[NSRCA-discussion] FAI 1/2 points

Mon Aug 1 18:06:13 AKDT 2016

In my view the rounding of a half point deduction (in either direction) is nonsense. Then there’s the issue of how whole points for small errors fit within the 1 / 15 rule.

“5B.8.2. THE 1 POINT PER 15 DEGREE RULE
This basic rule provides a general guide for downgrading deviations from defined manoeuvre geometry. 1 point must be subtracted for each approximate 15 degrees deviation. In general, lines must be judged more critically than deviations in yaw or roll.”

The 1 / 15 rule provides a metric and in some instances provides a conflict, without using half points, when a smaller defect occurs. There is wording in some (unofficial) documents that states a defect of “up to” 15 degrees requires a one point deduction. Logic (to me) suggests that this is not valid basis 5B.8.2. Considering something significantly less than approximately 15 degrees as a “slight defect” and nearly 15 degrees as a “defect” seems to fit better. (Ambiguous wording like “slight defect” doesn’t define much.) In both cases a score deduction should be applied and 1/2 points really help a judge correctly differentiate maneuver quality. But again – rounding the 1/2 point deduction negates any scoring precision achieved. 

And it’s not like half points haven’t worked well in the AMA classes. I’ve never understood the reluctance of the F3A Subcommittee to incorporate them, then when they finally do they add some rounding junk – go figure.

Earl

From: Stuart Chale via NSRCA-discussion 
Sent: Monday, August 01, 2016 7:08 PM
To: Peter Vogel ; General pattern discussion 
Subject: Re: [NSRCA-discussion] FAI 1/2 points

Even if the interpretation is wrong and an 8.5 should be rounded down to an 8 instead of rounded up to a 9 is that any better? 

The better flyer getting all 8.5's gets the same score as the flyer with all 8's, and loses if one maneuver is a 9 instead of an 8.

Stuart

On 8/1/2016 4:56 PM, Peter Vogel via NSRCA-discussion wrote:

  I still question the interpretation of the rules here.  This is from the FAI sporting code: 

  Each judge gives a mark for each manoeuvre during a flight. Assuming the highest mark 10 at the start of each manoeuvre, every defect is subject to downgrade of the mark in whole numbers (or in half numbers for slight defects, but in sum resulting in up-rounded whole numbers). A high score should remain only if no substantial, severe or multiple defects are found.

  The original methodology I had implemented in the electronic scribe resulted in a cumulative downgrade of 1.5 points being up-rounded to 2 points of DEFECT, resulting in a final score of 8, effectively rounding the final score DOWN.  We asked for a clarification from Michael Ramel but I'm not sure he understood the clarification we were asking for!  The current implementation in both MasterScoring and the electronic scribe is that 1.5 is deducted from the final score (8.5) which is then up-rounded to 9.  What I do not like about that is it means that a maneuver with a total of one minor defect (for a 0.5 deduction) gets a perfect 10 instead of an imperfect 9.

  Peter+

  On Mon, Aug 1, 2016 at 1:31 PM, John Pavlick via NSRCA-discussion <nsrca-discussion at lists.nsrca.org> wrote:

    "No particular reason was given for the rounding up... They preferred it versus rounding down."

    Well that sounds like a scientific explanation. Since it makes no reference to how floating point numbers and quantization errors actually work, we’ll have to accept it as fact. J

    John Pavlick

    Cell: 203-417-4971

    Integrated Development Services

    From: NSRCA-discussion [mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of Scott Smith via NSRCA-discussion
    Sent: Monday, August 01, 2016 3:43 PM
    To: Stuart Chale; General pattern discussion
    Subject: Re: [NSRCA-discussion] FAI 1/2 points

    I asked that same question and was told:

    "No particular reason was given for the rounding up... They preferred it versus rounding down."

    On Mon, Aug 1, 2016 at 3:18 PM, Stuart Chale via NSRCA-discussion <nsrca-discussion at lists.nsrca.org> wrote:

    Some ideas and changes are just plain stupid!  There I said it :)

    I have always hated the fact that some judging criteria and downgrades
    were different in FAI and AMA.  Makes judging which is a tough job to do
    right even tougher.  You have to know 2 different sets of rules and in
    the long run only lowers the accuracy of judging, most likely more so
    for the FAI fliers.  But that is another can of worms.

    I thought that allowing 1/2 points in FAI sounded like a good idea, we
    are used to it in the rest of the classes.  And since the FAI pilots are
    in most part the better fliers they are more likely to make the 1/2
    point errors as compared to the greater inaccuracies usually seen in the
    lower classes.

    But wait an 8.5 becomes a 9, and a 9 is still a 9  ??????

    So just to prove how silly this idea can be I used Scott's scoring
    program and ran a fictitious contest with 2 flyers and 2 rounds.  I used
    a couple of friends as contestants so to not offend anyone.  I also had
    to use the masters sequence as an example, as the program automatically
    rounds up FAI scores.

    Hopefully the PDF files are attached.

    Each flyer received identical scores in each of their 2 flights. AR
    received all 7.5's except one maneuver which was an 8.5,  and DL all 8's
    .  In round 1 scores were not rounded up and in round 2 the scores were
    rounded up as they would automatically be done in FAI.

    Look at the files for AR round 1 and DL  round 1.  It would seem pretty
    obvious who should win that round and without rounding up AR gets a
    947.75 to DL's 1000.

    Note that every maneuver but one was judged higher for DL.

    Now look at AR round 2 and DL round 2 rounded up.  The same exact judges
    scores with only 1 maneuver scored higher for AR, but due to the
    rounding up AR wins the round 1000 to 989.86.

    Now this is the extreme and unlikely to actually happen in a contest to
    this extent but just the fact that it works this way makes the whole
    idea of rounding up ridiculous.

    Is there really an argument that this is a good thing?

    Stuart C.

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