NRL S2016 R07 predictions and staking guide
maxwellAI
12 April 2016
Summary
After a stellar round 6 (7/8 predictions correct) and a win on our first bet, its time to take a look at the round 7 tips and staking recommendations.
This week there are four games which disagree with the bookmaker (games 1, 3, 6 and 8); and unlike round 6 which only identified one game to stake on, this round three games have been identified (games 4, 7 & 8)!
Specifically games recommended to stake on are:
game 4 - Canterbury Bulldogs to win against New Zealand Warriors while Home with a probability of 70.4% (currently paying $1.92)
game 7 - Melbourne Storm to win against Wests Tigers while Away with a probability of 67.4% (currently paying $1.70)
game 8 - Sydney Roosters to win against Penrith Panthers with a probability of 69.5% while Home (currently paying $2.20)
Predictions for games 4 and 8 are at long odds and represent the best ‘value’ bets.
The prediction for game 7 agrees with the bookmaker (Melbourne to win) and represents a marginally good bet. At time of writing Bulldogs and New Zealand were at even odds (1.92 each).
Ok, so lets take a detailed look at the predictions for this week and how they compare to the bookmaker predictions:
Predictions
| game_no | tip_text | perceived_prob | bookie_prob | bookie_odds | agree_with_bookie |
|---|---|---|---|---|---|
| 1 | Manly Sea Eagles to win against Parramatta Eels while Home | 0.560 | 0.488 | 2.05 | N |
| 2 | North Queensland Cowboys to win against South Sydney Rabbitohs while Home | 0.738 | 0.769 | 1.30 | Y |
| 3 | St George Illawarra Dragons to win against Gold Coast Titans while Away | 0.511 | 0.435 | 2.30 | N |
| 4 | Canterbury Bulldogs to win against New Zealand Warriors while Home | 0.704 | 0.521 | 1.92 | Y |
| 5 | Brisbane Broncos to win against Newcastle Knights while Home | 0.860 | 0.893 | 1.12 | Y |
| 6 | Cronulla Sharks to win against Canberra Raiders while Away | 0.548 | 0.465 | 2.15 | N |
| 7 | Melbourne Storm to win against Wests Tigers while Away | 0.674 | 0.588 | 1.70 | Y |
| 8 | Sydney Roosters to win against Penrith Panthers while Home | 0.695 | 0.455 | 2.20 | N |
NB Bookmaker odds (taken from www.Sportsbet.com.au) as at 13-Apr-2016
Prediction observations
We observe four games which disagree with the bookmaker (games 1, 3, 6 and 8). The majority of games which agree with the bookmaker have relatively close probabilities with the exeption of game 4 (Bulldogs vs Warriors)
Games 1,3 and 6 have marginal predictions (<56% chance of team to win)
Games 4 has a very wide difference between the models probability and the bookmakers probability (70.04% vs 52.1% respective). In addition game 8 has a similarly wide difference (69.5% vs 45.5%)
Stake recommendation/s
Recommended bets are those with a perceived probability of > 0.66 and a positive expected return. Also recall that in order to make a long term profit our models precision must be greater than the overall average implied probability. Our best model has a 72% precision to date, while our ‘as posted’ model has an average precision of 61.6%. Taking the conservative 61.6% as the precision of our model, this means we don’t want to be placing bets on odds less than 1.62 (1/0.616). That makes our last bet on the Cowboys (at 1.69) a pretty marginal bet if we assume this precision. Considering these restrictions to optimise our chances of winning, lets review the stake recommendaitons below. I have also included a potential profit (from a $50 bet) assuming you back the prediction. Profit is determined by the formula: stake*odds - stake.
| game_no | tip_text | perceived_prob | bookie_odds | expected_return | recommend_stake | potential_profit |
|---|---|---|---|---|---|---|
| 1 | Manly Sea Eagles to win against Parramatta Eels while Home | 0.560 | 2.05 | 0.149 | N | 52.5 |
| 2 | North Queensland Cowboys to win against South Sydney Rabbitohs while Home | 0.738 | 1.30 | -0.041 | N | 15.0 |
| 3 | St George Illawarra Dragons to win against Gold Coast Titans while Away | 0.511 | 2.30 | 0.175 | N | 65.0 |
| 4 | Canterbury Bulldogs to win against New Zealand Warriors while Home | 0.704 | 1.92 | 0.351 | Y | 46.0 |
| 5 | Brisbane Broncos to win against Newcastle Knights while Home | 0.860 | 1.12 | -0.037 | N | 6.0 |
| 6 | Cronulla Sharks to win against Canberra Raiders while Away | 0.548 | 2.15 | 0.178 | N | 57.5 |
| 7 | Melbourne Storm to win against Wests Tigers while Away | 0.674 | 1.70 | 0.147 | Y | 35.0 |
| 8 | Sydney Roosters to win against Penrith Panthers while Home | 0.695 | 2.20 | 0.529 | Y | 60.0 |
Three games (4, 7 & 8) are identified as ‘good value bets’ which satisfy the staking requirments. Each of these games have a percieved probaility of >0.66 and the odds of each game are >1.62. For each game we will bet 5% of the bank. After round 6 the current bank is $2,276 therefore we will place $114 on the first match for a potential profit of $125.40
NB bank and stake amounts are rounded to whole numbers
Conclude
Lets hope we have another good round. Good luck contributors!