Ch. 20 | Exercise 1

# Chapter 20 | Exercise 1

### Case study ‘Diachronic and register variation of should and ought to’

For these exercises you will need the data set `should_ought` in` Rling`, which displays the frequencies of the modal auxiliaries with infinitives in four periods represented by COCA (1990–1994, 1995–1999, 2000–2004 and 2005–2009). The exercises combine motion charts with some methods that have been discussed in this book.

1.

Investigate how the distribution of infinitives with should and ought to has changed over a short period from 1990 to 2009. To do so, create a motion chart of should vs. ought to using the data in `should_ought` in `Rling`. Since the number of words in the corpus components is nearly equal, one can compare the actual frequencies without normalizing them. Create a motion chart of the verbs that were used with the modal auxiliaries and interpret the the general direction of language change.

2.

Compare the distribution of should and ought to across five registers of COCA. The frequencies are shown in Table 20.1.

Table 20.1. Frequencies of modal verbs should and ought to in five registers of COCA (1990 – 2009)
Spoken Fiction Magazine Newspaper Academic
should 88452 56658 68235 59858 81660
ought to 10720 3913 2191 2113 2297

In which registers are the frequencies lower or higher than expected? Use a mosaic plot with shading. Are the differences statistically significant?

3.

In principle, you can represent any entities as moving objects, not only collexemes. Using the data in Table 20.2, visualize how the frequencies of should and ought to were changing from 1990 to 2009 in five registers, using the registers as moving objects. What are your conclusions?

Table 20.2. Frequencies of modal verbs should and ought to in five registers and four periods represented in COCA (1990 – 2009)
Register Year should ought to
Spoken 1990 22233 3995
Spoken 1995 21448 2870
Spoken 2000 18547 1825
Spoken 2005 16986 1428
Fiction 1990 12345 1074
Fiction 1995 11856 819
Fiction 2000 12053 818
Fiction 2005 13374 789
Magazine 1990 16378 705
Magazine 1995 16025 581
Magazine 2000 15053 442
Magazine 2005 14078 347
Newspaper 1990 13430 599
Newspaper 1995 14637 525
Newspaper 2000 13110 462
Newspaper 2005 12495 361
Academic 1990 18798 636
Academic 1995 18916 589
Academic 2000 17691 518
Academic 2005 17361 389

```> library(Rling);library(googleVis) > data(should_ought) > mch <- gvisMotionChart(should_ought, idvar = "Verb", timevar = "Year") > plot(mch) ```

The chart will show an obvious decline of ought to as a modal auxiliary over 20 years.

First, create a table with the frequencies of the modal verbs in R:

```> should <- c(88452, 56658, 68235, 59858, 81660) > ought <- c(10720, 3913, 2191, 2113, 2297) > mod.reg <- rbind(should, ought) > colnames(mod.reg) <- c("Spoken", "Fiction", "Magazine", "Newspaper", "Academic") > mod.reg Spoken Fiction Magazine Newspaper Academic should 88452 56658 68235 59858 81660 ought 10720 3913 2191 2113 2297 > chisq.test(mod.reg) Pearson's Chi-squared test data: mod.reg X-squared = 7804.823, df = 4, p-value < 2.2e-16 > chisq.test(mod.reg)\$residuals Spoken Fiction Magazine Newspaper Academic should -16.74049 -2.063185 6.925206 5.730985 8.680305 ought 68.43570 8.434369 -28.310474 -23.428457 -35.485378 ```

The residuals show that the modal ought to is very strongly overrepresented in the spoken data, and strongly underrepresented in the press and academic texts. For should, the reverse holds, although the residuals are overall smaller, which indicates a more even distribution. All this can also be seen in a mosaic plot:

```> library(vcd) > mosaic(mod.reg, shade = TRUE, varnames = FALSE) ```

The data from Table 20.2 can be entered manually or copied, saved as a text file with tabs as delimiters and read as a table in R (see Chapter 2).

```> mod.reg.time <- read.table("YourDirectory/mod_reg_period.txt", header = TRUE) > mch1 <- gvisMotionChart(mod.reg.time, idvar = "Register", timevar = "Year") > plot(mch1) ```

The motion chart displays changes in the frequencies of both should and ought to in all registers. In the spoken subcorpus, the decline of ought to is especially dramatic. However, with the exception of fiction, the frequency of should is declining, too.