LLSC PY Adjustments

Overview

To ensure racing at Leigh and Lowton is as fair as possible, we use the RYA’s pyonline.org.uk website to calculate local PY amendments based on our racing results.  This is done on a regular basis and the process used is detailed below, along with the latest set of amendments.

April 2017 PY Update

The April 2017 local amendments to the RYA 2017 National PYs are as follows. This revison expands the races taken into account to include those upto December 2016, and apply from the start of April:

  • Enterprise 1113 (National PY 1113 LLSC adjustment= 0)
  • Laser 1082 (National PY 1097 LLSC adjustment= -15)
  • Laser 4.7 1201 (National PY 1200 LLSC adjustment= 1)
  • Laser Radial 1122 (National PY 1139 LLSC adjustment= -17)
  • Miracle 1192 (National PY 1210 LLSC adjustment= -18)
  • National 12 1066 (National PY 1064 LLSC adjustment= 2)
  • Optimist 1646 (National PY 1665 LLSC adjustment= -19)
  • Phantom 1014 (National PY 999 LLSC adjustment= 15)
  • RS 100 10.2 981 (National PY 978 LLSC adjustment= 3)
  • RS 200 1040 (National PY 1047 LLSC adjustment= -7)
  • RS 300 971 (National PY 973 LLSC adjustment= -2)
  • RS 400 940 (National PY 942 LLSC adjustment= -2)
  • RS Feva XL 1222 (National PY 1240 LLSC adjustment= -18)
  • Solo 1153 (National PY 1143 LLSC adjustment= 10)
  • Solution 1094 (National PY 1087 LLSC adjustment= 7)
  • Streaker 1142 (National PY 1132 LLSC adjustment= 10)
  • Supernova 1072 (National PY 1075 LLSC adjustment= -3)
  • Topper 1333 (National PY 1347 LLSC adjustment= -14)

November 2016 PY Update

The November 2016 local amendments to the RYA 2016 National PYs are as follows. This revison expands the races taken into account to include those between March and November 2016, and apply from the start of the 2016 Revett series:

  • Enterprise 1113 (National PY 1113 LLSC adjustment= 0)
  • Laser 1082 (National PY 1095 LLSC adjustment= -13)
  • Laser 4.7 1197 (National PY 1195 LLSC adjustment= 2)
  • Laser Radial 1119 (National PY 1136 LLSC adjustment= -17)
  • Miracle 1192 (National PY 1210 LLSC adjustment= -18)
  • National 12 1066 (National PY 1064 LLSC adjustment= 2)
  • Optimist 1646 (National PY 1665 LLSC adjustment= -19)
  • Phantom 1010 (National PY 995 LLSC adjustment= 15)
  • RS 100 10.2 981 (National PY 978 LLSC adjustment= 3)
  • RS 200 1040 (National PY 1047 LLSC adjustment= -7)
  • RS 300 972 (National PY 979 LLSC adjustment= -7)
  • RS 400 940 (National PY 943 LLSC adjustment= -3)
  • RS Feva XL 1221 (National PY 1235 LLSC adjustment= -14)
  • Solo 1153 (National PY 1140 LLSC adjustment= 13)
  • Solution 1095 (National PY 1090 LLSC adjustment= 5)
  • Streaker 1145 (National PY 1137 LLSC adjustment= 8)
  • Supernova 1072 (National PY 1075 LLSC adjustment= -3)
  • Topper 1333 (National PY 1341 LLSC adjustment= -8)

March 2016 PY Update

The RYA’s 2016 Portsmouth Yardsticks are available here

These are used for handicap racing at Leigh and Lowton, from 27th March 2016, with the following local
amendments which were calculated using the process detailed below.

  • Enterprise 1111 (National PY 1113 LLSC adjustment= -2)
  • Laser 1081 (National PY 1095 LLSC adjustment= -14)
  • Laser Radial 1119 (National PY 1136 LLSC adjustment= -17)
  • Miracle 1192 (National PY 1210 LLSC adjustment= -18)
  • National 12 1066 (National PY 1064 LLSC adjustment= 2)
  • Optimist 1647 (National PY 1665 LLSC adjustment= -18)
  • Phantom 1010 (National PY 995 LLSC adjustment= 15)
  • RS 100 10.2 981 (National PY 978 LLSC adjustment= 3)
  • RS 200 1040 (National PY 1047 LLSC adjustment= -7)
  • RS 300 972 (National PY 979 LLSC adjustment= -7)
  • RS 400 940 (National PY 943 LLSC adjustment= -3)
  • RS Feva XL 1229 (National PY 1235 LLSC adjustment= -6)
  • Solo 1152 (National PY 1140 LLSC adjustment= 12)
  • Solution 1094 (National PY 1090 LLSC adjustment= 4)
  • Streaker 1143 (National PY 1137 LLSC adjustment= 6)
  • Supernova 1073 (National PY 1075 LLSC adjustment= -2)
  • Topper 1333 (National PY 1341 LLSC adjustment= -8)
  • X1 900 (no National PY available)

2014/2015

Amendments to the local PYs were made in 2014 and 2015, but the details are not recorded here.

 

Process

Race data from our various handicap series from 2007 onwards is regularly submitted to the RYA website and their systems analyse the data and produce suggested PNs for classes at L&LSC. Basically, the RYA compute the average corrected time for a race and then for each class within it. This shows what change in each class handicap would be needed for their average corrected times to all be the same. Poor performers(outside 20%) are automatically excluded before class handicaps are computed by the RYA. This is intended to prevent undue influence from those who were late to the start, having a really bad day or simply new to the sport or the boat. Movements in class PNs are weighted so that a small number of results for any class do not have an undue influence compared to those with large numbers of results.

They have also give a confidence level. ‘Confidence Factor (c.f.)’ refers to the stability of the number – not its accuracy. Confidence in the stability of PNs obviously rises as more race data is input. We decided to recognise the likelihood of increasing confidence, and so the Sailing Committee agreed that the changes recommended by the RYA for L&LSC will be ‘damped’ by applying a % adjustment. Depending on the confidence level the % of any change applied will be as follows, upto a maximum variation from the national PYs of +/- 1.5%

0.0 c.f. = 0 % RYA Number to be used,
0.1 c.f. = 20%,
0.2 c.f. = 40%,
0.3 c.f. = 60%,
0.4 c.f. = 80%,
0.5 c.f. = 100%

Some classes have a lower PY and some a higher PY as a result.

Please contact the Sailing Manager if you require more information.