For bettors, determining whether international tournament trends are meaningful is tricky and involves intuition.
The sample size is small. And if you wait for more data to snuff out variance, the tournament will be over.
Even so, it's worth considering early trends if you can explain them.
After all 24 teams in Euro 2020 completed their first match, here are three patterns I've seen, the implications they have for bettors and thoughts on whether they'll hold.
Second-Half Scoring
Our tournament field has scored 21 of its 28 goals after halftime, including nine in minutes 46-60 and another eight after the 75th minute.
Obviously, this is crucial information for live-betting totals.
I've won two bets playing live overs on a total of 2.5 goals, one just after Italy took a 1-0 lead on Turkey in the 53rd minute (+165), another at halftime of Slovakia's 2-1 win over Poland (+130). But I also suffered a frustrating defeat playing the total over 1.5 goals at halftime of Spain and Sweden's scoreless draw (+102).
Whether this disparity is likely to continue depends on why you believe it's happening.
If you think tactical adjustments following the opening 45 minutes of a tournament are often the most drastic, you might be right.
With international rosters and players' form so fluid, these games are much like a season-opener in club football. A coach can only truly learn the magnitude of his squad's strengths and weaknesses through real competition. Friendlies don't provide the same level of information.
At the same time, UEFA’s pandemic-related allowance of five subs might lead to more tactical flexibility late in matches. And that could keep the late goals coming.
Home-Field Disadvantage?
If you’ve backed sides playing before their home fans, you’re not doing very well.
To be more exact, if you put $100 on the moneyline on the nine teams playing in their home country, you’re currently down about $450, according to OddsPortal. If you bet $100 on each of their opponents, you've made almost $1,200 in profit. That's more than double your money.
Teams favored against a host country are perfect, although there’s only been two: Belgium and Portugal, both of whom won 3-0.
Hosting matches might be more curse than blessing for weaker sides who aren’t used to the attention. It’s easier for, say, Scotland and Hungary to stray from pragmatic strategies when the crowd urges you forward.
History also suggests this. None of the five "minnows" who have hosted or co-hosted this event since 2000 — Belgium, Switzerland, Austria, Poland and Ukraine — have reached the knockout phase.
There could also be some first-match jitters here. And the biggest upset against a host side came in extremely unusual circumstances.
Finland, roughly 10/1 underdogs, defeated Denmark in a match that was suspended and then restarted hours later following a terrifying cardiac incident involving Danish star Christian Eriksen.
Favorites Cruise, Darkhorses Struggle
For the group favorites, chalk has mostly prevailed. It's been a far tougher road for the second favorites.
Five of the six group favorites won their opening round matches. If you bet them $100 each, you’ve made $340 in profit, according to OddsPortal. That’s a 56.7% return on investment.
Of the six second-favorites, only Austria has secured victory. To be fair, Sweden will be plenty satisfied with its draw in Spain, and Croatia and Germany also opened against the favorites in their group.
I expect a much-improved effort from Denmark in their last two matches, and that Germany will progress despite a narrow opening loss to France.
But the early struggles of Switzerland and Denmark reflect the difficulty of transitioning from punching up to punching down.
