the migration from aspnto phrf ns prepared by: rod stright prepared for: nsya handicap committee...
TRANSCRIPT
The The
Migration FromMigration From
ASPNASPN
ToTo
PHRF NSPHRF NSPrepared By: Rod StrightPrepared By: Rod Stright
Prepared for: NSYA Handicap CommitteePrepared for: NSYA Handicap Committee
April 28, 2009April 28, 2009
1. Objective of Presentation
The purpose of this presentation is to The purpose of this presentation is to provide sailors across Nova Scotia with an provide sailors across Nova Scotia with an understanding of the new PHRF NS rating understanding of the new PHRF NS rating system and the process used to get there system and the process used to get there from our old handicap system ASPN.from our old handicap system ASPN.
2. The History of ASPN
• Started as a Local Handicap system after WW IIStarted as a Local Handicap system after WW II• ASPN - Atlantic Speed Potential NumberASPN - Atlantic Speed Potential Number• Was refined and developed into ASPN under Mike Eames Was refined and developed into ASPN under Mike Eames • ASPN is a derivative of US Sailing PHRF ASPN is a derivative of US Sailing PHRF • Is a time on time handicap system as opposed to a time on Is a time on time handicap system as opposed to a time on
distance systemdistance system• Has been in use for more than 40 years in its present Has been in use for more than 40 years in its present
formatformat• Has been used in reviewing the performance of yachts Has been used in reviewing the performance of yachts
racing in Nova Scotia during those 40+ yearsracing in Nova Scotia during those 40+ years• Unique to Nova ScotiaUnique to Nova Scotia
3. The History of PHRF
• PHRFPHRF - Performance Handicap Racing Fleet - Performance Handicap Racing Fleet• The standard keelboat handicapping system used The standard keelboat handicapping system used
throughout North Americathroughout North America• Handicaps are adjusted based upon observed performance Handicaps are adjusted based upon observed performance
on the race courseon the race course• PHRF ratings are derived based upon the difference in PHRF ratings are derived based upon the difference in
seconds per mile between a scratch boat and the rated boat seconds per mile between a scratch boat and the rated boat sailing over a one nautical mile circular coursesailing over a one nautical mile circular course
• PHRF Ratings are Time on DistancePHRF Ratings are Time on Distance
4. Moving to PHRF Time on Time • Time on distance racing still has its place• Most areas prefer Time on Time racing as it is a fairer
system of handicap racing over shorter courses and it better addresses a larger handicap spread
• To get to Time on Time PHRF from Time on Distance there is a “Time Correction Formula”
• TCF = A / (B + PHRF)• A = doesn’t change results selected to give the mid boat a
TCF of 1• B = number of seconds to sail one mile in expected
conditions• NSYA Recommended values A 695 and B 525• Clubs may use what they want• TCFs are posted on NSYA website under view button
5. Advantages of PHRF Well documented systemWell documented system Recognized all over North AmericaRecognized all over North America A lot of work has already been doneA lot of work has already been done ASPN some serious flaws (skew and limitations ASPN some serious flaws (skew and limitations
due to handicap spread)due to handicap spread) Ease of reference on boatsEase of reference on boats Flexibility to go to Time on Distance if desiredFlexibility to go to Time on Distance if desired Flexibility to adjust B Factor for certain type of Flexibility to adjust B Factor for certain type of
races (port to port, windward/leeward etc.)races (port to port, windward/leeward etc.) Finer adjustments and more of them if desiredFiner adjustments and more of them if desired
6. The Decision to Go PHRF NS• On October 7, 2008, the NSYA Board of Directors On October 7, 2008, the NSYA Board of Directors
approved the recommendation of the Handicap Committee approved the recommendation of the Handicap Committee to convert from our current ASPN system to a PHRF to convert from our current ASPN system to a PHRF Time-on-Time system. Time-on-Time system.
