最少节点挂靠原则---英语语言学

最少节点挂靠原则(principle of minimal attachment)
最少节点挂靠原则是第二个己经被证实的策略,这个策略( Frazier, 1987; Frazier & Fodor, 1978)的主要内容是:当听者在构建句子新成份时,宁愿使用少的句法节点,(We prefer attaching new items into the phrase marker being constructed using the fewest syntactic nodes consistent with the rules of Language)即“选择简单的句子结构,而不是根据语法规则运用复杂的结构”(陈开顺,2001)。

比如下面这个句子中的 and 即可以看作连词,又可以看作是新名词短语的启始词。

依据最少节点挂靠原则,我们宁愿选择前一种解释方法(Frazier, 1982)。

(27.) Ernie kissed Marcie and her sister.
Frazier 和 Rayner 其实在1982的研究中就已经发现了这个认知策略,以下的两个句子是他们用作实验的:
(28.) The city council argued the mayor’s position forcefully.
(29.) The city council argued the mayor’s position was correct.
在这两个句子中,都出现了 mayor’s position 这个句法成份,不同的是,29句中的语法节点多于28句,依据最少节点挂靠原则,理解者识别28句的速度要快, 因为29句中的 mayor’s position 需要反复识别和调整的程序, 而28句中的 mayor’s position 直接理解为宾语即可,相对于29句来说,识别的速度就快多了。

Frazier 和 Rayner做的是阅读实验,但是对听音理解是否有相同的解释呢?为此,笔者做了测试,结果发现:在 argued 后边没有停顿(29)的情况下,结果基本一致,但是有停顿的情况下,结果还是有差异的,学生识别29句的速度相对来说说与28句的速度相差无几,这是因为 argued 后边的停顿给了学生一个很强的提示性信号,因此对29句识别就快多了。

Minimal attachment
One heuristic that has been proposed to explain how people make parsing decisions program, is called "minimal attachement." For example, given the sentence, "I saw the man with the telescope," how could a parser determine where the PP "with the telescope" attaches if using the following grammar?
S <- NP VP
VP <- VERB NP PP
VP <- VERB NP
NP <- ART NOUN
NP <- PRON
NP <- NP PP
S
/ \
/ \
/ \
/ \
NP VP
| / | \
| / | \
| / | \
PRON VERB NP PP
| | /\ |\
| | / \ | \
| | / \ | \
ART NOUN PREP NP
I saw | | | /\
| | | / \
| | | / \
ART NOUN
the man with | |
| |
| |
the telescope
Here's another acceptable parse tree for the same sentence, but this time the prepositional phrase attaches lower in the tree to the noun phrase and modifies "the man":
S
/ \
/ \
/ \
/ \
NP VP
| / \
| / \
| / \
PRON VERB NP
| | / \
| | / \
| | / \
NP PP
I saw /\ / \
/ \ / \
/ \ / \
ART NOUN PREP NP
| | | /\
| | | / \
| | | / \
ART NOUN
| |
the telescope
The minimal attachment principle says that the preferred parse is the simplest parse, and simplicity here is measured in terms of the number of non-terminals in the parse tree, where fewer non-terminals is considered to be simpler. Thus, the first parse tree above, which contains 13 non-terminals, is preferred by the minimal attachment principle over the second parse tree which contains 14 non-terminals.
This principle won't always work, however. If you used minimal attachment in parsing "We painted all the walls with cracks," the heuristic would select the wrong parse. (Add the following rule to the grammar above:
NP <- QUANT ART NOUN
and note that "all" is a QUANT.) Oh, the reason we know that it's the wrong parse is that we know what the sentence is supposed to mean. So, as you can see, it's going to be very hard to keep up this sham about a clean separation between syntax and meaning.
S
/ \
/ \
/ \
/ \
/ \
NP VP
| / | \
| / | \
| / | \
PRON VERB NP PP
| | /|\ |\
| | / | \ | \
| | / | \ | \
QUANT ART NOUN PREP NP
We painted | | | | |
| | | | |
| | | | |
NOUN
all the walls with |
|
|
cracks
The parse tree above has only 13 non-terminals, while the alternate below has 14
non-terminals:
S
/ \
/ \
/ \
/ \
/ \
NP VP
| / \
| / \
| / \
PRON VERB NP
| | / \
| | / \
| | / \
NP PP
We painted /|\ |\
/ | \ | \
/ | \ | \
QUANT ART NOUN PREP NP
| | | | |
| | | | |
| | | | |
NOUN
all the walls with |
|
|
cracks
Despite the fact that the latter parse tree makes more sense (I mean, you didn't actually use cracks to paint the walls, did you?), the minimal attachment heuristic prefers the former parse tree. Consequently, it's safe to conclude that the minimal attachment heuristic isn't perfect.
迟关闭原则问题
迟关闭原则通常也称做“右结合原则”，( Bever, 1973;Frazier, 1987; Frazier and
Foder197Kimball, 1913; Watt, 1970),迟关闭原则是指我们总是把听到的新成份纳入最新识别出的句法框架中( Frazier, 1987; Frazier ，Fodor, 1978),该策略的主要目的就是减轻句法分析过程中的工作记忆,( Fraizer, 1987)例如听到下面这句话:
(24.)Tom Said that Bill had taken the cleaning out yesterday.
上面句子中的 yesterday 有两种挂靠的方式,第一种方式是 yesterday纳入主句 Tom said 中,第二种方式是 yesterday 纳入到从句 Bill had taken…的框架中, Fraizer 和 Fodor (1978)认为理解者通常情况下会选择第二种方式,为了证明此理论的正确性,也是由于好奇心理的作用,笔者在听力课上向学生口述这个句子后,然后要求学生翻译听到的句子,结果大部分学生把这句话译成“汤姆说比尔昨天把房间打扫干净了。

”在下面的这句话中,我们又很容易把介词短语 in the library 看作是修饰动词 reading 而不是动词put 的句法成份:
(25.) Jessie put the book Kathy was reading in the Library. 1982年由 Frazier 和 Rayner 做的一个阅读实验再次支持并验证了这个原则,下面的句子就是他们在实验中所用到的:
(26.) Since Jay always jogs a mile seems like a very short distance to him.
很明显,这是一个歧义句,由于 jogs 后边少了一个逗号,从而引起歧义,实验发现，读者对后边几个词注视的次数多于对前几个注视的次数,这说明由于迟关闭原则的影响,读者起初错误地把 a mile 理解为 j ogs 的宾语,读到最后才发现不对,不得不做一些调整。

实事上,26是一个花园路径句子,对于这样句子的理解,我们同样可以用即时性原则来解释。

不难发现,以上所例举的这些句子都
有人为故意的因素,在正常的语言情景中,几乎不可能碰到这样的句子,那是不是说以上这些研究都毫无意义了呢? 当然不是的,正是这些实验解释了学习者的语言理解策略,并且这些策略具有自动性和瞬时性的特征,了解这样的认知策略,这会对我们的教学及其脑对语言的认知过都是很有启发的(对教学的启发在后边要讲到)。