Özet:
Statistical reasoning is to understand and reason with statistical information and make interpretations based on sets of data (Gar eld, 2002). In this study, statistical reasoning types of preservice mathematics teachers studying in _Istanbul were investigated. Participants were 91 secondary and 82 elementary school preservice mathematics teachers studying in the last semester of their program. Instrument was Statistical Reasoning Assessment { SRA (Gar eld, 2003). It was translated to Turkish and then validity and reliability was examined before applying to preservice mathematics teachers. Data was analyzed descriptively. Results showed that both secondary and elementary school preservice mathematics teachers were successful in interpreting probability, understanding independence, interpreting two-way tables and understanding importance of large samples. On the other hand, there was lack of understanding in selecting appropriate average, correctly computing probability, sampling variability, distinguishing between correlation and causation. Also results showed that they had law of small numbers misconception and equiprobability bias. Furthermore a comparison between secondary and elementary school preservice mathematics teachers' statistical reasoning was done. Results showed that there was no statistical di erence between their reasoning types. In this regard, the results suggest that in order to address and develop their understanding in concepts and misconceptions, statistics courses are suggested to be given importance in mathematics education programs. Results, portraying the statistical reasonig types of preservice mathematics teachers in Istanbul, might also be taken as a basis for further resarch investigating preservice mathematics teachers' statiatistical reasoning types in Turkey.