• 2/3 support from member clubs was a requirement2/3 support from member clubs was a requirementConditions associated with the decision:Conditions associated with the decision:
PHRF format, PHRF format, Time-on-Time racing. Time-on-Time racing. Existing relationship between boats in our fleet to Existing relationship between boats in our fleet to
be maintained be maintained will not adopt ratings from other areas but will will not adopt ratings from other areas but will
continue to provide our own ratings, continue to provide our own ratings, forty years of local experienceforty years of local experience active participation of our Handicap Committee. active participation of our Handicap Committee.
7. The Processes to Obtain PHRF NS Ratings
• List of Boats with well-established ASPN ratings and well established List of Boats with well-established ASPN ratings and well established
ratings in other areas of North America was generated.ratings in other areas of North America was generated.
• List was further reduced to a dozen between 100 and 144 ASPNList was further reduced to a dozen between 100 and 144 ASPN
• Current PHRF numbers for this list of boats were obtained from five Current PHRF numbers for this list of boats were obtained from five
representative areas across North Americarepresentative areas across North America
• An average PHRF number was then calculated for each listed boat An average PHRF number was then calculated for each listed boat
based on the PHRF numbers from these other areasbased on the PHRF numbers from these other areas
• Another list was generated comparing the ASPN numbers for the list Another list was generated comparing the ASPN numbers for the list
of boats to the PHRF numbers for the same list of boats.of boats to the PHRF numbers for the same list of boats.
• Mathematically curve was then generated that compared PHRF Mathematically curve was then generated that compared PHRF
numbers to ASPN numbers (90-151)numbers to ASPN numbers (90-151)
• Final list was generated that translated ASPN base numbers to PHRF Final list was generated that translated ASPN base numbers to PHRF
base numbersbase numbers
8. PHRF Adjustments
• Only the adjustments applied under the ASPN System Only the adjustments applied under the ASPN System were usedwere used
• Similar adjustments were reviewed for the 5 selected Similar adjustments were reviewed for the 5 selected PHRF areasPHRF areas
• Comparative adjustment analysis for the five PHRF areas Comparative adjustment analysis for the five PHRF areas with ASPNwith ASPN
• New PHRF NS adjustments determined by unanimous New PHRF NS adjustments determined by unanimous agreement of the NSYA handicap committee.agreement of the NSYA handicap committee.
9. Points to Keep in Mind• When ASPN was originated the ratings were between 90 When ASPN was originated the ratings were between 90
and 120, now they are between 90 and 153.and 120, now they are between 90 and 153.• Under ASPN I ASPN point was 6 sec/mile at the low end Under ASPN I ASPN point was 6 sec/mile at the low end
(100) and 3 sec/mile at the high end (Unfair)(100) and 3 sec/mile at the high end (Unfair)• ASPN was based on PHRF in the first place but using a B ASPN was based on PHRF in the first place but using a B
factor of 400 which is for a port to port downwind race. factor of 400 which is for a port to port downwind race. This favored the slower boats a lotThis favored the slower boats a lot
• PHRF have finer adjustments and are usually 3 sec/milePHRF have finer adjustments and are usually 3 sec/mile• PHRF NS has now 1 sec/mile differences in ratingsPHRF NS has now 1 sec/mile differences in ratings• In one design racing the first boat usually beats the middle In one design racing the first boat usually beats the middle
boat by 18 sec. Given that 1 sec/mile cannot be measuredboat by 18 sec. Given that 1 sec/mile cannot be measured• Base Rating Relationship between boats racing here has Base Rating Relationship between boats racing here has
been maintainedbeen maintained
9. Points to Keep in Mind (Cont’d)• PHRF NS ratings cannot be compared directly PHRF NS ratings cannot be compared directly • Each PHRF area has different PHRF Ratings as well as Each PHRF area has different PHRF Ratings as well as
different fleet mixes, different sailors, different wind different fleet mixes, different sailors, different wind conditions, different currents and different sea states.conditions, different currents and different sea states.
