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2012 Round 20 Results : Near Enough Isn't Good Enough

As if taking a leaf from the Australian Olympians, Combo_NN2 finished with the SuperMargin equivalent of Silver in five contests this week, selecting the bucket next to the winner on each occasion (and failing to record a PB in any of them). Three of the Silvers came in events where the Margin Fund had a wager and contributed to the Fund's 0 and 7 record for the round, knocking 17.5c from its value.

The Head-to-Head Fund fared only a little better, landing its smaller but losing its larger wager to finish down 6.4c on the round, while the Line Fund also struggled, collecting only twice from its five wagers, dropping 6c. In total, Overall Portfolios fell by another 8.4c this week, making the total loss for the season now just over 21c. To labour the Olympics-flavoured metaphors for a moment longer, Profitability has put on a late surge and we're now at risk of losing sight of it.

Our Head-to-Head Tipsters, however, for the most part continued to flourish. Eight favourites won, resulting in a number of Tipsters recording eight correct selections and dragging the all-Tipster average up to 6.8 from 9 for the week. The worst performances of the round were the 4 from 9s attributable to Easily Impressed I and Follow The Streak. One of the Tipsters to score 8, H2H_Unadj_10, remains our leader, now on 134 of 171 (78%) and still one tip ahead of the following pack. That pack thinned a little this weekend but still comprises eight tipsters all on 133.

Our Margin Predictors were all especially accurate this week and produced an all-Predictor MAPE of just 18.30 points per game, the third-lowest this season. Best was Bookie_3's 14.20 points per game, which lowered its season-long MAPE to 29.26 points per game and extended its lead over Combo_7 (16.59 this week; 29.87 for the season) and Bookie_9 (16.97 this week; 30.00 for the season). Combo_NN_1 registered the round's worst MAPE, but still turned in a creditable 23.29 points per game performance.

Accurate margin prediction translated into exceptional SuperMargin performances for a number of Predictors. Bookie_3, for example, selected the correct bucket in three games and was in error by a single bucket in one more; Win_3 and Win_7 also selected the correct bucket in three games but were off-by-one in another four and three games respectively; and Combo_NN_2, as already noted, selected the bucket adjacent to the correct one in five contests.

Still though only the four Head-to-Head Predictors boast profitable season-long SuperMargin wagering records.

The line betting performances of the Margin Predictors were, as a group, slightly less impressive, though the all-Predictor average of 4.6 from 9 was marginally better-than-chance. Win_3 and Win_7, whose impressive SuperMargin records were noted above, helped to raise this average by correctly predicted eight of the nine line outcomes.

All five Head-to-Head Probability Predictors recorded positive probability scores for the round, best amongst them WinPred, which extended its lead over ProPred in so doing, but which still trails the TAB Bookmaker and both H2H variants by some margin.

Negative probability scoring was once again the fate of the Line Fund algorithm.