This thesis investigates the relationship between the cognitive style of visualization, composed of an Object and a Spatial component, and its effects on numeracy and numerical decision-making contexts. Extant research points to spatial visualization skills aiding numerical performance. However, the findings are not conclusive and only refer to spatial visualization as a skill, not as a cognitive style. The role of object visualization on numerical skills and numerical decision-making contexts has been ignored altogether by previous research. This work aims to fill these gaps in the literature.
Firstly, the relationship between Object and Spatial visualization as parts of a cognitive style was investigated, with all performed studies consistently supporting the idea that these are two independent mental constructs. The study of the relationship between numeracy and visualization revealed that, while higher Object visualization predicts lower scores in a numeracy test (Abbreviated Numeracy Scale, ANS), higher Spatial visualization predicts greater numerical ability in the same test. This result proved to be consistent across all the experiments in this study.
Having established the relationship between the ANS and visualization, this study extended the investigation to other numerical and graphical scenarios which resemble tasks that could be found in natural scenarios. The results showed that spatial visualization predicts better performance in numerical and graphical tasks beyond the ANS.
This thesis then extended the investigation to see whether the biases Peter et al. (2006) and Weller et al. (2012), which were found to be affected by Numeracy, were also similarly affected by visualization, therefore widening the potential impact of visualization on the field of Decision-Making. The results indicated that in a task with a normatively correct answer, spatial visualization predicted better performance, whereas numeracy or object visualization did not have this effect. In the tasks where only judgments of preference or attractiveness were elicited, neither numeracy nor visualization predicted preferences or attractiveness.
Finally, this study investigated whether the cognitive style of visualization had an effect on individuals’ weighing information consistent with their cognitive style more heavily. In a task where participants saw information in the form of tables or graphs, accompanied by a human figure, it was found that neither spatial or object visualization preference seemed to influence the weighing of object or spatial information.
Overall, this thesis demonstrates the relationship between numeracy and visualization style, and is the first investigation demonstrating how visualization cognitive style is related to numeracy and how a person’s visualization cognitive style affects Decision-Making tasks. The close relationship found between Spatial visualization and Numeracy, with Spatial visualization in some cases predicting results where Numeracy failed to show a differential effect, also opens the door to further consideration of the use and creation of Spatial visualization measures to be used instead of Numeracy scales in the numerical decision-making contexts.
