Reading graphs: contributions to an integrative concept of literacy
In contrast to past educational research that views graph-related activities in terms of mental ability, I offer a conceptualization of graphing as a semiotic activity. This move provides a more viable account not only of individual experiences, familiarity and socio-cultural factors during graph reading, but also of errors committed by students and 'experts' alike. I outline a model of semiotic activity that contains two elements not present in other semiotic theories: the process of parsing the perceptual field to construct relevant signs and the grounding of a sign through the dialectic of sign-to-referent and referent-to-sign movements. This model of semiotic activity also implies an integration of research on graphing (and other sign-related activities) into a more general concept of literacy.