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CHAPTER FIVE DISCUSSIONS

This chapter discusses the results of this study. After an overview of the study,

effects of different intervention patterns on vocabulary learning and reading

comprehension will be discussed, and then possible explanations for the learners’

questionnaire responses will be provided.

Study Overview

This study expanded previous gloss research by exploring the combined effects

of gloss plus inferencing or retrieval on EFL learners’ vocabulary learning and reading

comprehension. The investigation was based on the assumption that gloss plus

inferencing or retrieval could induce higher involvement load but reduce the chance

of memorizing incorrect word meaning. To test the assumption, three intervention

conditions for words repeated three times were set up: inference plus two glosses,

retrieval between two glosses, and full glossing. In the quantitative aspect, data of

the learners’ vocabulary learning and reading comprehension performance as well as

their preference and usefulness responses were collected and compared among

treatment conditions via MANOVAs, ANOVA, independent-samples t tests,

Chi-square tests and descriptive statistics. In the qualitative aspect, the participants’

think-aloud data were analyzed based on their reading strategies and sense-making

process.

Effects of Interventions on Vocabulary Learning

Results of the participants’ vocabulary learning performance showed that all of

the intervention conditions led to word learning. Since all the treatments shared

features of repeated word exposures and glossed reading, the findings reconfirm the

value of exposure frequency and glossing for vocabulary learning (e.g. Hulstijn et al.,

1996). Among all the three treatments, the condition that benefited vocabulary

learning the most was the gloss-retrieval-gloss condition, followed by the

inference-gloss-gloss condition and the least in the full glossing condition. The

difference between full glossing and gloss-retrieval-gloss reached a significant level.

Detailed discussions on each treatment condition are presented in the following

sections.

The Full Glossing Condition

The word gain from the full glossing condition supports that glosses increase

noticing (Bowles, 2004; Hulstijn, 2001; Miyasako, 2002; Rott, 2005; Yanguas, 2009),

stimulate correct responses (Holley & King, 1971) and trigger rehearsal (Holley &

King, 1971; Watanabe, 1997). It also agreed with Rott’s (2007) contention that

reappearing glosses could frequently draw learners’ attention to the target words and

offer them repeated opportunities of isolating the glossed word from the surrounding

context to rehearse word meaning in working memory. However, among the three

treatments, full glossing only generated the least word gain. Although Rott found

that words glossed more times yielded better word gain, this study discovered that it

was not always the case. The full glossing condition, containing the highest glossing

frequency in this study, did not outperform the other two conditions with lower

frequency and was even significantly inferior to the gloss-retrieval-gloss condition on

the immediate and delayed meaning recall tests and the immediate meaning

recognition test. When the target words are glossed all the time, the participants may

use glosses more as a means of understanding the text than learning vocabulary

(Bowles, 2004). In addition, from the GGG learners’ self-report of the gloss use, it

was found that as the times of gloss appearance increased, the number of the learners

checking the gloss directly decreased and more learners ignored the words together

with the glosses or thought about the meaning themselves without checking the gloss.

In other words, the continuous reappearance of glosses may not automatically lead to

learners’ repeated processing of glosses in the margin, let alone increase the quantity

of attentional resources spent on a word as mentioned in Rott (2007). Therefore,

although the involvement load hypothesis predicted that a gloss occurrence resulted in

an involvement load of one because it induced learners’ need for word meaning, the

load of reappearing glosses is not necessarily multiplied by the times glosses occur as

Rott assumed.

The Gloss-retrieval-gloss Condition

From the results, the gloss-retrieval-gloss condition was found to be the best

glossing arrangement for a word occurring three times in the input passage. It not

only produced the greatest word gain in form and meaning but also suffered the least

meaning attrition, which supports the contentions that retrieval can strengthen the link

between form and meaning (Nation, 2001), foster retention (Rott, 2007) and attenuate

the forgetting rate (Wheeler, Ewers, & Buonanno, 2003). As Rott (2007) suggested,

the involvement load of a retrieval was assumed to be three because it stimulated need

of understanding a word, search for its meaning in the mental lexicon and evaluation

of whether the searched meaning was correct in context.

