5. Discussion
We combined the HJDM and supply management literatures by distinguishing among rational, experience-based, and emotional processing and examining their interactions and relationships with the financial and non-financial performance of the supplier. Our results show that rational processing by the individual decision maker is positively related to financial and non-financial performance. This finding corroborates rational processing theories, which assume that extensive information gathering creates a deep comprehension of context variables, such as market developments and the pursuit of long-term strategies (Glöckner and Witteman, 2010; Miller, 2008), and that clear definitions of criteria help in choosing a high-performing supplier (Kaufmann et al., 2012). Through high procedural rationality, decision-makers also might be able to mitigate biases and therefore the potential downsides of using intuitive approaches (Carter et al., 2007). Thus, our findings underscore the key role of rationality in the supplier selection decision (Kaufmann et al., 2014; Miller, 2008).