Post on 18-Jan-2017
Lexical density is “the kind of complexity
that is typical of written language” (Halliday, 1985, p.62)
Readability "depends on several factors including
the average length of sentences, the number of
new words contained, and the grammatical
complexity of the language used in a passage.”
(Richards, et al.,1992, p.306)
Identify the changes of lexical density and readability;
Discover the consistency between the measurements
of lexical density and readability.
Find out the relationship between lexical density,
readability and text levels;
1. How do lexical density and readability change across
levels in the selected texts in English textbooks?
2. What is the relationship between lexical density,
readability and text levels?
3. What is the correlation between the methods adopted to
access lexical density and readability?
How to measure LEXICAL DENSITY?
1. Ure’s method:
(Ure, 1971; Halliday, 1985)
Lexical density = the number of lexical items x 100
the total words
When you heat a liquid, it can change into gas.
Lexical density = the number of lexical items x 100
the total words
(Ure, 1971; Halliday, 1985)
When you heat a liquid, it can change into gas.
Lexical density: 40%
How to measure LEXICAL DENSITY?
1. Ure’s method:
Lexical density = the number of lexical items
the number of clauses
(Halliday, 1985)
How to measure LEXICAL DENSITY?
2. Halliday’s method:
When you heat a liquid, it can change into gas.
Lexical density: 2
Grammatical items:
Determiners, pronouns, most prepositions, conjunctions,
some classes of adverb and finite verbs. (Halliday, 1985)
Lexical items:
Nouns, verbs, adjectives and adverbs are the four word classes
belonging to lexical items (T.Le, Yue, & Le, 2011).
Some kinds of lexical items and grammatical
items were determined differently by linguists
and researchers in literature
(To, V. et al., 2013)
Halliday (1985) /Ure (1971): Phrasal verbs: give up, eat out
O’Loughlin (1995): All prepositions, conjunctions, quantifiers
Castello (2002, cited in Castello, 2008, p.56-57) :
3-word sequence prepositions: in view of, in terms of
open-class quantifiers: heaps of, a great deal of
complex conjunctions and subordinators: provided that,
regardless of
“it does not matter exactly where we draw
the line provided we do it consistently”. (Halliday, 1985, p.63)
Word Class Notes
All NOUNS • university, David, Apple A compound noun /
phrasal verb /compound
adjective - a lexical item
E.g. long-term, eat out,
good-looking
All LEXICAL VERBS
• Eat, read, think
All ADJECTIVES
old, beautiful, useful
Two kinds of ADVERBS
• Manner adverbs: quickly, beautifully • Sentence adverbs: honestly, fortunately
Word class Examples
All PRONOUNS
• Personal pronouns I, you, she, them, one
• Demonstrative pronouns this, that, these, those
• Possessive pronouns mine, yours, his, hers, its,
• Reflexive pronouns myself, yourself, himself
• Indefinite pronouns nothing, anyone, another
Word class
Examples
All DETERMINERS
• Articles a, an, the
• Possessive
adjectives
my, your, his, her
• Quantifiers some, any, many, few,
• Numerals one, sixteen, second, third
Word class Examples
All FINITE VERBS
• Be
am, is, are, was, were, been
• Do
do, does, did
• Have
have, has, had
• Modals can, may, probably, certainly
Be, Do, Have as main verbs Lexical items
Be, Do, Have as auxiliaries Grammatical items
• I am a student. • I have cereal for breakfast. • The student did his homework.
• I am talking. He was beaten. • You have done a good job. • Did the student do his
homework?
Word class Examples
Some classes of ADVERBS
• Temporal adverbs • Locative adverbs
now, then, today, always, later, beforehand, afterwards here, there, below, above, outside, upstairs, indoors
• Degree adverbs very, too, so, rather, quite
• Negative and Interrogative ADV
Not, never, when, where, how
Word class Examples
All CONJUNCTIONS and, but, however, therefore
All PREPOSITIONS in, at, of, with, between
All DISCOURSE MARKERS Oh, well, you know, I mean
All INTERJECTIONS Oh, my god, my godness, gosh
All REACTIVE TOKENS yes, no, O.K, right, mm
“It is not always easy, however, to recognise what a
clause is. Again, for comparative purposes, the main
requirement is consistency”
(Halliday, 1985, p.67)
Hypotactic clauses:
|||Now, I often eat this soup ||when I am tired or worried.|||
Paratactic clauses:
|||Now, I often eat this soup || and it helps me feel better.|||
|||These students often feel overwhelmed ||and will put off doing
many things they need to.|||
Non-defining relative clauses:
|||The only Asian country to adopt it at that time was the Philippines,
||which the Spanish invaded in the sixteenth century.|||
(Halliday & Mathiessen, 2004; Lukin, 2013)
Defining relative clauses:
|| People everywhere appreciate individuals [[who are interested in getting to know them and learn about their ways of doing things]]||
Interrupting clauses
||They had to be transported, [[in order to reach safety]], through floodwaters.||
Non-finite clauses
|| [[ To be successful, and to enjoy your experience abroad,]] you must be flexible, open-minded, and both eager and willing to learn new ways of doing things. ||
(Humphrey et al., 2012; Lukin, 2013)
Reading Ease = 206.835 – 0.846 wl – 1.015 sl
(Flesch, 1948)
Flesch Reading Ease Description of style
0-30 Very difficult 30-50 Difficult 50-60 Fairly difficult 60-70 Standard
70-80 Fairly easy
80-90 Easy
90-100 Very easy
How to measure READABILITY?
3. Flesh’s method:
(Flesch, 1948)
Flesch Reading Ease Description of style
0-10 Very easy
10-20 Easy
20-30 Fairly easy 30-40 Standard
40-50 Fairly difficult 50-70 Difficult
70-100 Very difficult
Reading Ease = 206.835 – 0.846 wl – 1.015 sl
How to measure READABILITY?
