Chips3 & Rinderele B
Scoring Systems

High-point systems are scoring systems in which higher scores are better than lower; they work the opposite of traditional low-point systems, in which a lower score is better.

High-point systems are useful in long series, because they reduce the work of scoring those who did not compete. During a long series, the number of "DNC" boats in a particular event is often greater than those who did compete. A low-point system would require calculating points for boats which did not race. A high-point system merely gives them zero points for events in which they did not compete.

SAIL has experimented with various scoring systems and made Chips3 the scoring system for its season-long Championship Tours. Some clubs have adopted it for their long series scoring as well.

Chips Scoring System

The Chipstead, or Chips, scoring system was developed in England to replace the the Rinderle B system for long series. It is now in its third version, Chips3. A lengthy description of its evolution is at http://styvechale.net/pdf/chips3.pdf. Another description is at "All about CHIPS" on the Chipstead, UK Sailing Club website.

Chips3 is a system implemented in the SailWave computer-scoring program -- an essential requirement for SAIL to use it for its Tour Championships. It recognizes a "percentage of excellence" in performance over an entire season, rewarding the sailor with the ability to finish in the highest percentage position all season long. .

Illustrative Table:

The table below illustrates approximately how Chips 3 works. It may not completely & accurately represent the scoring.

	1	2	3	4	5	6	7	8	9	10
Place	Competitors:
	Points:
0	162.9	101.8	102.4	103.0	103.4	103.8	104.0	104.2	104.3	104.4
1	81.4	83.7	85.6	87.2	88.6	89.7	90.6	91.3	92.0	92.5
2		41.9	57.1	65.4	70.9	74.7	77.6	79.9	81.8	83.2
3			28.5	43.6	53.1	59.8	64.7	68.5	71.5	74.0
4				21.8	35.4	44.8	51.8	57.1	61.3	64.7
5					17.7	29.9	38.8	45.7	51.1	55.5
6						14.9	25.9	34.3	40.9	46.2
7	-						12.9	22.8	30.7	37.0
8	-							11.4	20.4	27.7
9	-								10.2	18.5
10	-									9.2

Formula-based:

Chips3 scoring is based on a mathematical formula, which is entered into SailWave:

S_p,n = 95*[((n+1-p)/n)*(1-0.986682*e^-0.1622*n) + 0.81475*e^-0.1622*n] + 5
Chips3 computation formula

The equation above is a simplified, computational form of:

Chips3 formula genral form

S_p,n = the score for a specific place and a given number of competitors
n = the number of competitors,
p = the place for a specific competitor,
d = 5, a number found by many trials & which avoids "DNF" receiving no points,
e = the root for natural logarithms, approx. ~2.78,
k, b, & c are constants replaced with numbers in the computational form.

The same formula may be entered into a computer spreadsheet if not using Sailwave.

Explanation:

This system starts by assuming:

That first place can never attain a score higher than 100 & that the score should approach 100 only with sufficiently large fleets,
That the differences between places should decrease as the number of competitors increase (2^nd out of 10 is better than 2^nd out of 3), &
That last place scores should be higher for smaller fleets than bigger (2^nd out of 2 is better than 20^th out of 20).

In effect, Chips3 starts by determining a score for a place one better than 1^st ("Place Zero") and a spread between places, both based on the number of competitors. The actual scores are then calculated by multiplying the place times the spread and subtracting the product from the Place = Zero score.

An advantage of Chips3 is that mid-fleet scores (2^nd of 3, 3^rd of 5, 4^th of 7, etc.) are all near 50 points. Mid-fleet racers are not punished as much as by other systems.

"Letter Scores":

The way in which SAIL uses the system reduces concern about letter scores (DNF, etc.). It takes final positions from multi-race regattas as the input to its Tour scoring. Clubs who use Chips3 for long series may use the language from their sailing instructions (e.g., "DNF = finishers + 1") to convert a letter score to a place score. (The SIs should then describe competitors to be scored as those ranked as starters.)

Rinderle B

Chips developed from the Rinderle B scoring system, a high-point system whose origins are hazy, but which has been used by the Gulf of Maine Racing Association. It's thought that the system was was devised in the early 1980s by a ‘Jim Rinderle of Marblehead’ with these goals:

Preserve a bonus for winning;
Have a scoring system that reflects the fact that it is harder to be first among 8 than to be first among 4;
Have a scoring system that reflects the fact that it is more difficult for an average racer to achieve a mid-fleet finish in a small fleet because small fleets usually include a large fraction of the best sailors (e.g. bad weather results in a small fleet because the weaker sailors stay at home);
Create a scoring system that makes an incentive to race.

Perceived problems with the Rinderle system were:

It did not fulfill the "incentive to race" goal; 2^nd out of 2 competitors gets the same points (10.5) as 25^th out of 25.
Mid-fleet finishers were insufficiently rewarded.
It was entirely a table-based lookup system & less susceptible to computerized scoring.

Rinderle B Scoring Tables

For 1 to 10 Competitors
Places	Starters
	1	2	3	4	5	6	7	8	9	10
	Points
1	79.1	81.3	83.6	85.8	87.8	89.6	91.2	92.6	93.9	95.0
2		10.5	43.0	56.8	65.0	70.7	75.0	78.5	81.3	83.6
3			10.5	33.7	46.9	55.7	62.1	67.1	71.2	74.5
4				10.5	28.7	40.6	49.2	55.8	61.1	65.3
5					10.5	25.6	36.3	44.5	50.9	56.2
6						10.5	23.4	33.2	40.8	47.1
7							10.5	21.8	30.7	37.9
8								10.5	20.6	28.8
9									10.5	19.6
10										10.5

For more on Rinderle B, click here.

Cox-Sprague

SAIL previously used another high-point system, Cox-Sprague, to score its Tour Championships. In some respects, it is similar to Chips3 and Rinderle B in some respects. Like Rinderle B, it is a table-based system.

However, Cox-Sprague was found to be cumbersome to use and for competitors to understand.

Acknowledgements

Our thanks to Malcolm Clark, author of "From Rinderle B to the Chipstead High Point Scoring method, version 3", published at http://styvechale.net/pdf/chips3.pdf (the source of the above tables ) and to the Gulf of Maine Racing Association. Also, see Clark's http://styvechale.net/scoring.htm.

Revised: Wed, 23 Dec 2009

Chips3 & Rinderele B Scoring Systems