Purpose In this study, scales are developed for phantasy and its determinants, which is accepted as an important variable in investment preference with an emotional finance perspective. The scales developed in this framework are narrative, divided mind, group feel, informed herding, uninformed herding and phantasy. In addition, the power of these determinants to explain phantasy was investigated. Design/methodology/approach For this purpose, the data was obtained between May 01, 2019 and November 30, 2019 via an online survey with convenience sampling. First, a pilot study consisting of 200 subjects was performed. Then, additional data was collected. The total number of subjects was 648. The authors used IBM SPSS Statistics and AMOS for analysis. Exploratory factor analysis and discriminant analysis were performed. In addition, confirmatory factor analysis was performed after an additional data collection process with structural equation modeling. Findings As a result of analyses, the validity and reliability of these scales were ensured statistically. It was also found that divided mind directly affects phantasy, but group feel and narrative indirectly affect by informed herding. The "unknown and new investment" preference, which is accepted as a typical feature of the bubble periods, is modeled with the relevant variables. In this framework, it has been found that the variables that refer individuals to the relevant investment preferences are phantasy, group feel, uninformed herding and divided mind. Originality/value The study is unique because of its findings and developed scales. The findings are valuable in that the theoretically alleged relations were also obtained empirically.