Ratings and sectionals explained
By Timeform — published Thursday 13 August, 2020 at 15:49
Timeform's guide to ratings and sectionals and how best to use them to your advantage.
Greyhound racing is a sport defined by time. Listen to any discussions on RPGTV nights and the first thing you will hear when an upcoming race is discussed is which greyhounds have the best ‘early’ or sectionals, and so, in theory, the best chance of leading around the first bend. After all, the greyhound that leads in races over four bends wins around 35% of the time - and considerably more at some tracks.
And when a greyhound wins a race, it is not the distance it has won by or the company it has beaten that determines whether it will go up in grade or not next time out but its winning time.
As such, time is basis for evaluating the merit of any greyhound performance and the method we use is not dissimilar to the one we use to return timefigures for horseracing.
In other words, for each meeting we compare ‘expected time’ to our calculated final time (adjusted for trouble in running) and then return a going allowance for each race after a couple of other factors into account.
We should mention here that ‘expected time’ is the same thing as ‘expected performance’ – the two are interchangeable. A performance rating relates exclusively to the time for the distance that prompts it. So, for example, over 483m at Doncaster a rating of 100 might equal a time of 29.69 seconds. Expected times are calculated from the greyhound’s previous eight races at the number of bends it is running at today (so ratings recorded at sprint trips are not used in four-bend races) or a combination of races and trials if it hasn’t had eight races.
We need to calculate a separate expected time for each track and distance because, for all greyhound tracks might look similar, they are all different. A top Open racer might get under 28.50 seconds for the 500m trip at Sheffield but the same greyhound wouldn’t get within a second (or approximately 13 lengths, a length being somewhere between 0.07 and 0.08 of a second) of that time over Newcastle’s 500m trip. All expected times for each track are derived from the time we would expect a greyhound rated 100 to achieve at the distance on ‘normal’ going (think of ‘good’ going on the Flat, a surface that neither speeds up nor slows down expected final times). As with horseracing, the surface has a big impact on final times. Wet and heavy surfaces in winter slow down times considerably compared to slicker surfaces in summer.
One advantage of having ratings that are interchangeable with track-specific times is that it allows us to adhere closely to the 0-140 scale in horseracing that many who follow both sports are already familiar with. A horse that is rated 60 on the Flat is a modest handicapper, while one that is rated 120 is a decent Group-class performer. The same applies to greyhounds; one rated 60 would generally be running in the lower grades, while one rated 120 or higher ought to be cleaning up on the Open circuit.
Open racers apart, most greyhounds are attached to one stadium and so different tracks have different kennel strengths. A regular A1 winner at Sunderland would find itself well out of its depth in A1 company at Hove. It’s important to remember that while ratings are interchangeable across tracks, grades are not. An A1 winner at Sunderland might only be worth 80, and might need to be rated 105 to score in the same grade at Hove.
So, the preliminary going allowance is effectively an expression of the difference in expected performance (or time) compared to actual performance (or time) adjusted pro rata dependent upon race distance after trouble in running has been accounted for. We know from having a database of millions of performances the effect a bump at the first bend over 380m at Crayford has on expected final time. It is not the same as a bump at the first bend over 480m and the two are treated differently.
After that, the final allowance is arrived at after adjusting for two things, so long as at least one of them is present - any inside or outside bias on the day, or differences between the early and late part of the meeting.
If wide runners on a card constantly run faster than their expected times in clean-run races, and the inside traps constantly run slower, then there is a good chance the outside was running faster. It makes sense to adjust times for this, as it does for parts of the meeting where the surface speed differed much more than would have been expected.
Once the definitive final allowance is arrived at, the race ratings for each greyhound can be calculated. Greyhounds behind the winner also have their ratings adjusted if they suffer trouble in running, so it’s not unusual to see greyhounds that finished second or third rated higher than the winner.
For each distance where a sectional time is recorded, we also return sectional performance ratings using essentially the same criteria described above (in other words, a 100-rated sectional performance at one track ought to be the same as a 100-rated performance at another). As with overall times, sectional times are adjusted (proportionately) for the going allowance, otherwise it would not always be apparent that the reason any sectional time was slow was simply because the surface was slow.
Going allowances are expressed either positively or negatively. A greyhound that wins in 29.36, for example, on ground that we have rated 0.18 (or 0.18 fast) will have its final time adjusted to 29.18 and be credited with the rating equivalent to that track at that distance. These final times or performance ratings (as well as sectional times and ratings) then feed into the expected sectional and final times for the greyhound’s next race and the process starts all over again.







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