GWS opened up a gap to Collingwood on both MoSSBODS and MoSHBODS this week after its 73-point and 18 Scoring Shot victory over the Suns, and the Pies’ 4-point and 4 Scoring Shot loss to Fremantle.

MoSHPlay tipped eight winners this week, including the Roos’ upset win over the Tigers, to restore its one tip lead at the head of the Head-to-Head Tipsters Leaderboard. Its record is now 66 from 99 (67%). There were seven successful favourites, which helped the remaining Tipsters score 6 or 7 from 9 themselves, and left the all-Tipster average for the round at 6.9 from 9.

This week’s biggest differences between MoSHPlay and MoSHBODS are, for now, the following:

• Difference 19 points: Giants v Suns (MoSHPlay Giants by 68; MoSHBODS Giants by 49)

• Difference 12 points: Roos v Tigers (MoSHPlay Roos by 1; MoSHBODS Tigers by 11)

• Difference 12 points: Pies v Dockers (MoSHPlay Pies by 45; MoSHBODS Pies by 33)

• Difference 10 points: Dons v Blues (MoSHPlay Dons by 36; MoSHBODS Dons by 26)

Note that MoSHPlay and MoSHBODS are tipping the same winner in every game except North Melbourne v Richmond (though late changes may alter this).

This week sees seven of the contests with double-digit expected margins, and six with margins greater than twenty points, which has resulted in the first round of the season where the average expected margin exceeds four goals. It’s come in at 24.3 points per game.

This week, the MoS twins find themselves again broadly in synch with the bookmakers, and forecasting an average team score of just over 80 points per game.

GWS did enough this week to retain its number 1 ranking on MoSSBODS and MoSHBODS, gaining Ratings Points on both Systems while the 2nd-placed Collingwood kept the same Rating on MoSSBODS and fell slightly on MoSHBODS. Geelong performed similarly to Collingwood across the two Systems and remains 3rd on both.

Seven favourites were victorious this week, so head-to-head tipping results were generally good, though none of the MoS Head-to-Head Tipsters managed better than seven from nine. The RSMP twins were two of those that bagged seven which, in RSMP_Simple’s case, was enough to drag it into equal leadership with a slightly out of form MoSHPlay_Marg who bagged only five.

This week’s biggest differences between MoSHPlay and MoSHBODS are, for now, the following:

• Difference 14 points: Tigers v Dons (MoSHPlay Dons by 5; MoSHBODS Tigers by 9)

• Difference 12 points: Suns v Cats (MoSHPlay Cats by 40; MoSHBODS Cats by 28)

• Difference 10 points: Dogs v Roos (MoSHPlay Dogs by 17; MoSHBODS Dogs by 7)

• Difference 8 points: Swans v Pies (MoSHPlay Pies by 27; MoSHBODS Pies by 19)

• Difference 8 points: Hawks v Power (MoSHPlay Hawks by 0.1; MoSHBODS Power by 8)

• Difference 7 points: Dees v Giants (MoSHPlay Giants by 22; MoSHBODS Giants by 15)

• Difference 7 points: Saints v Blues (MoSHPlay Saints by 15; MoSHBODS Saints by 22)

Note that MoSHPlay and MoSHBODS are tipping the same winner in every game except Hawthorn v Port Adelaide (though late changes may alter this).

This week, it’s almost as if the bookmakers took MoSSBODS’ totals forecasts and randomly perturbed them slightly to come up with their own opinions. Their average expected totals are within one point of MoSSBODS’ (and not much more different from MoSHBODS’).

Seven of this week’s nine games are expected to be decided by less than three goals, and a eighth by only about three-and-a-half goals, leaving the Suns v Cats game to do all the heavy lifting of dragging up the all-game average.

Just how much effect a serious blowout victory should have on a team’s rating is an interesting thing to ponder, but my historical optimisation efforts - at least for MoSSBODS and MoSHBODS - suggest that putting a cap on the size of the adjustment is suboptimal.

I thought last week’s 18.5 all-Predictor average mean absolute error (MAE) would take some time to beat, but it took only seven days. This week’s average was 16.5 points per game per Predictor.

This week’s biggest differences between MoSHPlay and MoSHBODS are, for now, the following:

• Difference 19 points: Pies v Saints (MoSHPlay Pies by 49; MoSHBODS Pies by 30)

• Difference 9 points: Roos v Swans (MoSHPlay Roos by 12; MoSHBODS Roos by 21)

• Difference 8 points: Dons v Dockers (MoSHPlay Dons by 24; MoSHBODS Dons by 17)

• Difference 7 points: Power v Suns (MoSHPlay Power by 44; MoSHBODS Power by 51)

• Difference 7 points: Tigers v Hawks (MoSHPlay Tigers by 2; MoSHBODS Tigers by 9)

For the first time this season, the MoS twins’ totals forecasts are, in aggregate, near parity with the bookmakers’. Their average expected total is, again, 162, and the bookmakers’ is 162 to 163.

This week we have nine home team favourites - and considerable favourites at that in most cases.

Collingwood, who still sit atop both MoS Rating Systems, now have a 2 Scoring Shot (or about 7.3 points if we assume a 53% conversion rate) lead over Geelong on MoSSBODS, and a 3.3 points lead over Geelong on MoSHBODS. GWS fill 3rd place under both Systems, fractionally behind Geelong on MoSSBODS, and just over 2 points behind on MoSHBODS.

As expected with the higher levels of disagreement this week, there was quite a spread of scores across the Head-to-Head Tipsters, ranging from 3 out of 9s for C_Marg, Home Sweet Home, and Consult the Ladder, to 7 out of 9s for the RSMP twins and Bookie Knows Best.

This week’s biggest differences between MoSHPlay and MoSHBODS are, for now, the following:

• Difference 14 points: Blues v Pies (MoSHPlay Pies by 48; MoSHBODS Pies by 34)

• Difference 12 points: Dockers v Tigers (MoSHPlay Dockers by 9; MoSHBODS Tigers by 3)

• Difference 11 points: Saints v Eagles (MoSHPlay Eagles by 2; MoSHBODS Saints by 9)

• Difference 9 points: Power v Crows (MoSHPlay Crows by 5; MoSHBODS Power by 4)

Note that this includes three games where MoSHPlay and MoSHBODS are tipping different winners.

The MoS twins are, once again, slightly more pessimistic than the bookmakers about the return to high-scoring contests, but at least the pessimism discount now seems to be locked in at around half a goal. This week, their average expected total is 162 to the bookmakers’ 164 to 165.

Monday morning was what I can only describe as an odd period on the markets. By the time I ventured in to see where things were at around 9 or 10am, four of the line markets had moved from where they started, one by as much as the equivalent of half a goal or so (it was at $1.75 / $2.05).