[NSRCA-discussion] Scoring Process Question

[vicenterc at comcast.net]

George,

I don't think that we have a problem since all calculations we are using the same number of digits for each pilot.  It will be a mess if for each pilot we use different number of decimals for scores, K-Factors and totalization.  In our calculations the only variables is the score and K-Factors.  The normalization is just to assign 1000 point to the winner of each round (maximum of sum of  scores x K-factor).  In this estimates, we don't apply any statistics.

We use two decimal points to estimate the normalized score over the 1000 points.  That gives more than enough precision for this type of estimate.

Regards,

--
Vicente "Vince" Bortone

-------------- Original message -------------- 
From: <glmiller3 at suddenlink.net> 

> I'm going to open a can of worms here in hopes of coming up with a better system 
> out of the discussion. Perhaps this has been discussed before and I'm not aware 
> of it. Let me preface this by saying I am not a mathematician or statistician, 
> but I have some familiarity with both subjects and the following question has 
> been growing in my mind for some time. 
> 
> It seems to me that we are judging our maneuvers with limited accuracy (within 1 
> point in FAI and X.5 points in AMA classes) we are then creating the ILLUSION of 
> accuracy by multiplying that score by a K factor and then normalizing to a 1000 
> point scale. Here is a fairly brief explanation of "Significant Digits" that 
> I've copied from the web which will introduce you to this thought if you haven't 
> seen it before: 
> 
> ****"SIGNIFICANT DIGITS 
> 
> The number of significant digits in an answer to a calculation will depend on 
> the number of significant digits in the given data, as discussed in the rules 
> below. Approximate calculations (order-of-magnitude estimates) always result in 
> answers with only one or two significant digits. 
> 
> When are Digits Significant? 
> 
> Non-zero digits are always significant. Thus, 22 has two significant digits, and 
> 22.3 has three significant digits. 
> 
> With zeroes, the situation is more complicated: 
> 
> Zeroes placed before other digits are not significant; 0.046 has two significant 
> digits. 
> Zeroes placed between other digits are always significant; 4009 kg has four 
> significant digits. 
> Zeroes placed after other digits but behind a decimal point are significant; 
> 7.90 has three significant digits. 
> Zeroes at the end of a number are significant only if they are behind a decimal 
> point as in (c). Otherwise, it is impossible to tell if they are significant. 
> For example, in the number 8200, it is not clear if the zeroes are significant 
> or not. The number of significant digits in 8200 is at least two, but could be 
> three or four. To avoid uncertainty, use scientific notation to place 
> significant zeroes behind a decimal point: 
> 8.200 ´ has four significant digits 
> 8.20 ´ has three significant digits 
> 
> 8.2 ´ has two significant digits 
> 
> Significant Digits in Multiplication, Division, Trig. functions, etc. 
> 
> In a calculation involving multiplication, division, trigonometric functions, 
> etc., the number of significant digits in an answer should equal the least 
> number of significant digits in any one of the numbers being multiplied, divided 
> etc. 
> 
> Thus in evaluating sin(kx), where k = 0.097 m-1 (two significant digits) and x = 
> 4.73 m (three significant digits), the answer should have two significant 
> digits. 
> 
> Note that whole numbers have essentially an unlimited number of significant 
> digits. As an example, if a hair dryer uses 1.2 kW of power, then 2 identical 
> hairdryers use 2.4 kW: 
> 
> 1.2 kW {2 sig. dig.} X 2 {unlimited sig. dig.} = 2.4 kW {2 sig. dig.} "****** 
> 
> My Point is this: 
> 
> I've seen many contests decided by less than 10 points on a scale of 4000 which 
> has been expanded from (at most) 2 significant digits. As a matter of 
> "statistics" I think that any separation of less than 100 points (two 
> significant digits, ie, 3X00 points) is "artificial accuracy". Unfortunately, 
> I don't have any great ideas about how to improve upon the current system, I'm 
> just pointing out what I think is a scientifically valid problem with it. 
> 
> I smile when I see round scores posted to ten thousanths of a point on a scale 
> that has been expanded from two significant digit accuracy to a 1000 point 
> scale. This turns a two significant digit answer into eight significant digits! 
> (ie, 1234.5678) I think that scientifically, the scores would be more 
> accurately posted as in scientific notation at x.x * 10 to the second power. 
> Most of the contests that I've been to this year have been decided essentially 
> by random statistical "noise" rather than actual scoring decisions. 
> 
> 
> Has anyone ever thought/talked about this before ? 
> 
> Let me add, that despite what I think are statistically invalid methods, in most 
> cases the system seems to work pretty well. In general the superior pilots get 
> enough better scores to overcome the "noise" but it sure would be nice to come 
> up with a more mathematically valid solution, IMO. 
> 
> George 
> 
> 
> 
> 
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