1(e.g. elderly people, children & second language learners,people with disability, etc.)3John sold the textbook to Mary
Structurally simpler
5Mary burst into tears and ran out of the room
 Mary cried and ran out of the room
more frequente.g.) Structural paraphrasing
morefamiliar
 It is John that sold the textbook to Mary

Simplify texts
Comprehension aid / reading assistancee.g.) Lexical paraphrasing

For readers (internet users)

Paraphrasing (2/2)

Examining the optimal format andcontent of a text is an essential taskFocus: readability assessment of a text

to enhance information exchange andfacilitate internet use
 to make information available for varioususers

If our goals in this ubiquitous society are

Readability assessment

COE postdoc
Computational Linguistics Laboratory

Michiko Nakamura

Measuring the effects ofparaphrasing on readability(proposal)

Interpersonal communication(e-mails, chat, letters, etc.)

Q: How late is Daiei open?
Q: What time does Daiei close?

For machines (e.g., Q&A, MT)

4

The secretary of the president
who was abducted…..

The president’s secretary
who was abducted…

ùfívÇ≥ÇÍÇΩëÂÅ

2

6Are paraphrased sentences actually easier toread than original sentences?
 Can we test the effect of paraphrasing
empirically?
Questions to be asked

Paraphrased sentences are simpler, andthus easier for the reader

Assumption

Paraphrasing as comprehension aid

9:50pmParaphrasing is used:

Provides alternative expressions for a given
phrase/sentence

Paraphrasing (1/2)

Information sources(books, newspapers, Internet, etc.)Primary means of transmitting information

Written texts

easierdifficulteasier ??

The details will be presented in the talk.

Present study (proposal)------------------------.
------------------------.
Sentence A------------------------.

------------------------.
------------------------.
Sentence A A’
Paraphrase------------------------.

(less complex)(structurally complex)

How about…

Paraphrase A’

Sentence A

119710 Users, purpose of reading, genre of texts, etc.

Implementation in NLP

12Do we need different readability criteria for differentusers? (e.g., Inui & Yamamoto 2001)
 ‘Readability’ may be specific to:IssuesWide range of paraphrasing types(structural, semantic, lexical, etc.)
 Their interaction effects
 Wide range of users

Beginning of a series of studies
Needs investigation

Limitations & future workSmåland is called “The Kingdom of Glass”.
It is located to the south-west of Stockholm.
The reason is that there are 16 glass
manufacturers in this area.

Småland, which is located to the south-westof Stockholm, is called “The Kingdom ofGlass”. The reason is that there are 16 glass
manufacturers in this area.
↓(Inui & Nogami 2001)

Discourse-level effect (example)

8

Discourse-level effect of paraphrasing[See http://cl.naist.jp/lab/kura/ParaCorpus/ for more complete list ofbibliography]



Dealt with paraphrased sentences in isolation(Inui & Yamamoto 2001)

paraphrased sentences are actually easier
 the effect can be observed during reading

Still not clear as to whether:‘more general’ readability criteria?
 future application to the Internet(e.g., children, L2 learners, even adults, etc.)

Certain structures are difficult to otherusers as well

Remaining issues

Subjective readability judgment data

(Canning & Taito 1999; Carroll 1998)

 English-speaking aphasics(Inui & Yamamoto 2001; Inui 2001; Inui et al. 2003)

 Hearing impaired people

User-specific readability criteria

Discourse-level effect







Far more attention to paraphrase generation
Very few studies on evaluating the effect ofparaphrasing on readability

Previous studies

13

Assessing the readability of a text is an important
issue
Focus on ‘paraphrasing’ that has a potential realizing
an optimal content of a written text for various users
Propose an experimental study that is designed totest the effect of paraphrasing on the readability of atext
The results will give us important clues as to whatkinds of factors affect text readability & thus need tobe considered in creating an optimal content ofinternet documents

To summarize