Dumb Q about football money lines

ZeRo C@iDa* · 09-28-07, 03:35 PM

Originally posted by atakdog

Dumb question, I suppose:

Why is playing the money line so unpopular (at least, I gather it is)? Who plays the money line, and under what sort of circumstances does it make sense?

I have a sense it may simply be tradition, in which case I would think there might be value there...

it was last Sundays ML on Giants that saved My @$s...

SBR_John · 09-28-07, 04:58 PM

I love ML plays in the NFL and NBA. Not so much in NCAA. I think ML bets are smart bets in the NFL as long as your taking the dog.

Scratch · 09-28-07, 09:56 PM

I think betting the faves on the ML is usually more risk than the reward is worth. However, I do remember reading in the paper about a wealthy businessman risking 800,000 to win 1 million on the 49ers ML over SD in the superbowl 94 season. We all know what an ass whippin that was.

Scratch · 09-28-07, 10:09 PM

I should clarify he had to front the 800,000. He only profited 200,000 on his risk.

Cyclone · 09-28-07, 10:25 PM

I have read that, instead of betting on an underdog of three points or less, you are probably better off betting on the moneyline. If the final score is really that close, your team has a decent chance of winning outright.

rm18 · 09-28-07, 11:56 PM

Originally posted by Scratch

I should clarify he had to front the 800,000. He only profited 200,000 on his risk.

You would have had had to lay 15 dollars to win one on that game at least

Ganchrow · 09-29-07, 11:58 AM

My answer to this question would be similar to the answer I gave to a related question on the comparison between baseball run and money lines.

I'd raise two issues:

Do we have reason to suspect that bookmakers systematically shade their lines in one direction or another (i.e., towards the fave or the dog)? To be perfectly honest, because I don't really bet football, and due to the scarcity of historical football money line data, I can't say I've looked too deeply into an answer to this question. Nevertheless, in Fixed Odds Sports Betting: Statistical Forecasting and Risk Management, Joseph Buchdahl presents a surfeit of compelling theoretical evidence (especially in the cases of rather lopsided markets) why bookmakers might choose to shade their money lines as to present better value for the favorite bettors.

Furthermore, there's certainly evidence to suggest that many so-called "square" bookmakers have (at least in the past) shaded their spreads a not inconsequential amount so as to favor the bettor taking the underdog.

Considering this all together, this tends to implies that there's probably no systematic bias which would work to favor money line dog relative to the dog spread on the same game.
To what extent and under what circumstances does betting market microstructure favor either spread or money line wagers? This is the issue I primarily addressed in link to the run line thread above. The conclusions I drew with respect to baseball wagers are valid in this case as well:

As long as one have no specific reason to believe that there exists a pricing bias where the spread and money line are mispriced relative to one another then in general, for a given zero-vig edge, one should look to bet money line favorites and spread underdogs.

As I wrote in the previously mentioned run line thread, "This ... will hold little weight for those that subscribe to the lottery mentality of sports betting, but for advantage bettors (whom we'd generally expect to avoid such ultimately detrimental staking strategies) it's clearly the superior option from the perspective of growth maximization and risk minimization."

(I will note, however, that this will naturally be less valid right above money line break points. For example, if a money line market breaks from 20c to 30c at -190/+160, then markets at exactly that level or slightly will naturally be inferior to market slightly lower than level.)