3. Flesh’s method:
Lexical items
Total words
Ranking clauses
Halliday and Ure’s formulas
Flesch Reading Ease Scale
Correlation
(To, V. et al., 2013a)
Texts 1 (Elementary)
2 (Pre-
intermediate)
3 (Intermediate)
4 (Upper-
intermediate)
Total words 173 160 162 165
Lexical words 84 73 61 75
Ranking clauses 24 14 15 11
Lexical density
Ure’s method
49% 46% 38% 46%
Halliday’s method
3.5 5.2
4.1
6.8
Flesch’s method
25 53 48 44
LEXICAL DENSITY and READABILITY among chosen reading texts in English textbooks
Figure 1: Ure's method
49% 46%
38%
46%
0%
10%
20%
30%
40%
50%
60%
Text 1 Text 2 Text 3 Text 4
The changes of LEXICAL DENSITY across levels
Figure 2: Halliday's method
3.5
5.2
4.1
6.8
0
1
2
3
4
5
6
7
8
Text 1 Text 2 Text 3 Text 4
The changes of LEXICAL DENSITY across levels
25
53 48
44
0
10
20
30
40
50
60
Text 1 Text 2 Text 3 Text 4
The changes of READABILITY across levels
Figure 3: Flesh's method
The relationship between LEXICAL DENSITY, READABILITY and TEXT LEVELS
Levels Lexical density Readability
Ure’s method Halliday’s method
Flesh’s method
Elementary the highest the lowest the easiest
Pre-intermediate high high the most difficult
Intermediate the lowest high fairly difficult
Upper-Intermediate
high the highest fairly difficult
Texts Lexical density Correlation coefficient
Ure’s
method
Halliday’s
method
Flesch’s
method
Halliday &
Ure’s method
Halliday &
Flesch’s
method
Flesh & Ure’s
method
1 49 3.5 25
0.1
0.5
-0.6
2 46 5.2 53
3 38 4.1 48
4 46 6.8 44
The correlation between the methods employed
Ure’s method revealed that lexical density did not
match the text levels and text difficulty.
In contrast, Halliday’s method of lexical density
corresponded to the text levels and readability.
As for Flesh Reading Ease, readability increased from
low to high. However, the highest level did not entail
the highest readability.
1. Ure’s method:
Lexical density did not match the text levels and text difficulty
(Text 1 was the most dense; Text 3 was the least dense).
The texts chosen for the lexical density analysis in the four
books may not necessarily represent the complexity for each of
the books.
In this study, the density is only a factor for judging
complexity.
the ILLOGICAL result
2. Halliday’s method:
Lexical density corresponded to the text levels and readability.
(Text 1 was the least dense; Text 4 was the most dense)
It may convince us that Halliday's approach in measuring lexical
density is MORE CONSISTENT, thus more powerful.
Halliday-based findings are LOGICAL
3. Flesh’s Reading Ease Scale:
Readability increased from low to high. However the highest level
did not entail the highest readability.
(Text 2 was the most difficult)
Lexical density alone cannot fully explain about readability.
HALLIDAY 'S METHOD is CONSISTENT and applies well
in measuring lexical density in relation to other
grammatical features such as nominalisation,
grammatical metaphor, etc.
CONSISTENCY is important in analysing lexical density .
LEXICAL DENSITY is only ONE ASPECT of text
complexity. Thus it alone cannot completely explain
about readability.
This is only 'EXPLORATORY‘ study.
• The findings support HALLIDAY’S THEORY.
• Regarding URE’S METHOD and FLESH READING EASE
It raises more questions than answering .
Anderson, N. J. (2003). Active Skills for Reading, Books 1 - 4. Boston: Heinle / Cengage.
Castello, E. (2008). Text complexity and reading comprehension tests. Bern: Peter Lang.
Flesch, R. F. (1948). A New Readability Yardstick. Journal of Applied Psychology, 32, 221-233.
Halliday, M. A. K. (1985). Spoken and written language. 1st ed. [Waurn Ponds], Vic: Deakin University.
Halliday, M. A. K., & Matthiessen, C. M. I. M. (2004). An introduction to functional grammar (3rd ed.). London: Arnold.
Humphrey, S., Droga, L. & Feez, S. (2012). Grammar and meaning. Newtown: PETAA.
Le.T., Yue, Y., & Le, Q. (2011). Linguistic complexity and its relation to language and literacy education. New York: Nova Science Publishers, Inc.
Lukin, A. (2013). Embedded Clause.: A guide for the confused but conscientious (Lecture). Macquarie University. Retrieved from http://vimeo.com/66871477
O'Loughlin, K. (1995). Lexical density in Candidate output on two versions of An oral Proficiency Test. Melbourne Papers in Language Teaching, 26-48.
Richards, J. C., Platt, J., & Platt, H. (1992). Longman dictionary of language teaching and applied linguistics. London: Longman.
To, V., Fan, S. & Thomas, DP. (2013a). Lexical density and Readability: A case study of English Textbooks. The International Journal of Language, Society and Culture, 37(7), 61-71.
To, V., Le, T.& Fan, S. (2013b). Different perspectives on linguistic complexity. In T.Le, Q.Le & Fan, S. (Eds), Innovative trends in Language and literacy education in a global discourse. Malaysia: Pearson Longman. (in press)
Ure, J. (1971). Lexical density and register differentiation. In G.E. Perren & J.L.M. Trimm (eds). Applications of Linguistics: selected papers of the 2nd International Congress of Applied Linguists, London: Cambridge University Press, 443-452.