Abstract

This article describes the levels of reading and the arguments provided by future secondary mathematics teachers from two Chilean universities when decoding the information presented in a histogram and a box plot. A qualitative methodology was followed, based on content analysis. As a data collection technique, an instrument with two activities was applied. The 36 participants were selected through non-probabilistic sampling. Among the main results, it was found that participants perform basic readings of graphical representations. The arguments provided are conceptual in nature and are not related to the activity’s context. Additionally, future teachers do not refute the conclusion formulated based on the box plot, which indicates that they do not connect the representation to the context; those who do fail to provide sufficient justification. The study concludes that there is a need to strengthen argumentation skills to foster statistical literacy and statistical thinking. © 2025 by the authors; licensee Modestum.