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</o:shapelayout></xml><![endif]--></head><body lang=EN-AU link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>Saw this in Ausrace Archives:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Hi,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>I am using a set of jockey ratings that have been calculated over a 12 mnth history.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Naturally there are potentially some inaccuracies with jockeys currently out of form or others recently improved and not commanding a high rating.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>My question is has anyone ever done any analysis to determine the optimum period over which to calculate the rating and how often to update it ?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>Thanks in advance.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Peter<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>The " optimum period over which to calculate the rating" is something that I have never heard a definitive answer to, because there is not, imo, one. I've tested various periods of time, various number of rides, which to be disregarded as "outliers" …. and have never satisfied myself as to "the optimum"; maybe I'm just a hard taskmaster.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>But " how often to update it" is easy - ideally after every race, if impractical, then as often as possible. When ConK fielded, he used to keep horses ridden by a jockey who rode the last winner short. I've not seen published research into the Impact Value of such jockeys (I've done it, "of course") but there has been published research in other sports, such as basketballers who missed/got their last penalty shot. Without doing the research, or even knowing much about basketball, common sense tells me that someone who goaled last shot has a better chance next time than if he missed (referring to particular players, not lumping them all together when there are varying levels of ability to be considered) - pot a hard shot, walk tall, confidence up; miss a gimmee, head down, shoulders sagging, confidence shot (OK, a bit of an exaggeration, but the point is, I hope, taken).<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>I've seen it at football - take a screamer, kick a 60m goal, and you're 7' tall, while your opponent shrinks; miss a sitter from 15m and you feel 5' short, and in either case play accordingly. Why would it not be the same with a jockey who has just ridden a well-judged ride to land a winner compared to after he's ridden a stinker? Of course people are different, but that can be taken into some account by analysing individual jockeys.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>To today's Bookmaker Joke - I backed MV 1/2 at 71.0 for MBL max with Centrebet "Take Us On", they treated me with deserved lack of respect and wind it to 126.0, but wouldn't take any more from me. Is there some sense to that MO that I'm missing?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'>LBL<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial","sans-serif"'><o:p> </o:p></span></p></div></body></html>