In the GRG condition, the initial glossing supports the idea that the connection

between form and meaning had better be established initially (Nation, 2001), or

learners’ meaning mapping tends to remain shallow and vague (Rott & Williams,

2003). The subsequent retrieval might be the key that makes the

gloss-retrieval-gloss condition superior to the full glossing condition because what

contributes to incidental vocabulary learning is not repetition alone but the repeated

opportunity of retrieval (Karpicke & Roediger, 2008; Nation, 2001). Although Rott

(2007) argued that the subsequent retrieval of a word after the initial glossing did not

further strengthen the form-meaning connection because learners might just focus on

comprehension of a continued text rather than attend to any word aspect, it is possible

that learners in the present study were able to pay more attention to the bolded but

unglossed word during retrieval because they were required to retrieve word meaning

without referring back to the previous glossed word encounter. If there is no

retrieval between glossed encounters, learners will not try recalling or inferring

meaning from context, which demands deeper mental processing (Hulstijn, 1992;

Hermann, 2003; Knight, 1994; Mondria & Boer, 1991) or a higher involvement load

(Laufer & Hulstijn, 2001) and thus yields better retention. The third word

appearance with glossing could serve as a confirmation of the retrieval. Without the

final conformational glossing, problems such as forgetting or uncertainty during the

retrieval could only be left unsolved. If Rott had glossed the third word occurrence

in the glossed-retrieval-bolded-bolded treatment, the treatment involving retrieval

probably would have significantly outperformed the four-gloss treatment.

The Inference-gloss-gloss Condition

Inference-gloss-gloss was the second best intervention condition found in this

study. The condition was not significantly better than the full glossing condition, but

it generated greater word learning than the full glossing condition by more than 10%

in immediate form and meaning recall and more than 8% in meaning recognition.

The better immediate word gain in the IGG condition may be linked to the search and

evaluation processes during inferencing that created higher involvement load (Laufer

& Hulstijn, 2001). Although the retention rate in the IGG condition was higher than

that in the full glossing condition as well, the forgetting rates of the former were not

lower than the latter probably because the greater amount of immediate word learning

might be subject to attrition more easily.

The effect of inference-gloss-gloss was also comparable to that of the best

condition, gloss-retrieval-gloss. In fact, the think-aloud analyses showed that

retrieval and inferencing exhibited in the current study had one feature in common.

Either during retrieval or during inferencing, the learners might rely on the context to

evaluate possible meanings for a word. The major difference between the two

conditions was that the former was primed with a glossed word encounter and more

likely to lead to a specific correct response while the latter required a learner to draw

on wider knowledge sources to derive meanings that tended to be vague and

error-prone even after repetitive hypothesis testing. That was why the rate of correct

retrieval was higher than that of correct inference. If the context for the first word

encounters had not been designed to provide enough clues, the rate of correct

inference could have been lower. The low rate of correct inference might limit word

learning in the IGG condition because it was found that correct inference significantly

yielded better form and meaning recall than incorrect inference in this condition.

When wrong inferences are made, as Hulstijn (1992) mentioned, the problem is

that learners need to unlearn incorrect inferences. In fact, not all incorrect inferences

can be easily corrected. Chances are that they can be incompletely corrected,

confused with correct glosses, fossilized in memory, etc. Analyses of think-aloud

data also showed that the IGG learners tended to express uncertainty about their

inferences by using more hedges before their guesses such as kě néng shì18 (maybe)

and providing several possible meanings for a target word. Such uncertainty might

prevent them from linking form and meaning in the memory. Therefore, although

inferencing can induce need, search and evaluation and its involvement load may not

be lower than retrieving, its error-prone and uncertain nature may reduce its effect on

initial form-meaning establishment.

In addition, inferencing has the following disadvantages. First, learners may

pay more attention to the association of context and meaning than the connection

between form and meaning (Mondria, 2003). Second, when the inferences are

correct, learners may think that they already know the words and thus spend less time

committing the words to memory or even will not bother remembering word meaning

as they have fulfilled the need of comprehension (Hulstijn et al., 1996; Mondria, 2003;

Sokman, 1997). Third, learners’ form-meaning mapping may not be stable because

they tend to only have a vague understanding of the target words during inferencing

and are more likely to skip the confirmation or disconfirmation of their guesses (Rott

& Williams, 2003). When an inferred meaning seems plausible in readers’ discourse

model, they may be satisfied with the meaning assignment and transfer the inferred

meaning to the next word encounter (Rott, 2005). Therefore, although inferencing

takes up high involvement load, it does not always result in better retention.

