When annotating Type 1 sentences, annotators were required to indicate the first and last words in the compound clause. In example (23), the first occurrence of the word you would be annotated as the first word and irritable would be annotated as the last word in the compound clause.
(23) For example, you may not sleep well or you may become irritable because you have frequent hot flushes, and not directly because of a low oestrogen level.
Manual annotation of Type 1 sentences thus yields information about the auto- matically identified clause coordinator and the manually annotated span of the compound clause. From this markup, the annotation tool implements a variant of inside, outside (IO) encoding in which every token in the sequence receives a tag to indicate whether it occurs before the compound clause, within the compound
clause but before the sign, within the compound clause,3 within the compound
clause but after the sign, or after the compound clause. The annotators were also asked to indicate when the sign of syntactic complexity triggering the annotation had been incorrectly tagged and to indicate when they were unable to decide on the class to which the sequence belongs. As a result, the total number of classes used in this scheme is seven:
1. BEFORE_COMPOUND_CLAUSE, 2. IN_COMPOUND_CLAUSE_BEFORESIGN, 3. IN_COMPOUND_CLAUSE, 4. IN_COMPOUND_CLAUSE_AFTERSIGN, 5. AFTER_COMPOUND_CLAUSE, 6. NOT_CLAUSE_COORDINATOR, and 7. UNDECIDED.
This annotation produced a data file suitable for use by automatic sequence tagging methods such as CRF++ (Kudo,2005). Table4.2presents the annotation prompted by the occurrence of a clause coordinator in Sentence (23).
When describing the manual annotation of sentences containing subordinate clauses in the second dataset, it should be noted that English sentences may include various types of complex constituent (e.g. adjectival phrases, adverbial
Table 4.2: Annotated sentence containing a compound clause.
Position in Token
sequence Token PoS number Class label
1 For IN 582_1 BEFORE_COMPOUND 2 example NN 582_2 BEFORE_COMPOUND 3 , ESMP 582_3 BEFORE_COMPOUND 4 you PRP 582_4 IN_COMPOUND_BEFORESIGN 5 may MD 582_5 IN_COMPOUND_BEFORESIGN 6 not RB 582_6 IN_COMPOUND_BEFORESIGN 7 sleep VB 582_7 IN_COMPOUND_BEFORESIGN 8 well RB 582_8 IN_COMPOUND_BEFORESIGN
9 [or] CEV 582_9 IN_COMPOUND
10 you PRP 582_10 IN_COMPOUND_AFTERSIGN 11 may MD 582_11 IN_COMPOUND_AFTERSIGN 12 become VB 582_12 IN_COMPOUND_AFTERSIGN 13 irritable JJ 582_13 IN_COMPOUND_AFTERSIGN 14 because IN 582_14 AFTER_COMPOUND 15 you PRP 582_15 AFTER_COMPOUND 16 have VBP 582_16 AFTER_COMPOUND 17 frequent JJ 582_17 AFTER_COMPOUND 18 hot JJ 582_18 AFTER_COMPOUND 19 flushes NNS 582_19 AFTER_COMPOUND 20 ,_and CMP 582_20 AFTER_COMPOUND 21 not RB 582_21 AFTER_COMPOUND 22 directly RB 582_22 AFTER_COMPOUND 23 because IN 582_23 AFTER_COMPOUND 24 of IN 582_24 AFTER_COMPOUND 25 a DT 582_25 AFTER_COMPOUND 26 low JJ 582_26 AFTER_COMPOUND 27 oestrogen NN 582_27 AFTER_COMPOUND 28 level NN 582_28 AFTER_COMPOUND 29 . . 582_29 AFTER_COMPOUND
phrases, noun phrases, and verb phrases), often in the same sentence.4 Further-
more, even when considering complex NPs in isolation, these may be modified by
4In the examples provided here, the spans of complex constituents, including complex NPs
and compound clauses are marked using square brackets. In some examples, constituents may be multiply embedded. Subordinate clauses and the conjoins of compound clauses are underlined. In examples (24)–(28), only one complex noun phrase in each sentence is bracketed.
various types of finite and non-finite clause (e.g. (24)–(28)).
(24) The County Court in Nottingham heard that [Roger Gedge, 30], had his leg amputated following the incident outside a rock festival in Wollaton Park, Nottingham, five years ago.
(25) [Tomkins, who married at 20], told police that her husband was a domi- neering man who drank and was careless with money.
(26) They were asked by [David Price, solicitor advocate for Mr Burstein], to award damages of between £20,000 and £50,000.
(27) When [the mum of two, from Cheltenham, Glos], heard a rear window break, she feared for her life and accelerated at 40 mph, trapping Gedge.
(28) “The evidence is so thin, it is effectively invisible,” said [Gareth Peirce, representing Eidarous].
