Methods and statistical analyses

In this section, I explain the methods for the selection of a subcorpus for multimodal analysis and present an initial quantitative analysis. The purpose of the quantitative analysis of spatial deictics is to determine whether spatial deixis is more common in high-rated OPs and to confirm (like Simpson-Vlach; 2006) that spatial deictics are more frequent in hard disciplines. Verbal spatial deixis is prototypically performed with demonstratives (this, that, these, and those) either used as determiners (e.g. this image) or pronouns (e.g. If you look at this), and the most frequent adverbs of location here and there. Other adverbs of location (e.g. around, everywhere)

are not considered here given their low frequency in the corpus. It is expected that the use of these deictics is accompanied by the use of other semiotic modes.

4.6.1. Selection of a subcorpus and data clean-up

To perform the analyses, it was necessary to select a subcorpus due to the difficulties that multimodal analysis implies. The following is a description of the difficulties and the actions to overcome them.

This thesis uses a 72811-token oral subcorpus created from 88 OPs (see 3.3.4). The performance of statistical and multimodal analyses of spatial deictics (this, that, these, those, here and there) that I propose in this chapter presented a few difficulties. First, not all incidences of these expressions are necessarily cases of spatial deixis. Spatial deictic expressions refer to the immediate spatial context. In the case of oral presentations, spatial deictics refer to aspects such as graphs and visuals on slides, the screen and its parts, parts of the room where the presentation takes place, among others. Expressions like that can perform other functions: subordinator of noun and adjective clauses, anaphoras/cataphoras, or determiners. Similarly, there can be used as grammatical subject in the existential constructions there be or there exist. A second difficulty is that not all cases of spatial deictics and their corresponding gestural actions can be seen on the OP videos. In several cases, the camera is focused on other aspects such as the slides or the audience. Third, the analysis of spatial deictics and their corresponding actions on video is highly time-consuming.

To overcome these difficulties in the analyses, the following actions were taken.

First, a sub-corpus of 30 OPs videos and their corresponding transcriptions was selected: 14 hard-field and 16 soft-field OP videos. Similarly, 30 video-transcripts pairs include 10 pairs

from each level of oral performance (high, medium, and low). These distributions closely represent those distributions in the general corpus. On all videos, the actions performed by the presenters doing deixis can be seen. Concordance lines of this, that, these, those, here, and there were obtained using AntConc (Anthony, 2014) and classified in spreadsheets by level and discipline. Raw and normalised frequencies were calculated too. (Table 4.1 and Table 4.2)

Table 4.1. Use of spatial deictics by level of achievement: raw and normalized (N) frequencies

Tokens This N That N These N Those N Here N There N Total N High 8717 175 200.8 160 183.5 34 39.0 2 2.3 9 10.3 15 17.2 395 453.1 Medium 8423 155 184.0 112 133.0 35 41.6 3 3.6 13 15.4 17 20.2 335 397.7 Low 7035 128 181.9 52 73.9 38 54.0 2 2.8 0 0.0 21 29.9 241 342.6 24175 458 189.5 324 134.0 107 44.3 7 2.9 22 9.1 53 21.9 971 401.7

Table 4.2. Use of spatial deictics by discipline: raw and normalized (N) frequencies

Tokens This N That N These N Those N Here N There N Total N Hard 10752 245 227.9 135 125.6 78 72.5 2 1.9 19 17.7 23 21.4 502 466.9 Soft 13423 213 158.7 189 140.8 29 21.6 5 3.7 3 2.2 30 22.3 469 349.4 24175 458 189.5 324 134.0 107 44.3 7 2.9 22 9.1 53 21.9 971 401.7

Second, to guarantee that only occurrences of spatial deictics were included, the identified sentences were manually analysed in their context using the file viewer option in AntConc along with their corresponding video. The following cases were eliminated: (1) sentences containing occurrences of the target expressions that were not expressing spatial or symbolic deixis (e.g. subordinating that, anaphoric this); symbolic deixis cases including pointing were kept (2) sequential repetitions and false starts (e.g. this, this, this microscope was used…; this use of [fs] we use the microscope…); (3) cases where spatial deictic expressions alignment with a deictic action was not seen on video.

