MAPPING ACIDIFICATION RESEARCH - A TEST OF THE CO-WORD METHOD

This paper extends the co-word method for mapping science, adopting new statistical and graphical methods to explore time-series data and the changing distribution of effort between different research themes. It also tests the reliability of the co-word method, comparing co-word data on the acidification of the environment with data derived from a large scale interview study. Overall, the study increases our confidence in the reliability of the co-word method. In particular, it leads us to the following conclusions: (a) that the PASCAL database is representative, at least in the area of acidification research; (b) that indexer bias is negligible; and (c) that the co-word method satisfactorily identifies groups of research themes and the way in which these evolve.