Frequently asked questions

All right, I admit it. Frequently is a bit of a stretch, more like two or three times. And even at that on some of the questions I may be exaggerating. Following are some of the questions I have been asked either through email or by posters on proline forums. Or just questions that I feel should be asked. I'll be adding to these as time permits.

If you find yourself unfamiliar with some of the terms used in the faq or on the site I also suggest reading the article on Basic Probability Theory.

If anyone has any more questions please email and I'll respond as well as adding the question to this list.
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What do the stars mean?

The stars on the prediction pages are used to indicate games with profitable proline betting opportunities. The gold stars are games in which one of the bets options has an advantage favouring the player. The more stars after a game the better! The number of stars is based on the players edge or win expectancy. If you are not familiar with these terms, I'll be discussing them in more detail later on. The silver stars indicate games where the lottery's advantage is very close to even.

Do you predict points won by?

The short answer to that is no! Many new to the site expect us to be able to predict the probable winner or whether or not a team will cover a certain point spread. This is not our intention. This may surprise you but we do not even consider who is going to win an important question. Bettors used to the concept of playing edges will understand what I mean when I say this. What we do here is provide a much more valuable and realistic service. We try to predict the probability of all the possible proline outcomes. This is not the same thing, as the best bets often lie with the more unlikely results. Once the probability of the outcomes are known the bet option is then mathematically analyzed to provide the correct betting strategy. It is important to understand that the most likely result is not neccessarily the best bet! The best bet is the option with the highest Player Edge or win expectancy. If you are unfamiliar with these terms they will be covered in greater depth later.

What do all the game stats mean?

The prediction pages are the main feature of the site. On these pages we list all the games and determine the probability of each possible proline option for each game. To explain the various stats I'll use this example from an actual NFL game.

Seattle-GreenBay example

The items in the bold heading are fairly obvious. We give the lottery's game number as well as the starting time, league and team matchup. This is followed by the current offshore betting line for the game including the current over-under on the game if relevant. The logo, in this case Pinnacle, shows which offshore book's line is used. Although other information is also used, the prediction is primarily based on this number. The offshore line and all the data derived from it is automatically updated every 15 minutes.

The Win Probability row gives the predicted probaiblity of each proline betting option.

The Game Odds row is simply the payout odds offered by the lottery corporation for that wager. The Correct Odds row shows what the payout should be, based on the probability of the outcome occurring, in order for this to be a fair or break-even wager. What we want are cases were the actual proline odds are higher than the correct or fair odds. In gambling speak this is often referred to as an overlay. It is these cases where profitable opportunities lie and the exact value of them is determined in the following row.

The Player Edge row is the final key to it all! The values here are also often referred to as the win expectancy or value of the wager. If you had the opportunity to wager on this outcome you should, averaged over time, expect to win or lose this percentage of your wager. The profitable situations are of course those greater than zero and these are highlighted in yellow to make them easy to spot. In the above example the Home bet (Green Bay) has a Player Edge of +17.5%. It would be reasonable to expect this wager to return a profit of $17.50 for every $100 wagered. This assumed win rate is of course your expectation averaged over time.

Vancouver-StLouis example

I have added one more actual example just to illustrate that it is not neccessary for the best bet to be the most probable winner. Note that in the above the Canucks are a heavy favourite to win this game at a Win Probability of 67.0%. However the correct bet is the Blues with a Player Edge of +5.5%. Although you will only win this wager a third of the time, the high payout on the Blues of 3.20 will in the long term lead to an overall average profit.

Although not included in the above example the procedure for Point Spread and Total bets is the same.

Does all this work since I have to bet parlays?

Although the analysis here is all done on a game by game basis, parlaying the games which have a player edge will produce parlays which also have an edge. In the near future some tools will be made available here which will allow you to calculate the Win Probability and Player Edge for parlays.

What does Parlay-Under and Parlay-Over mean?

The Parlay Under and Parlay Over stats give the probability of a combination of one wager from the proline sides and one wager from the over under option in the same game. In some sports, especially baseball, it may be possible to find an edge by combining a specific game result with either the over or the under.

Arizona-SanDiego example

In the above example the Parlay Under 7.5 shows the payouts and probabilites for the combination bet Under and any of the proline options. The Parlay Over 7.5 shows the payouts and probabilites combination of Over and a side option.

We'll look at the combination of Under and Tie. Notice that although both the under and the tie have a negative expectancy, the combination bet of Parlay Under + Tie is an edge play. The combination payout of 4.50 is just a straight multiplication of the Under payout (1.80) and the Tie payout (2.50). Normally the combination's win probability could also be calculated in the same way. That would not in this case be accurate because the two events are not independent of each other. On average the tie has a probability of 34.8%, but this figure is much higher in low scoring games, and lower in high scoring games. The actual probability of the combined result is determined by finding similiar situations in a large data base of past results.

How are predictions made?

This is certainly the most important of the questions! It is also the most difficult because the answer varies from sport to sport and for each of the various bet options available. But I will try to briefly shed some light on the procedures used.

