Decimalised Green Points
by Max Bavin

Those of you who have played in recent national Green Point competitions may have noticed that Green Point awards have now become decimalised (to two decimal places) in place of the more traditional quarters, halves, three-quarters or whole numbers.

The change was introduced this season, as announced on page 53 of the 2010/11 Member’s Diary & Handbook last year. Please be assured that the net effect is very much the same as before; it’s just that now there is a little more science involved in the calculations than was previously the case. We haven’t yet introduced these changes into the one-day joint venture schedules, though the plan is to do so sometime in the near future.

Previously, awards were devised event-by-event on a largely subjective basis. Often awards went unchanged from one year to the next, even if the nature of the event had changed in the meantime. The net effect was that some anomalies were beginning to creep in such as awards being too high at some events, and too low at others.

The object of the new scheme is to put things on a rather more formal basis, whilst also attempting to remain as loyal as possible to the previous scheme. To this end, we set about devising two separate sets of formulae:-

i) a formula to calculate what the top (winning) award should be. This is based on five separate factors:-

This will normally be expressed as a whole number, though in the case of a very small event it might be expressed to the nearest multiple of 0.5. Should the formula produce a significantly different result to what used to be the case (thankfully there are very few such cases), then we’ll make the change (increase or decrease) gradually over the next year or two.

ii) a formula to calculate the awards for the subsequent places (2nd place and below).

The objective here was to retain the system wherein there was quite a big gap between 1st and 2nd, then a slightly smaller gap between 2nd and 3rd, and so on until eventually the scale became linear down to the last award receiving position. There are three relevant factors:-

Again, staying as loyal as possible to the previous subjective system, the result is a sort of 1/x curve until about half the awards have been calculated, after which subsequent awards reduce in a straight line down to the last award receiving position.

We’re not going to publish the actual formulae here; they are actually rather complex and (trust us) the average reader would not be in the slightest bit interested. However, if you want a bit of fun (?) you can visit this link to see what a typical schedule might look like.

For example, if you played in the 2011 Portland Pairs, the top award on the session only ranking lists was 2.50, the minimum award was 0.50 and the number of awards was 92 (one-quarter of the field). For the overall rankings, the top award was 8.00, the minimum award was 1.00 and the number of awards was 183 (one-half of the field).

Match winning awards

The more obvious part of the decimalisation process which you’re likely to notice is that 'awards for matches won' have also been fully decimalised based on the number of boards played in the match.

The actual formula is ‘Boards divided by 29’, with any fractions being rounded upwards. The effect is that the much loved 7-board match stays at 0.25 Greens for a win. But if you visit (say) Brighton this year and play 8-board matches, then you’ll get 0.28 per win! Of course, drawn matches now only receive one-half of these numbers (but, again, any fraction is rounded up; so 0.13 for a draw in a 7-board match).

Max Bavin