Third, the deictic actions that were considered were gazing, body alignment, pointing, and position in regard to the screen (Rendle-Short, 2006). Change of any of these aspects was also considered in the selection of sentences, for there were cases in which such gestures (e.g. pointing actions) were almost static, and it was not clear whether the coordination of the deictic gesture and the deictic expression was intentional.

Fourth, after the identification of cases of multimodal spatial deictics, new frequency and significance analyses were performed by level of achievement and discipline (Table 4.3 and Table 4.4).

Table 4.3. Spatial deictics expressed in raw and normalised (N) frequencies by level of achievement Tokens This N That N These N Those N Here N There N Total N High 8717 80 91.8 15 17.2 21 24.1 1 1.1 5 5.7 4 4.6 126 144.5 Medium 8423 67 79.5 1 1.2 24 28.5 0 0.0 12 14.2 7 8.3 111 131.8

Low 7035 59 83.9 1 1.4 13 18.5 0 0.0 0 0.0 2 2.8 75 106.6

24175 206 85.2 17 7.0 58 24.0 1 0.4 17 7.0 13 5.4 312 129.1

Table 4.4. Spatial deictics expressed in raw and normalised (N) frequencies by discipline

Tokens This N That N These N Those N Here N There N Total N Hard 10752 136 126.5 9 8.4 47 43.7 0 0.0 16 14.9 6 5.6 214 199.0

Soft 13423 70 52.1 8 6.0 11 8.2 1 0.7 1 0.7 7 5.2 98 73.0

24175 206 85.2 17 7.0 58 24.0 1 0.4 17 7.0 13 5.4 312 129.1

The general analyses of normalised frequencies show that there are bigger differences in the disciplinary divide than in the level of achievement. These bigger differences are evident in the use of this (more recurrent in the hard disciplines than in the soft ones). Deictic that

frequency of use difference, however, seems to be more relevant in the level of achievement divide. To know what frequency differences are statistically significant, log likelihood and BIC calculations were performed based on the raw (observed) frequencies.

4.6.2. Statistical significance analysis

The purpose of the significance analyses (3.4.2) is twofold: (1) identify what frequency differences are statistically significant as expressed by LL values and (2) determine the amount of evidence against null hypotheses. In this chapter, I decided to analyse and report cases whose Log Likelihood (Table 3.4) and BIC (Table 3.5) values were above 10.83 and 6 correspondingly.

The null hypotheses for the two comparisons are

- Level of achievement: there is no difference between high, medium, and low achievers in terms of spatial deictics use frequencies.

- Disciplines: there is no difference between hard and soft discipline students in terms of spatial deictics use frequencies.

Table 4.5. Significance analyses of spatial deictics use by levels of achievement

Observed frequencies Totals

Hig

h Medium Low log likelihood Bayes Factor BIC

This 80 67 59 206 0.77 -19.42 That 15 1 1 17 20.09 -0.10 These 21 24 13 58 1.64 -18.55 Those 1 0 0 1 2.04 -18.15 Here 5 12 0 17 14.91 -5.28 There 4 7 2 13 2.28 -17.91 Corpus sizes 8717 8423 7035 24175

Table 4.6. Significance analyses of spatial deictics use by discipline

Observed frequencies Totals

Hard Soft log likelihood Bayes Factor BIC

This 136 70 206 38.70 28.60 That 9 8 17 0.49 -9.60 These 47 11 58 32.76 22.67 Those 0 1 1 1.18 -8.92 Here 16 1 17 19.50 9.40 There 6 7 13 0.01 -10.08 Corpus sizes 10752 13423 24175

As can be seen in Table 4.5 Table 4.6, only deictics this, these and here for the

disciplinary divide passed my test, which is in alignment with Simpson-Vlach’s (2006) finding that this, these, those, here, there, and then were more common in the hard sciences. In my study, this means that we can be sure that the frequency differences among the disciplinary groups for the gestural and verbal use of this, these, and here are not random; additionally, the evidence against the null hypothesis is very strong.