wrote in message
...
Frank,

Museeuw won ALL of his big races while NOT using Power Cranks. Ever think
about looking at it that way?

Take that to the bank and cash it.

Racer X

Dude, they are only used in training and not competition. Not that I give a
crap about these cranks but your arguments are not very convincing. Dan
Connelly had the best response when he said:



Exactly. A better experiment would include other methods of pedal stroke
improvement.
For example, a full-factorial between PC, one-legged pedaling, big gear
climbing,
downhill spin drills, and placebo approaches. Get, say, 10000 cyclists,
and split
'em up.

Of course, in human experiments, degrees of freedom are very expensive.

Dan

Hurdler,

I say "n number" because I want the laypeople in this group to understand why it's wrong. I am aware what the
variable "n" signifies in statistical computations. Let's not hit below the belt.

You and Chris both say you can get "good" results with a 12 subject study. The problem with your response is
you're using the word "good." No scientists uses that word to describe a data set because it's a relative
adjective.

That bike is "good." What does that really mean?

What you are also NOT saying is that you can get MUCH BETTER results using 200 subjects. And the difference
between good results and MUCH BETTER results I submit to you will exceed the 2% efficiency claimed in this study by
the Power Cranks study director.

Why don't you tell me that you can also get "good results" with 8 subjects, or 4 sinjects? How about 2 subjects?

Come back on this newsgroup and tell me exactly how you would rate this same study if it were done using 2
subjects, 4 subjects, 6 subjects, 8 subjects, 10 subjects, and 200 subjects, etc.

You see where I'm going with this argument, don't you? I will prove to you using your own keyboard that you will
agree with me that as the "n" increases, the results get "better." At some point, the n issue becomes neglgible
(i.e. when 200 subjects are used). But using 12 subjects is not good technique.

Studies should be conservative, not risk-taking ventures. If you want me to believe in the results, use 200
subjects in your ****ing study, not a box of Dunkin Donuts as an "n" and a bunch of "it's good enough" arguments.

I threw the number 200 out there because that's a number that isn't going to be attacked easily for an "n"
problem. When you intentionally design a study that uses 12 subjects, you are telling me you are the kind of
person who folds his homework up in his back pocket and does the minimal amount of work possible to get by. You're
a "C" student and when you don't get an A (I would get an A because I used 200 subjects in my experiement model),
you call the teacher a bunch of names and say it's "good enough."

Sorry, but the results of a 12 person study don't impress me like the results of a 200 person study would. No
scientist will refute that argument.

Not even you.

Racer X



Ronaldo Jeremiah wrote:

RACER X wrote in message ...
Like I said Frank, using an "n" number of 12 is already such a significant fault of the study design, that all
you people touting its conclusions are just reinforcing your total lack of understanding of items like
standard deviation, statistics in general, and imprecision of measuring equipment.

All your other discussions are moot because you'll NEVER convince any real scientist that using 12 subjects
can generate meaningful statistics of any kind.

Like I said, it's a fatal flaw and any further discussions of this study that attempt to gloss over the "n"
number problem cannot pass the laugh test.

Racer "Johnny Cochran" X



RACER X:

You've been spending too much time watching Speed Racer (Trixie's hot,
ain't?). If you spent less time watching cartoons and more time
reading about science and statistics, you'd know that 'n' *means*
'number,' and you'd stop looking like a fool by saying 'n number.'
You'd also know that having n = 12 is not a 'fatal flaw.' Sure, a
higher n would be better - it always is. But if they achieved
statistical significance with n = 12, that may actually indicate a
strong effect. But you don't know what I'm talking about, so I'll
just leave it at that.

When your understanding is incomplete, it makes the correct conclusion
impossible.

It's like that episode of Speed Racer with the Mammoth Car. All
along, Speed and his friends thought the car was being used to
*smuggle* the gold. In the end, it turned out that the Mammoth Car
WAS the gold. WOW. That cartoon kicked ass.

You're really doing a disservice to the name of Zen-Master RACER X.
Cease and desist.

-RJ, n = 1.

"RACER X" wrote in message
...
Frank,

Museeuw won ALL of his big races while NOT using Power Cranks. Ever think about looking
at it that way?

Take that to the bank and cash it.

Racer X


Merxkx won all his races without aero bars, disc wheels, clipless pedals, or index
shifting and while wearing wool.

So what?

RACER X wrote:
Trust me, I know statistics. I've done graduatel level work with DNA
allele frequency statistics - that calculus stats.

Oh dear.