Date of Award


Document Type


Degree Name

Master of Arts in Psychological Science



First Reader/Committee Chair

Hideya Koshino


Whole number bias (WNB) has been defined as the tendency to apply natural number knowledge to rational numbers. This misapplication can often lead to erroneous responses in mathematical tasks and understanding of rational number properties. Whole number bias can be explored using Dual Processing Theories. According to Dual Processing Theory we have two types of thinking: Type I and Type II. Type I is fast, heuristic based, intuitive, and doesn’t require working memory, while Type II is slow, logic based, analytical, and requires working memory. Some researchers argue that WNB is an intuitive phenomenon and occurs from a failure to activate Type II thinking. Two models explain the relationship between Type I and Type II processing. Default Interventionist (DI) model states the two types of thinking are exclusive and we first activate Type I processing, then if conflict is detected we activate Type II thinking. Hybrid model states we have two types of Type I processing: heuristic intuitions and logical intuitions. According to Hybrid model, Type II processing is only activated if a higher order of thinking is required. Individual factors such as numeracy and math anxiety could affect WNB. Attentional Control Theory states that anxiety consumes mental resources, resulting in reduction of executive functioning, including the ability to inhibit internal and external stimuli that interferes with task performance. The purpose of this study was to assess WNB from a Dual Processing perspective and examine how individual differences such as numeracy and math anxiety would affect WNB and math performance in a fraction magnitude comparison task. It was predicted that individual differences in numeracy and math anxiety would help describe WNB according to each model. The results support the notion when numeracy is low, a process similar to what is described by DI will take place whereas when numeracy is high, a process similar to what is described by Hybrid model will take place.