Overview of how DBPN ratings are set &ndash Updated 23 September 2008
Many participants in the regattas organized by DBYC first enter without an official
HKPN handicap. In addition, a review of the race results at DBYC has indicated
that even when a boat has received an initial HKPN this has been found to be
out of step with the other boats racing in DBYC regattas, being either
unrealistically harsh for a boat and crew which is new to racing or,
occasionally, overly favorable. Unfortunately HKPN ratings can take many
months to change particularly for boats which race mainly in DBYC organized
races. It was therefore determined that the DBYC would adopt its own rating
system which would provide a more level playing field for the boats which
regularly raced in DBYC events.
The guidelines currently adopted by the DBYC Rating Committee to determine and adjust DBPN ratings are as follows:
- When a new boat joins the fleet the initial DBPN will be set by the DB ratings
committee. When the boat already has an HKPN rating this will usually be
adopted as the starting DBPN. When the boat does not have an HKPN then
the committee will review the ratings given for similar boats racing in
HKPN or with IRC ratings and attempt to set a realistic initial DBPN.
- Following each DBYC race the DBYC race committee will decide if the race results should
be considered to be a qualifying race which would warrant an adjustment to
the DBPNs for boats which have raced in the event. No adjustments will be
made where less than 5 boats have participated in an event (or a division
if more than one division is racing) or where there is good reason to
believe that the race result has been adversely affected by unusual or
anomalous conditions which prevailed during the race.
- Assuming that the race committee has determined that the race was a qualifying
event and adjustments should be made then the standard approach to be
adopted by the ratings committee will be to decrease the rating of the winning
boat by approximately 1% and the second boat by approximately 0.5% and
increase the rating of the boat which came last by approximately 1% and
the boat which came second to last by approximately 0.5%. However
adjustment will never be of a magnitude which would have altered the final
positions in the race and will not usually be greater than a maximum of
1%.
- The 'maximum 1%' rule may be changed for boats which have only recently
received a DBPN. Where a boat is racing in its first two races at DBYC
events the racing committee may make adjustments which exceed 1% in order
to more rapidly bring the adjusted performance of a boat more closely in
line with the DB fleet.
- The rating committee may also make adjustments to a boat's DBPN where
significant adjustments have been made to the boat (for example new high
tech sails replacing worn out canvas rags). These adjustments will be
based where possible on published data, for example the ratings
adjustments which are published on the USPHRF website.
- The ratings committee may also make an adjustment to a boat's DBPN where a
boat changes owner, for example from an experienced racing crew to a first
time racer.
Following a meeting of the HKPN handicapping committee on September 2nd 2008 it was agreed that DBYC races
would in future also be used by the HKPN handicapping committee in their
database for adjusting HKPN ratings. Consequently, where the DBYC racing
committee decides that the race is a qualifying race then the race results will
be provided to the HKPN ratings committee.
In order to attempt to closely align the DBPN system with the HKPN system the DBYC
handicapping committee is making the current DBPN ratings available to the HKPN
ratings committee. Where there is currently a significant disparity between
the HKPN and DBPN ratings the DBPN ratings committee will inform the HKPN
ratings committee whether the DBPN rating is considered to be reasonably
representative of a boat's relative performance in comparison to other boats
with HKPN ratings. This judgement will be based on whether the DBPN has been
determined from a significant number of DBYC races in which other boats with DBON
and HKPN ratings have taken part.
In addition, the DBYC handicapping committee also intends to review the average
ratings of boats which have regularly raced in both DBYC and HKPN qualifying
events and make an adjustment to all the DBYC ratings so that the average DBYC
values are similar to the HKPN values. The aim of this is to ensure that the
two systems do not drift apart.
For any additional information on the DBPN ratings please
call Andy Pickles on 9350 7199 and he will help attempt to help you.
Kind regards
The Rating Committee
