Speed Performance Ratings (SPR) can be described as an indicator of relative
(recent) ability. An understanding of SPR involves much more than a comparison
of overall race times.
The DNA of SPR
Whilst the following individual factors aren't in isolation anything
new, combined they hold the key towards a better understanding of the value of
knowing what a SPR is, so that you can more accurately peg a horses ability.
The four important factors are:
1. Early speed;
2. Sectional times;
3. Peak speed; and
4. Overall race time
SPR in isolation are:
·
not designed to reliably predict the likely outcome of
a race; and
·
not designed as an indicator of likely market prices/rank.
It is important to note that in some races, the predictive SPR will, for
the most part be inaccurate when measured against market expectations and/or
actual results. These inaccuracies can be either positive or negative and it is
for this reason, that SPR should not be taken at face value or considered in
isolation as an indicator of the likely outcome of a race. Rather, with a
thorough understanding of the DNA of SPR and its components, SPR can be
considered as a unique method of comparing race horses, many of which have not
previously competed against each other or raced at the same tracks and/or
distances.
SPR fall into two categories:
·
Historical
(assigned to each historical run); or
·
Predictive (an SPR
derived from a historical run using a unique algorithm that is then used to
compare against other competitors)
Historical SPR
The race winner’s time is adjusted using a complex algorithm for a range
of factors including track condition and other proprietary factors before being
compared with a ‘par’ time for that track and distance.
The SPR calculated for each historical run is a numerical value that is
firstly assigned to the winner of each race. For the purposes of this article
and for Axis software users, consider 2 rating points as one length.
For those individuals that create, or for organizations that supply
ratings, that are derived from the standard publicly available form (other
than R2W), a Rating of 104 for a race winner could indicate any one of the
following:
·
the winner ran a
time that (when adjusted) was equal to or faster than the par time;
·
the official
time was incorrect;
·
the distance of
the race was shorter than the official distance; or
·
the prevailing
conditions caused faster times (e.g. wind factor, track surface).
Conversely, a Rating of 86 for a race winner could indicate any one of
the following:
·
the winner ran
only as fast as it needed to (to win the race)
·
the winner ran a
very slow time (relative to ‘par’ and/or other races on the day);
·
the official
time was incorrect;
·
the distance of
the race was longer than the official distance; or
·
the prevailing
conditions caused slow times (e.g. wind factor, track surface).
In summary the Axis SPR assigned to each historical run can be
considered an accurate and comparative measurement of how fast a horse ran
(relative to par) on that occasion after adjustments have been made.
SPR Scale
Fast performances = high SPR
Slow performances = low SPR
The SPR for all other runners in a race (other than the winner) is
derived from the rating assigned to the race winner before being downwardly
adjusted for beaten margins.
Logically because horses run at a faster speed over 1000m than they do
at 2400m, the incremental adjustment is less as the distance increases. Again I
suggest, for the purposes of explanation, that you can assume an adjustment of 2
rating points as being equal to 1 length.
E.g. If a race winner gets an SPR of 100, a horse beaten 2 lengths would
get an SPR of ~96.
Predictive SPR
Within Axis, a complex algorithm selects a historical SPR that is then
assigned as a run that is representative of each horse’s current ability and
likely fitness level. That run is called the qualifying run (QR).
The R2W SPR algorithm encompasses the following assumptions:
·
high ratings
can’t be produced by unfit horses;
·
recent form is far
more reliable as an indicator of current ability and likely fitness that older
form;
·
generally
speaking, trainers will place their horses to the best advantage;
·
horses that
perform well when resuming from spells will generally continue to do so up to
the age of around five; and
·
importantly a
good rating can be discarded as an indicator of current ability and fitness
after approximately 42 days.
Having selected an appropriate QR, the SPR algorithm then assigns that
numerical value to each runner as a Base SPR. This is then interrogated by the
R2W computer before determining whether any adjustment is warranted. Once this
process is complete the predictive SPR is displayed in the field view of Axis.
Caution needs to be applied
to races that are run in fast times
As has been explained above, races run in fast times (relative to par
times) produce high ratings. However, it does not always follow that all horses
that run a fast time, and therefore generating a high SPR will subsequently
‘run up’ to that performance at their next race start. However, it is true that
horses that can run genuinely fast times, particularly in good class races,
have more ability than other horses they may race against in future.
Why R2W SPR are more
accurate than other commercially available ratings
Without going into too much detail and to preserve our unique IP, R2W
SPR are adjusted for the many errors that exist in overall race times,
sectionals, distances, track conditions, class of race etc. We outsource to a
private organisation that caters to our specific needs and those of some of
Australia's biggest and most successful punters. As a guide it is fair and accurate
to suggest that more than 90% of official race and sectional times reordered in
Australia are incorrect and contain errors that are often significant. Being
able to deliver SPR that are adjusted for these errors is one fundamental
reason as to why we and our clients are able to maintain and enjoy a profitable
betting edge. No other software provider that we are aware of provides the
total solution to this problem, that is for ALL TAB races Australia wide.
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