Complexity: Activity 3

Lexical complexity

In addition to the syntactic complexity you explored in Activity 2, you can also look at lexical richness as a measure of complexity. One way to measure lexical complexity is to calculate a type-token ratio (TTR): “the total number of different words used (types) divided by the total number of words (tokens) in the segment” (Ellis & Barkhuizen, 2005, p. 85). The closer the TTR is to one, the greater the lexical richness. In the following activity, we ask you to compare lexical complexity in Jiulin’s and AnnaLi’s oral and written narratives.

  1. Compute the TTR for the first 50-word segment of Jiulin’s oral and written narratives (See below). Here, we count each Chinese character as one word, omitting false starts, fillers and repetitions. Is there any difference in terms of the TTR between the oral and written tasks? What does this comparison tell you about Jiulin’s vocabulary use in the two tasks?
  2. From Jiulin’s oral narrative:

    嗯,比方说,嗯,好吃的饭,(laugh) 所以她有 一个钱包,嗯,还有, 嗯(…)还有一个 (…) 一个饭盒,饭盒的东西,嗯,她 (laugh) 她装她

    From Jiulin’s written narrative:


    *Nonexistent character

  3. Compute the TTR for the initial 50-word segment of AnnaLi’s oral and written narratives (see below). Compare them with Jiulin’s. How can you account for differences or similarities that you see between the learners and the tasks?

AnnaLi’s oral narrative:

有一天,嗯,两个女人(…)在买东西(…)嗯,一个是老女人, 一个是年轻的女人。年轻的女人有一个孩子在小车里。(…)嗯(…)嗯(…)年轻的女人(…)嗯, 停, 嗯,跟老人说话

AnnaLi’s written narrative:

有以天,两个女人在买 dōng西。一个女人带 (dài) 她的女儿一起买 dōng西。一个女人见到别的老女人, rán后他们就开 shǐ liáo天儿。她的女儿

Please type your answers to the questions in the box below.

When you have finished typing your answer, click to compare your response with the Learner Language staff response.

1. While counting characters, we excluded characters (crossed out and gray highlighted below) that were false starts, fillers and repetitions in Jiulin’s oral narrative (see below). No character is excluded in the written narrative.

,然后有一个(…)老人,她是女生。她去过, 她去一个(…)购物中心。 想买(…)饭,, 比方说,, 好吃的,(laugh) 所以一个钱包,还有(…)还有一个 (…) 一个饭盒, 饭盒的东西, (laugh)

The TTR for Jiulin’s oral narrative is 35/50 or .7.
The TTR for his written narrative is also 35/50 or .7.

Thus, the TTR suggests that the overall lexical complexity of his oral and written narratives was identical. However, we can also compare the variety within subclasses of words. Jiulin uses 7 different verbs (去,买,找,撞,聊,讲,提 ) in the written  narrative while he uses only 5 in the oral (是,去,买,有,装). Thus, there seems to be slightly more variety in his use of verbs in his written narrative than in his oral narrative.

2. Here again, we excluded characters that are false starts, fillers and repetitions in AnnaLi’s oral narrative (see below). No character is excluded in her written narrative.

有一天,,两个女人(…)在买东西(…)一个是老女人一个是年轻的 年轻的女人有一个孩子小车里。(…)(…)(…)年轻的女人(…), 停, ,跟老人说话

We compare Jiulin’s and AnnaLi’s overall TTRs in the two tasks (see below). First, Jiulin’s lexical complexity is greater than than AnnaLi’s in both tasks: .7 vs .5. Second, while we found earlier that Jiulin’s overall lexical complexity in the two tasks was very similar, here we see that AnnaLi tends to use slightly more variety in her overall word choice in the written narrative than in her oral narrative.


TTR for
Oral narrative

TTR for
Written narrative








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