Let's look at tomorrow's (Sunday, Spetmebr 30, 2007) slate of NFL games at CRIS/Bookmaker. We'll compare the maximum possible expected growth (i.e., the E(G) associated with a full-Kelly bet) assuming a 7.5% edge at the no-vig (i.e., the "mid-market") price.
<STYLE> .GANCH { font-size: 9px; font-family: Verdana, Arial, Helvetica, sans-serif; } </STYLE> <table><TR><TD CLASS=GANCH>ROT</TD><TD CLASS=GANCH>DATE</TD><TD CLASS=GANCH>TEAMS</TD><TD CLASS=GANCH>SPREAD</TD><TD CLASS=GANCH>ML</TD><TD CLASS=GANCH>SPR WIN %</TD><TD CLASS=GANCH>ML WIN %</TD><TD CLASS=GANCH>SPR E(G)</TD><TD CLASS=GANCH>ML E(G)</TD><TD CLASS=GANCH>ML/SPR E(G)</TD></TR> <tr> <td align=center class=GANCH> 205 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> OAK </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> +190 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 35.58% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.0266% </td> <td align=center class=GANCH> 0.71 </td> </tr> <tr> <td align=center class=GANCH> 206 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> MIA </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> -230 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 71.92% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.1186% </td> <td align=center class=GANCH> 3.15 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 207 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> HOU </td> <td align=center class=GANCH> +100 </td> <td align=center class=GANCH> -140 </td> <td align=center class=GANCH> 51.41% </td> <td align=center class=GANCH> 60.42% </td> <td align=center class=GANCH> 0.0399% </td> <td align=center class=GANCH> 0.0900% </td> <td align=center class=GANCH> 2.25 </td> </tr> <tr> <td align=center class=GANCH> 208 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> ATL </td> <td align=center class=GANCH> -120 </td> <td align=center class=GANCH> +120 </td> <td align=center class=GANCH> 56.09% </td> <td align=center class=GANCH> 47.08% </td> <td align=center class=GANCH> 0.0480% </td> <td align=center class=GANCH> 0.0532% </td> <td align=center class=GANCH> 1.11 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 209 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> BAL </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> -215 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 71.00% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.1771% </td> <td align=center class=GANCH> 4.71 </td> </tr> <tr> <td align=center class=GANCH> 210 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> CLE </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> +185 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 36.50% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.0435% </td> <td align=center class=GANCH> 1.16 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 211 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> CHI </td> <td align=center class=GANCH> +105 </td> <td align=center class=GANCH> -145 </td> <td align=center class=GANCH> 50.26% </td> <td align=center class=GANCH> 61.39% </td> <td align=center class=GANCH> 0.0438% </td> <td align=center class=GANCH> 0.1019% </td> <td align=center class=GANCH> 2.33 </td> </tr> <tr> <td align=center class=GANCH> 212 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> DET </td> <td align=center class=GANCH> -125 </td> <td align=center class=GANCH> +125 </td> <td align=center class=GANCH> 57.24% </td> <td align=center class=GANCH> 46.11% </td> <td align=center class=GANCH> 0.0576% </td> <td align=center class=GANCH> 0.0557% </td> <td align=center class=GANCH> 0.97 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 213 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> GB </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> -130 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 58.34% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.0679% </td> <td align=center class=GANCH> 1.80 </td> </tr> <tr> <td align=center class=GANCH> 214 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> MIN </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> +110 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 49.16% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.0473% </td> <td align=center class=GANCH> 1.26 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 215 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> STL </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> +650 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 13.87% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.0124% </td> <td align=center class=GANCH> 0.33 </td> </tr> <tr> <td align=center class=GANCH> 216 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> DAL </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> -900 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 93.63% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.8324% </td> <td align=center class=GANCH> 22.13 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 217 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> NYJ </td> <td align=center class=GANCH> -125 </td> <td align=center class=GANCH> -190 </td> <td align=center class=GANCH> 57.24% </td> <td align=center class=GANCH> 67.74% </td> <td align=center class=GANCH> 0.0576% </td> <td align=center class=GANCH> 0.1102% </td> <td align=center class=GANCH> 1.91 </td> </tr> <tr> <td align=center class=GANCH> 218 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> BUF </td> <td align=center class=GANCH> +105 </td> <td align=center class=GANCH> +160 </td> <td align=center class=GANCH> 50.26% </td> <td align=center class=GANCH> 39.76% </td> <td align=center class=GANCH> 0.0438% </td> <td align=center class=GANCH> 0.0357% </td> <td align=center class=GANCH> 0.82 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 219 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> TBA </td> <td align=center class=GANCH> -125 </td> <td align=center class=GANCH> +130 </td> <td align=center class=GANCH> 57.24% </td> <td align=center class=GANCH> 45.17% </td> <td align=center class=GANCH> 0.0576% </td> <td align=center class=GANCH> 0.0580% </td> <td align=center