If you have no firm expectation of what will happen. Then you have a random expectation.
1. Therefore, you believe that a win for England, a win for USA and a draw is as likely as each other.
2. Or you genuinely don't have an expectation because you have no information about either team. So you don't know about world rankings, the quality of the players in the team, the past results of the team etc.
Since I know, you haven't been living in a bubble, the second possibility isn't true. So you must believe the first.
If you believe the first, no one else will agree with you on it.
Simple.
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Why did I look at betting? Because it monetizes people's aggregate expectations.
Also it solves the problem of where 2 people can expect both sides to win at the same time. This is irrational. 2 rational agents should come to the same conclusions given the same information (but it happens because we aren't robots). By using money, we can aggregate the strengths of these expectations to come up with an aggregate level.
England are 4/7(1.58) odds on to win on betfair, that is a ~63.3% belief that England will win.
For completeness, ~28.6% a draw and ~19.6% of a USA win.
Note that the odds add up to over 100% (I could if I wanted, bet on all 3 outcomes and be guaranteed money, given that someone is willing to match however much I wanted to bet, but my money would be tied up for 6 months for a small payoff). This is because the odds on betfair aren't very efficient at the moment because only £9 has actually been matched. Also, because with a bet now, you lose over 6 months interest, it has to compensate for that.
Compare that to the Man Utd vs West Ham game today. The implied chances add up to 100.9%. This market is very fluid with £280,000+ matched so far.
Again for completeness, Man Utd to win (~67.6%), Draw (~21.7%), West Ham to win (~11.6%).
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So what do my ramblings mean? When you say you don't understand how people could come to the conclusion that England should win, you just aren't thinking properly.