• 1 sec/mile is 0.17 ASPN points which is negligible1 sec/mile is 0.17 ASPN points which is negligible• Under ASPN a higher number was fasterUnder ASPN a higher number was faster• Under PHRF a lower number is fasterUnder PHRF a lower number is faster• Under ASPN the adjustments were made to the Time Under ASPN the adjustments were made to the Time
Correction FactorCorrection Factor• Under PHRF the adjustments are made to the base ratingUnder PHRF the adjustments are made to the base rating• ASPN had built in B factor that selected Tanzer 22 as ASPN had built in B factor that selected Tanzer 22 as
median boat NSYA median boat under PHRF is is C&C30 median boat NSYA median boat under PHRF is is C&C30
10. Scoring Results PHRF NS
Options are:Options are:
A.A. SailwaveSailwave
B.B. ExcelExcel
C.C. WinregattaWinregatta
10. A Sailwave
• Comprehensive Race Scoring softwareComprehensive Race Scoring software• Available free from (www.sailwave.comAvailable free from (www.sailwave.com)) • Worldwide softwareWorldwide software• Continually updatedContinually updated• Most widely used race scoring software available Most widely used race scoring software available
today for sailboat racingtoday for sailboat racing• Well suited to PHRF and can import all data Well suited to PHRF and can import all data
required required • User’s Guide developed and supplied by NSYAUser’s Guide developed and supplied by NSYA
10. A Sailwave
10. B Excel
• Custom sheet developed by NSYACustom sheet developed by NSYA• Local systemLocal system• Widely available programWidely available program• Not racing systemNot racing system• SimpleSimple• Can be used when other systems not Can be used when other systems not
available (backup)available (backup)
10. B Excel
10. C Winregatta
• Been in use for a long timeBeen in use for a long time• Users familiar with systemUsers familiar with system• UnsupportedUnsupported• Requires conversion of TCF to %Requires conversion of TCF to %• Will fail as time progressesWill fail as time progresses• NO LONGER AVAILABLE NO LONGER AVAILABLE
10. C Winregatta
11. Conclusions
1.1. ASPN has served us well but needs to goASPN has served us well but needs to go
2.2. Winregatta has done likewise but will not be supportedWinregatta has done likewise but will not be supported
3.3. Time on Time racing is the best match to handicap racing Time on Time racing is the best match to handicap racing available in North Americaavailable in North America
4.4. No handicap system is perfectNo handicap system is perfect
5.5. 40 year performance history of ASPN has been preserved40 year performance history of ASPN has been preserved
6.6. The migration has been complicated and there will be The migration has been complicated and there will be growing pains and teething problemsgrowing pains and teething problems
12. NSYA Recommendations
• Clubs should move to PHRF NS as soon as possible, 2010 Clubs should move to PHRF NS as soon as possible, 2010 is mandatory – ASPN will be gone in 2010 - is mandatory – ASPN will be gone in 2010 -
• Use the system as recommended for 2009 Use the system as recommended for 2009 • Move from Winregatta to Sailwave in conjunction with Move from Winregatta to Sailwave in conjunction with
move to PHRF NSmove to PHRF NS• Accept the fact that no handicap system is perfectAccept the fact that no handicap system is perfect• Issues should be reported to the Club handicappers as Issues should be reported to the Club handicappers as
promptly as possible.promptly as possible.• Remember we are moving from a system that is very Remember we are moving from a system that is very
coarse to one that is very fine 1 sec = .17 ASPN pointcoarse to one that is very fine 1 sec = .17 ASPN point• Sail fast have funSail fast have fun
Info on NSYA website
• www.nsya.ns.ca/www.nsya.ns.ca/• Under PHRF RacingUnder PHRF Racing• Yacht RatingsYacht Ratings• Base ratingsBase ratings• AdjustmentsAdjustments• PHRF NS (explanation)PHRF NS (explanation)• Etc.Etc.
Presented by: NSYA Handicap Committee
Volunteers not professionals
Not paid
Supporting our sport
If you like it tell your friends
If you have a problem tell your handicapper who is also your NSYA Handicap Committee Rep