Can someone explain betting odds?

[Poiuyt]

I was looking up what the bookmakers think of the 2020 election, but I don't know what the numbers mean. What does it mean if person A is -105 and person B is +600?

[aeromanKC]

1. Person A is going to beat Person B (in a landslide)

Unless the Russians are involved.

[Poiuyt]

3. God I hope not!

Person A is trump.

I'm assuming that trump has an advantage now because the Dems haven't nominated anyone yet and that things will shift when we get closer to knowing who the Democratic nominee will be. Still, it's worrisome because oddsmakers are playing with real money and are not swayed by emotion.

[LeftInTX]

4. Think of Brexit

Bookies bet that Brexit would lose.

I think of all the money the betters lost. They bookies seem to be wrong alot.

[Poiuyt]

5. Thanks

I just worry a lot!

[mr_lebowski]

8. See my note below ...

[LeftInTX]

9. In the US, we use poll based aggregates for odds.

Keep in mind, if the odds are in a candidate favor, it is not the same as a poll. The odds were in Hillary's favor, but the odds were slight. However, polls were turning away from Clinton just before elections day:

https://www.realclearpolitics.com/epolls/2016/president/mi/michigan_trump_vs_clinton-5533.html

https://www.realclearpolitics.com/epolls/2016/president/fl/florida_trump_vs_clinton-5635.html

https://www.realclearpolitics.com/epolls/2016/president/oh/ohio_trump_vs_clinton-5634.html

https://www.realclearpolitics.com/epolls/2016/president/wi/wisconsin_trump_vs_clinton-5659.html

https://www.realclearpolitics.com/epolls/2016/president/pa/pennsylvania_trump_vs_clinton-5633.html

Note that Michigan and Pennsylvania favored Trump on the very last poll. Ohio and Florida strongly favored Trump leading up to the election. Wisconsin did not conduct a poll after Nov 2nd.

[DonaldsRump]

12. In several of the last polls, the only one showing Trump winning was the Trafalgar Group

What the hell is the Trafalgar Group? I'm curious how this little known polling company could be so prescient for Michigan, Florida, and Pennsylvania in the last and only poll cited by "Real Clear" Politics showing Trump would eke out small victories in each of those states, in addition to being almost on the money on the final EV count.

This is what a quick search shows about the Trafalgar Group:

2016 elections

During the 2016 presidential election, Trafalgar Group correctly predicted that Donald Trump would win the election in Michigan and Pennsylvania and the Electoral College vote. Cahaly's method included asking respondents who they believed their neighbors were voting for. He said that these responses indicated to him that Trump would receive the votes of many who were reluctant to support Trump publicly. In November 2016, Cahaly told PoliZette, "I believe that demonstrates that there are still people indicating they are uncomfortable saying they will vote for [Trump], but will say that their neighbor will vote for him."[5]

The day of the election, Trafalgar Group projected Trump to win 306 electoral votes and Clinton to win 232.[6] Trump won 304 electoral votes to Clinton's 227.

https://ballotpedia.org/Trafalgar_Group

That's awfully good. Emphasis on the word "awfully".

Does anyone have more info on the Trafalgar Group and its incredible ability to predict races?

[mr_lebowski]

7. If bettors lost a lot of money, that would mean the bookies were right ...

They are 'opposing sides', you see?

Honestly the way bookies operate is they strive to set odds/spreads such that there's equal money on both sides. This is why as, say, a football game approaches, the 'spread' (number of points the winning team must win by in order for bettors on the winning team to be paid out) often will change ...

Imagine a Cowboys/Eagles game ... the spread might go off Monday at -3 for the Cowboys (meaning Cowboys must win by >3 if you bet on them for you to be paid, or Eagles must lose by <3 if you bet the Eagles ... exactly 3 is a 'push' and you just keep your bet like it didn't happen often times ... more about this later).

That initial spread is geared towards getting even amounts of money on either team. IF it doesn't work out that way, say 10000 is bet on Cowboys at -3 and 1000 is bet on the Eagles at +3 (+3 Eagles/-3 Cowboys is two ways of saying the same thing, generally the minus is used, and that tells you who the favorite to win is) ... then maybe on Wednesday, the bookies will switch to taking bets (made after that point) at Cowboys -5. This in theory gets more people to throw money on the Eagles.

Again, the goal is not to 'pick the right winner', the goal is get even money on either opponent.

You might think ... WHY?

The answer: The VIG, aka commission, percentage, cut, etc.

AKA, the % of everyone's bet they take automatically (except for a push, typically). Usually it's just a few %, but it adds up. Like, you bet 100 at 2:1 odds, you'll usually collect like 190 or so, and the bookie keeps 5% vig.

This involves NO RISK at time of the contest, if they did a good enough job of evening out the bets on the two opponents by setting the spread/odds as the contest approached.

So it's not really 'what the bookies think' in terms 'a winner', it's what the bookies think ... the betting public thinks.

[LeftInTX]

15. Got it!

[rampartc]

11. bookies are never wrong

in fact, odds are set such that there is always a vig, or edge, for the bookie.

(as an example) the saints were favored by 9 points over the titans. this does not mean that anyone in vegas cares whether the saints win by 8, ot 10, or at all. it means that they want equal amounts of money bet on both teams. all bets are $11 for $10, so the bookie pockets $1 for every $10 placed no matter who wins.

[mr_lebowski]

14. Lol ... I just posted the same right above ya :)

GMTA

[LeftInTX]

2. Hilary had a 60/40 odds of beating Trump on election day

If it was a weather forecast, it means a 40% chance of rain. We got the rain.

It is very different than a poll. Polls in various swing states were showing her at like 51%. However the polls couldn't be trusted because of Comey and his bomb announcement on October 28th.

In your case, you're looking at single bets. I don't trust bookmakers. They seem to be wrong all of the time. They are merely trading on a gambling market. It's no different than a football pool. They were way off on Brexit. I think of all the gamblers who lost money on bets.

The odds in the US were not best on gambling, but on poll aggregates. Since Hillary had numerous 51% polls, they gave her a slight odd 60%.

I had a degree in math. Too many people were assuming the odds were polls. They are not. The odds for Obama winning a second term was pretty high.

[BSdetect]

13. Bookies at racetracks "lay off" large risky bets to other bookies to spread their loss risk.

[Make7]

6. Moneyline odds:

https://www.thelines.com/betting/moneyline/

If you bet $105 on Person A at -105, you would receive a payout of $205. (Odds 20 to 21)
If you bet $100 on Person B at +600, you would receive a payout of $700. (Odds 6 to 1)

Negative numbers mean that Person is more likely to win (the number is how much you have to bet to win $100), positive numbers mean they are less likely to win (how much you win if you bet $100).

[LeftInTX]

10. The Dem nominee needs to win: PA, MI, and WI and hold all other wins from 2016 to win in 2020