One of the aims of my sentence simplification method (Section 5.2.1) is to simplify Type 2 sentences containing complexRF NPs, such as (25)). While the
sign tagger that we developed (Section3.2) is accurate, it provides no additional information on the particular functions of the subordinate clauses detected in a sentence. For this reason, human annotators were required to encode information on the syntactic functions of each of the identified subordinate clauses. They were instructed to indicate the first and last words in the complex constituent that the
clause modifies and also to label its function. For this purpose, the annotation scheme includes ten different functions which are available for selection:
• Adjectival: The clause modifies an adjectival phrase (29).
(29) “I am [very pleased that we don’t].”
• Adverbial: The clause is adverbial or modifies an adverbial (30).
(30) They were walking home from a party [when he was attacked by Aaron Lee Martin, 25].
• Cleft: the clause is used in a cleft, pseudo-cleft,5 or inverted pseudo-cleft
construction6 (31).
(31) On the other hand, altering it would be costly - £220m according to the RCN but rising rapidly as more old people enter the homes over the next two decades - and [it is the better off who would benefit, by saving their homes to hand on to their children].
• Independent: The clause is independent (32).
(32) [Means-testing rules are tightly enforced: anyone who transfers
5E.g. [That people can love one another was the message he wanted to express]. 6E.g. [This is the first time in the city’s history that it has achieved a figure this high].
ownership of their house to try to escape paying will still be made to pay if they need to go into a home within seven years].
• Intensifying: The clause is used in an intensifying construction (33).
(33) Some are [so aroused by the feisty character, depicted wearing tight- fitting clothing, that they have put nude versions of her on the internet].
• Reporting: The clause is a reporting clause. (34)
(34) A consultant gynaecologist nibbled at a patient’s ear then told her it was all part of the treatment, a Manchester court was told yesterday.
• Restrictive: The clause is restrictive and modifies an otherwise generic or non-specific noun phrase (35).
(35) “It has been incredibly traumatic and is [something that I will never forget].”
• Verbal: The clause is the obligatory argument of a clause complement verb (36).
(36) Penelope Tomkins, 49, who [claimed that she could not end the affair but was unable to leave her husband for fear of losing the love of her two grown-up children], was jailed for 3 years after admitting soliciting to murder between June 28 and October 28 last year.
• Wh-clause: The clause modifies another type of wh-phrase, but not nom- inally bound which and not an adverbial (37).
(37) “Obviously, no one would have wished what happened to Mr Gedge but perhaps now in hindsight he will realise if he hadn’t done some- thing as obscene in the first place, it would never have happened.”
• Non-nominal: The clause is bound but not nominally bound. i.e. the superordinate phrase is not nominal and the clause does not belong to any of the classes previously listed (38).
(38) In Graves’ disease the thyroid gland [usually enlarges, which causes a swelling (goitre) in the neck].
The annotation of sentences containing complex constituents was made in a similar way to the annotation of sentences containing compound clauses. The annotators were required to identify the first and last word in each complex con- stituent or subordinate clause in the corpus to be annotated. To illustrate, they were required to identify the first and last word in each of the square bracketed
sequences in examples (29), (31), (33), (35)–(36), and (38). In examples (30), (32), (34), and (37), they were required to annotate the first and last word of each of the underlined sequences. In both cases, they were also required to indi- cate the function of the subordinate clause. The annotators were also asked to indicate cases in which the sign of syntactic complexity triggering the annotation had been incorrectly tagged and to indicate when they were unable to decide on the class to which the sequence belongs.
Manual annotation of these sentences thus yields information about the au- tomatically identified left boundary of the subordinate clause, the manually an- notated span of the complex constituent, and the manually annotated function of the clause. As in the case when annotating Type 1 sentences, the annotation tool implements a variant of IO encoding in which every token in the sequence receives a tag to indicate whether it occurs before the complex constituent, within the complex constituent but before the sign, within the complex constituent (and is the sign), within the complex constituent but after the sign, or after the com- plex constituent.
As a result, the total number of classes used in this scheme is 54, with examples including BEFORE_ADJECTIVAL, IN_COGNITIVE_COMMUNICATIVE_- VP_BEFORESIGN, IN_INTENSIFYING_CLAUSE, IN_RESTRICTIVE_CL- AUSE_AFTERSIGN, and AFTER_ADVERBIAL. To illustrate, Table 4.3 dis- plays the annotation of Sentence (39).
Figure 4.1: Interface used for manual annotation of complex constituents
next month for further questioning.
Both types of annotation were made using an annotation tool which displays the input sentence with the triggering sign of syntactic complexity highlighted in square brackets, the token numbers of words, and brief instructions and in- formation about the annotation scheme. The highlighting of the triggering sign facilitates accurate annotation of sentences containing multiple clause coordina- tors or multiple left boundaries of subordinate clauses. In the latter case, for example, annotators were instructed only to annotate the complex constituent modified by the specific subordinate clause introduced by the highlighted sign. Figure 4.1 displays the interface of this tool.7