为什么本届世界杯的进球数少?

现在的足球比赛和上世纪五十年代的球赛有了很大的不同，再也不可能做到当时的平均每场比赛四个进球。然而，在本届世界杯进行的前16场比赛里，进球只有25个，平均每场1.56个，这结果比以前几届都差。

问题来了——这么少的进球究竟是为什么？有些人认为是世界杯用球“普天同庆”的原因，有些人归咎于功利足球的踢法。来看看下面这些原因吧。

After every World Cup team had played once, scoring remained at historical lows in the tournament. The 32 teams combined for just 25 goals in the first 16 games of the Cup, a rate of 1.56 goals per game. That's well down from 2.44 goals in the first 16 games at the 2006 World Cup, and 2.88 goals in 2002.

Overall in the Cup's first 16 games, teams took 410 shots, but just 106 of them were on target, according to ESPN's stats. That's a rate of 26%. In the first 16 games in 2006, there were 435 shots--barely more than this year. But 44% of them were on target. That percentage held for the entirety of the 2006 tournament.

Errant shooting appears to be the decisive factor in the low-scoring start to the Cup. Of the shots on goal in teams' first games this year, 23% found the back of the net--slightly higher than the rate of 20% in the first 16 games last year, and the 18% mark for the tournament overall. This year's rate also is in line with the 23% of shots on goal that were scores in 2002.

What might explain all the misfires? Here are some possible explanations:

． The ball.

Some players have complained about it, and it does seem like an inordinate number of shots are sailing over the woodwork (perhaps because of the altitude, not the ball). But players must adjust to the ball at each World Cup, and an uNPRedictable flight can affect goalies as well as shooters.

． Lack of scoring talent.

Perhaps players are shooting poorly because they are poor shooters. If that were the case, though, we might also expect scoring to be down in other top competitions. Yet during the 29 games in the knockout stage of this year's Champions League - the premier European club tournament, featuring most of the world's best players--teams scored 82 goals, compared to 59 in the equivalent 29 games in 2006.

． Stat-keeping quirks.

Whether a shot is on target is a judgment call, one different scorers make differently. For instance, while ESPN recorded 25 shots for Spain, five of them on goal, in its game against Switzerland on Wednesday, those numbers were 24 and eight, respectively, according to FIFA, the tournament organizers. Similarly, while ESPN had nine shots for the Swiss, two of them on target, FIFA had eight and three, respectively. That adds up to big differences: FIFA has an overall shooting percentage - the term I'll use for percentage of shots that are on goal, whether or not they go in - for the first 16 games of 33%, compared to 26% of shots on target by ESPN's count. (It's possible this is because FIFA doesn't count blocked shots as shots.) Similarly FIFA had an overall shooting percentage of 48% in 2006, compared to 44% for ESPN. However, they corresponded closely in 2002. And both data sources agree that there was a big drop between last year and this year, and that the shooting percentage in the first 16 games in 2006 was 44%.

． A statistical fluke.

As the Montreal Canadians demonstrated during their run deep into the NHL playoffs, and the Capitals did with their early exit, some teams shoot at surprisingly high percentages, and such performances tend not to be sustainable. Perhaps players have been unlucky and will gain their shooting touch in the last three quarters of the tournament.

． Parity and tactics.

Every team has played effective defense at times. The tournament's weakest teams seem to have taken to heart the lesson of Greece, the stunning 2004 champions of Europe, who jammed the box with defenders and stymied high-powered offenses. Just two teams have yielded more than two goals in the first 17 games of the tournament, and both reached that ignominious mark only after losing a player to a red card. One sign that players indeed have been frustrated and pushed to take shots far from the goal: FIFA has recorded 241 shots from outside the penalty area through the first 17 games, compared to 186 shots inside the penalty area. Of the closer shots, 40% were on goal, compared to 27% on the farther shots (the rest were blocked or wide). Equivalent stats for prior tournaments aren't readily available, though, so it's impossible to say if this represents a trend toward shooting from farther away.