Mirko Maracci has written an article that has recently been published (online first) by ZDM. The article is called “Combining different theoretical perspectives for analyzing students’ difficulties in vector spaces theory“, and it originates in a doctorate research project investigating the errors and difficulties in vector space theory of graduate and undergraduate students. The data was analyzed with two different theoretical frameworks:

• Efraim Fischbein’s (founder of PME) theory of tacit models
• Anna Sfard‘s process/object duality theory