Before proceeding I want to emphasize that I do not believe the methods used here are the only valid means of handicapping proline. Not even necessarily the best. They represent my personal efforts to find the best value possible on proline plays. I'm sure that quite often you will disagree with the values given. You should! In the end the money bet is yours and you must be the one to make the final decisions. I only hope that I can steer you away from some of the worst choices towards the better options.

The short answer to the above question is the use of Vegas or Offshore Lines. With the exception of BBH bets, which are discussed in the next section, the Offshore line is used as an indicator of the probable result for all the bet options. These lines may be the best tool we have for finding value on the proline lists. Offshore bookmakers and Vegas casinos will accept huge amounts of money bet into these lines with vigorish that is usually set at around 4% and often even lower. I believe that either directly, through the oddsmakers who set the lines, and indirectly through the people whose bets change the lines during the day, we in effect can utilise the opinions of what probably represent the best sports handicappers in the world! Even in cases where you feel that your own handicapping has provided a stronger play, knowing the offshore line is important. I would for example never accept a proline baseball payout of 1.60 if the offshore line rated this game as a pick. This degree of error by a major offshore book is just not a very likely possiblity!

Now down to some more specific cases.

The easiest to explain are the baseball V-H and the scccer V-T-H. For these options the Offshore books use a money line which exactly corresponds to the way these bets are offered on proline (Ontario at least, others may vary). In these cases math can be used to directly convert the line into proline prediction probabilities. In any case where the Offshore line can be directly converted to a proline win probability this approach is used. The line displayed for each game, after the name of the book from which it is taken, is the main offshore betting line for that event. In most games additional lines are available and are used by the program to evaluate the proline options. For example, in baseball most of the betting is done on the money line but the run line and even the alt-run line when available are also being used.

Now the trickier things. Many events do lend themselves to such a straight forward approach. The method used here is to review the database of past scores for games in which the offshore line is similar. In some cases not only the line for the sides is used but also the game total.

Other sports and other bet options, such as V+, H+, over-under, and so on, use an approach much the same as the one above. In all cases where a point-spread (as opposed to money line) or total is used, the probabitlites are are also adjusted for any money line associated with that spread. This is actually more important than is immediately apparent. For example, a proline baseball total of 8.5 when the offshore total is 9.5 may seem like a good bet (and it usually is!) but if the 9.5 is actually 9.5 under -130 then most of the value of that 1 run difference has been lost. If we clarify the proline total to 8.5 over 1.60 at the same time we now have a negative value bet. Reverse these numbers to 9.5 over -130 and proline 8.5 over 1.80 and you will probably have an outstanding value play. The effect of the money differences can be very significant. For situations like this I find the expected values calculated here to be extremely accurate.

Sorry that this explanation was in some respects too long, while in other respects far too short. I hope that to some degree it clarifies where the predictions come from.

What about the BBH predictions?

The BBH predictions are formulated by comparing what I consider relevant factors in the game to the database of past hitter scores. My statistical analysis of past results have indicated that predictions based on the TB per game average of the hitters correlated to the line on the game itself shows a fairly realiable pattern for future predictions.

The major problem with this is that the database of past results is not as large as I would wish. Be extremely dubious in unusal situations. For example : games where the visiting team is a 3-1 favourite, one hitter has a TB per game of 1 and his opponent a TB per game of 3, you get the idea. The sample being drawn upon there is way too small to be significant. As time goes by and the database of past scores grows this method will become stronger.

There are some other obvious pitfalls and shortcomings in this approach. Most will be apparent to long time baseball bettors immediately so I won't expand on that here. But in total, I believe that the predictions are accurate enough that, with some thought to each game, any value plays indicated will over time produce a positive result and I would bet them personally.

A few of the offshore books do offer wagers on Total Bases and when a proline matchup is also available at an offshore book the proline predictions will be based on that line.

Where do you get the lines?

I have accounts at numerous offshore books and as required the line quoted could come from any of them. In practice, the line will generally be from Pinnacle Sports. This is a highly respected operation and their linemakers are generally regarded as amongst the sharpest in the business. If you're one of their customers this is not really what you want to hear. But for our purposes it is! Also, Pinnacle provides a constantly updated linefeed for use by other sites. This service eases the chore of updating the lines regularly on this website over the course of the day.

How often will the lines be updated?

During the day, between 4:00AM and 9:00PM (ET) the lines should be automatically updated every 15 minutes.

What about Golf and Nascar?

As with other sports the predictions are based on offshore lines whenever a corresponding matchup can be fournd at a top rated book. In the cases where this not not possible, then for Nascar the odds to win for each driver are converted to predictions for the matchups.

Is there a user forum?


For many years I resisted offering a user forum. There are already some out there and I felt this was enough for the proline community. But unfortunately with the closing of the BigTip forum this left a vacancy for edge players. There was really nowhere for edge players to discuss plays and strategy.

The link to our forum - ProlinePlayer Forum. The posters there include many of the BigTip crew and are very knowledgeable. Here you can ask questions of some of the most respected members of the proline playing community.