Gambling
odds and probabilities by prices
Decimal odds (like the Betfair and TAB
odds are expressed) are a simple reflection of the return you will
receive for each single unit placed.
For example, let's say a TAB is showing
odds of 1.65 for a horse to win. This means that for every 1.00 you
bet on that particular outcome, you will receive a profit of 0.65
should it salute.
To convert these odds to their respective implied
probabilities we make a simple calculation.
Calculating decimal odds
So for example, our odds of 1.65.
Implied probability = 1 / 1.65
Implied probability = 0.606
Multiplied then by 100 to express as
an implied probability percentage of 60.6%.
So a table of decimal odds / implied
probability would read as:
ODDS |
IMPLIED
CHANCE |
1.00 |
100% |
1.10 |
90.9% |
1.20 |
80.3% |
1.30 |
77.0% |
1.40 |
71.4% |
1.50 |
66.7% |
1.60 |
62.5% |
1.70 |
58.8% |
1.80 |
55.6% |
1.90 |
52.6% |
2.00 |
50.0% |
2.10 |
47.6% |
2.20 |
45.5% |
2.30 |
43.5% |
2.40 |
41.7% |
2.50 |
40.0% |
2.60 |
38.5% |
2.70 |
37.0% |
2.80 |
35.7% |
2.90 |
34.5% |
3.00 |
33.3% |
3.10 |
32.3% |
3.20 |
31.3% |
3.30 |
30.3% |
3.40 |
29.4% |
3.50 |
28.6% |
3.60 |
27.8% |
3.70 |
27.0% |
3.80 |
26.3% |
3.90 |
25.6% |
4.00 |
25.0% |
4.10 |
24.4% |
4.20 |
23.8% |
4.30 |
23.3% |
4.40 |
22.7% |
4.50 |
22.2% |
4.60 |
21.7% |
4.70 |
21.3% |
4.80 |
20.8% |
4.90 |
20.4% |
5.00 |
20.0% |
5.10 |
19.6% |
5.20 |
19.2% |
5.30 |
18.9% |
5.40 |
18.5% |
5.50 |
18.2% |
5.60 |
17.9% |
5.70 |
17.5% |
5.80 |
17.2% |
5.90 |
16.9% |
6.00 |
16.7% |
Now these are
"pure" odds and take no account of the TAB or Betfair "takeouts"
so while you may think you are getting the correct mathematical odds
are you have rated the chances, you will in fact be taking under the
true odds without taking the "house percentage" in to account.
Hence the theory
that if, over the long stretch if time, your method of selection returns
40% winners, by taking NO LESS than $3 (33.3% chance of winning) and
taking in to account the takeouts by Betfair, the theory is that using
a staking progression plan you may come out in front of the game.
The key word here
is THEORY..........
Horse
racing systems and research