class=GANCH> 1.01 </td> </tr> <tr> <td align=center class=GANCH> 220 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> CAR </td> <td align=center class=GANCH> +105 </td> <td align=center class=GANCH> -150 </td> <td align=center class=GANCH> 50.26% </td> <td align=center class=GANCH> 62.33% </td> <td align=center class=GANCH> 0.0438% </td> <td align=center class=GANCH> 0.1141% </td> <td align=center class=GANCH> 2.61 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 221 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> SEA </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> -135 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 59.40% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.0787% </td> <td align=center class=GANCH> 2.09 </td> </tr> <tr> <td align=center class=GANCH> 222 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> SF </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> +115 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 48.10% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.0504% </td> <td align=center class=GANCH> 1.34 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 223 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> PIT </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> -270 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 75.96% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.2317% </td> <td align=center class=GANCH> 6.16 </td> </tr> <tr> <td align=center class=GANCH> 224 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> ARZ </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> +230 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 31.54% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.0361% </td> <td align=center class=GANCH> 0.96 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 225 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> KC </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> +525 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 16.75% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.0208% </td> <td align=center class=GANCH> 0.55 </td> </tr> <tr> <td align=center class=GANCH> 226 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> SD </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> -650 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 90.75% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.7977% </td> <td align=center class=GANCH> 21.21 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 227 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> DEN </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> +450 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 19.01% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.0230% </td> <td align=center class=GANCH> 0.61 </td> </tr> <tr> <td align=center class=GANCH> 228 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> IND </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> -550 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 88.49% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.6231% </td> <td align=center class=GANCH> 16.56 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 229 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> PHI </td> <td align=center class=GANCH> +100 </td> <td align=center class=GANCH> -150 </td> <td align=center class=GANCH> 51.41% </td> <td align=center class=GANCH> 62.33% </td> <td align=center class=GANCH> 0.0399% </td> <td align=center class=GANCH> 0.1141% </td> <td align=center class=GANCH> 2.86 </td> </tr> <tr> <td align=center class=GANCH> 230 </td> <td align=center class=GANCH> 20070930 </td> <td align=center class=GANCH> NYG </td> <td align=center class=GANCH> -120 </td> <td align=center class=GANCH> +130 </td> <td align=center class=GANCH> 56.09% </td> <td align=center class=GANCH> 45.17% </td> <td align=center class=GANCH> 0.0480% </td> <td align=center class=GANCH> 0.0580% </td> <td align=center class=GANCH> 1.21 </td> </tr> <tr> <td align=center class=GANCH> </td> </tr> <tr> <td align=center class=GANCH> 231 </td> <td align=center class=GANCH> 20071001 </td> <td align=center class=GANCH> NE </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> -350 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 80.85% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.2826% </td> <td align=center class=GANCH> 7.51 </td> </tr> <tr> <td align=center class=GANCH> 232 </td> <td align=center class=GANCH> 20071001 </td> <td align=center class=GANCH> CIN </td> <td align=center class=GANCH> -110 </td> <td align=center class=GANCH> +290 </td> <td align=center class=GANCH> 53.75% </td> <td align=center class=GANCH> 26.65% </td> <td align=center class=GANCH> 0.0376% </td> <td align=center class=GANCH> 0.0266% </td> <td align=center class=GANCH> 0.71 </td> </tr> </table>
What we see without exception is that taking the money line favorite provides greater expected bankroll growth than the taking the corresponding spread. In the case of very large favorites, such as Dallas, San Diego, and Indianapolis, a full-Kelly money line bet (once again, assuming a 7.5% zero-vig edge) implies 22.13, 21.21, and 16.56 times as much expected bankroll growth as the corresponding bet on the spread.

Similarly when betting on the money line underdog, in most (but not all) cases a bet on the spread provides higher expected growth than a bet on the corresponding money line. Where this not the case this is due to the significantly lower vig on the higher magnitude money line.

atakdog · 09-29-07, 12:47 PM

My goodness; Thank you, Sir Ganch -- I have some digesting to do.

A related question, for you or anyone else: why would it be that often, when a book is taking unbalanced action in terms of number of bets (which data are easily available, in contrast to dollar amounts), the numbers of bets on the money line tends to be more balanced? This seems to be generally true (looking at the data available at SportsInsights), particularly for teams that are favored by between, say, 4 and 8 points (I haven't run a full analysis -- in fact, I'm trying to decide whether it would be worth the effort -- but that's my first impression).