To improve the inferencing method, a follow-up verification can be added.

Fraser (1999) found that consulting a dictionary following inferencing increased word

meaning recall from either inferencing or dictionary consultation alone by 20% and

explained that verification following inferencing not only offset the problem of

making wrong inferences but also led to a greater depth of processing. A similar

reinforcing effect of verification was also observed in direct vocabulary teaching after

reading in Sonbul and Schmitt (2010) and the meaning-inferred method designed in

Mondria (2003). Although Mondria worried that verification such as word list

checking was quite time-consuming, the current design that simply provided

participants with glosses after inferencing could shorten the time needed for

dictionary consultation, instruction or tedious word list checking.

In short, although glossing facilitates vocabulary learning, repeating it every time

does not increase learning as much as leaving one word encounter unglossed for

inferencing or retrieval. Making the first word encounter unglossed for inferencing

and glossing the subsequent encounters may enhance learning but its effect is not as

obvious and stable as inserting a retrieval practice between glossed encounters.

Inference making tends to be error-prone, create a vague link between form and

meaning initially and make learners believe that they have acquired the words, while

retrieving is more likely to strengthen memory that has been established in the

previous glossed encounter. To maximize word learning, a sequence of initial

form-meaning connection, subsequent retrieval and final confirmation can be

followed.

Effects of Interventions on Reading Comprehension

Aside from vocabulary learning, the current study aimed to investigate whether

the treatment conditions fostered or hindered text comprehension. Following the

line of previous findings that glossing enhanced the comprehension of the text (e.g.

Yanguas, 2009), the present investigation further compared the effects of repeated

glossing and the combination of glossing with inferencing or retrieval on text

comprehension. The result showed that the difference in the treatments did not

constitute a significant factor in the learners’ comprehension performance. The

nonsignificant result could be attributed to the test method. This study designed a

choice test to measure the participants’ reading comprehension. Ko (2005) indicated

that there were pros and cons in every test format. Recall protocols are not suitable

for students who cannot express their thoughts accurately but are able to understand

the text perfectly. Results of cloze tests may be confounded with the influence of

contextual clues, the blank number and other decisions on the test format. Choice

tests may fail to detect readers’ comprehension accurately and consistently. Since

there is no perfect test method, the measurement choice should be taken into

consideration in the interpretation of results.

Although no significant treatment effect was found on reading comprehension,

there was a tendency that full glossing facilitated reading comprehension better. The

tendency supported Gettys et al.’s (2001) view that glosses could aid second language

reading by lessening learners’ burden of word-by-word decoding and Rott’s (2007)

argument that repeated glossing facilitated comprehension of the target words and the

entire proposition. In addition, the presence of glosses increased the likelihood of

correctly comprehending the propositions. The reason why the error-prone treatment

conditions involving inferencing or retrieval in one word encounter did not interfere

with comprehension significantly is probably that the readers were assisted with

glosses in the other two word encounters. To maximize learners’ attentional quality

on word learning but minimize misunderstanding in comprehension, provision of

glosses after obtrusive interventions such as inferencing or retrieval is advisable.

Strategy analyses also supported the use of glossing in facilitating

comprehension. During the unglossed word encounter, the learners in the IGG and

GRG conditions seemed to be so occupied with solving local word problems that they

exhibited little global reading. The observation is consistent with Ko (2005) that

glossing fosters the use of high-level strategy use. Although the use of glossing only

induces low involvement with the target vocabulary items (Laufer & Hulstijn, 2001),

it may free up learners’ mental resources for high involvement with the text.

