Table 1.
Characterization of the poems that were used as stimulus materials.
Each poem was scored on aspects related to structural or conceptual fluency. See the text for a detailed description of how the scoring was done. Gramm. = Grammaticality.
Fig 1.
Displayed is the poem ‘Sterfbed’, an Easy poem in terms of fluency (Table 1), in the two fonts. On the left is the more readable font (Calibri) and on the right is the less readable font (Mistral).
Table 2.
The first four items were used as dependent variables in the analysis. Items 5 and 6 were control items, and items 7 and 8 assessed whether participants already knew the poems. Likert scales ranged from ‘Not at all’ (1) to ‘Very much’ (7).
Table 3.
Results of the statistical analysis.
ANCOVA’s were done for each of the four dependent variables General Liking, Perceived Flow, Perceived Topic Clarity, and Perceived Structure Clarity. The ANCOVA’s had three factors: Poem Difficulty (Low, High), Font Readability (Low, High) and Experiment (Exp. 1, Exp. 2, Exp. 3). The covariates Age and the answer to the question ‘Do you consider yourself to be a poetry lover?’ were added as covariates to explain additional variance. Note that for none of the dependent variables a statistically significant 3-way interaction was observed. We therefore did not analyze the data per experiment. We did observe a Poem Difficulty x Font Readability interaction for three of the four dependent variables, indicating that Font Readability has a differential effect on poems that have low or high difficulty.
Fig 2.
Bar graphs display mean scores (all scored on 1–7 Likert scales) for Easy or Difficult Poems (x-axis) depending on the Readability of the Font they were presented in (light and dark blue fill). For the dependent variables General Liking (A), Perceived Flow (B), and Perceived Structure Clarity (C) we observed statistically significant interactions between Font Readability and Poem Difficulty. This means that font readability affected the reading experience of Easy and Difficulty poems in different ways. Easy poems are scored lower on these three dependent variables when they are presented in a harder to read font compared to when presented in the easier to read font (left two bars). For the difficult poems there is numerical trend towards the opposite effect (scored higher when presented in hard to read font, right two bars), but this was not statistically reliable (see Results section). No Font Readability x Poem Difficulty interaction was observed for the fourth dependent variable, Perceived Topic Clarity (D). Note that the pattern for each dependent variable looks comparable, which is to be expected given the sizeable correlations between the scores. See text for statistical tests between conditions. Error bars represent 95% confidence intervals.
Fig 3.
Same data as in Fig 2, now displayed as violin plots to show the distribution of the data.
Note that the distribution of scores for Easy poems (left violins) are narrower than those for the Difficult poems (right violins). This shows that scoring was more similar across participants for the Easy as compared to the Difficult poems.
Fig 4.
Bar graphs display the mean scores (scorings on 1–7 Likert scale) for all conditions, for each Experiment separately. Note that different participants took part in each experiment and that different poems were used per experiment. Since the factor Experiment did not interact statistically with any other factor, we decided to collapse over Experiment in the results (see Fig 2). To give a complete picture of the data, we additionally plot the results per experiment here. Error bars represent 95% confidence intervals.
Table 4.
Correlations between dependent variables.
There were sizeable positive correlations between how participants scored the poems on the four main dependent variables (General Liking, Flow, Structure Clarity, Topic Clarity). All of these variables correlate negatively with perceived difficulty.