The finding that there was no significant correlation between word gain and

reading comprehension seems to suggest that vocabulary learning and text

comprehension may operate on dissimilar mechanisms. As Rott (2007) reviewed,

word learning involves noticing the gap, isolating word from context, and

elaboratively associating form and meaning to make form-meaning connections in the

mental lexicon, but in comprehension, what matters is whether readers can rapidly

integrate the information existing in the text and possessed by themselves. Although

Rott also speculated that the retrieval task might take up attentional resources of text

comprehension, her speculation was not consistent with the nonsignificant correlation

found in the GRG condition. The inconsistent findings between Rott’s study and

this study might lie in the difference in the adopted test methods. Rott employed an

L1 recall task but this study used a choice test to measure comprehension. The recall

task has been criticized for involving a test of memory retrieval as well (Chang, 2006).

That could partially explain why Rott found that the learners recalled the least main

ideas under the retrieval task that was favorable to word learning. In her case, there

might have been competition for readers’ mental resources between text memory and

word memory rather than between comprehension and word storage.

Although no apparent causal relationship was observed between reading

comprehension and word learning in the current investigation, the word gain in the

IGG condition positively correlated with comprehension to a noticeable degree. The

positive correlation that almost reached a significant level echoes Rott’s (2000)

observation that the learners’ strategic approaches to word inferencing and reading

seemed related. In other words, the IGG condition could have the potential to bring

twofold benefits to word learning and reading comprehension. Nevertheless, the

IGG condition produced the least reading comprehension score. One possible

explanation for the findings is that although the word inferencing strategy may foster

reading comprehension, the error-prone inferences may offset the effect of inferencing

on comprehension. If more assistance such as meaning options or other instances of

a target word in context selected from the concordance data can be provided for the

IGG learners during their inferencing, the IGG condition may be an ideal condition

that can benefit vocabulary learning and reading comprehension greatly at the same

time.

As for the trade-off issue between vocabulary learning and reading

comprehension, no definite conclusion could be made from this study. Although

correlation analyses showed no significant correlation between vocabulary learning

and reading comprehension in each treatment, the concern for the trade-off issue

cannot be ruled out completely due to the following reasons. To begin with, the

comprehension score was found to negatively correlate with form recall and meaning

recognition to a mild degree in the GRG condition. Another possible trade-off could

exist in the full glossing condition as well. Although correlation analyses showed

the relationship between word gain and reading comprehension in the condition

almost reached a neutral state, the learners in this condition exhibited a contrast in

their average vocabulary and reading performance because they obtained the least

word gain but their comprehension score was the highest among all the groups.

Since no further solid evidence can be found in the present investigation, whether a

trade-off exists between vocabulary learning and reading comprehension is still

inconclusive.

In summary, in contrast to vocabulary learning, the treatment effect on reading

comprehension is not significant. Interpretations of the nonsignificant effect cannot

exclude the consideration of the test format. Although no definite conclusion can be

made from the statistical analyses, some tendencies can be observed from the results.

First of all, comprehension seems to be better facilitated in the full glossing condition

because glossing is more likely to lead to correct interpretation and enable readers to

have more mental resources saved from less word-solving for high-level

comprehension. Second, the nonsignificant correlations between word gain and

reading comprehension may imply that vocabulary learning operates on different

mechanisms from comprehension and that no obvious trade-off effect exists between

them. However, some evidence still suggests that there is a relationship between

vocabulary learning and reading comprehension. A positive correlation between

learning and comprehension that almost reached a significant level was noticed in the

IGG condition, so inferencing may play a role in both learning and comprehension.

Nevertheless, the condition also resulted in the poorest comprehension, so the effect

of inferencing may be offset by wrong inferences. In addition, a possible existence

of a trade-off between learning and comprehension cannot be completely eliminated

because the word gain in the GRG condition correlated with comprehension

somewhat negatively and the GGG condition, which yielded the least word learning,

turned out to result in the best comprehension.

Preference and Perceived Usefulness

The present study found that the learners had a positive attitude toward glossed

reading, which is consistent with previous findings (Bell & LeBlanc, 2000; Cheng &

Good, 2009; Jacobs, 1994; Jacobs et al., 1994; Ko, 2005). Unexpectedly, among the

three conditions involving glossing, full glossing was less preferred than glossing

three conditions involving glossing, full glossing was less preferred than glossing

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