Keeping in mind that I am looking at advanced users of English, all of whom have passed the English language proficiency requirements to enter the Univeristy of Calgary, here is a chart to go with a post I made a while ago when I was trying to think of all the different possible errors that can be associated with vocabulary in academic writing. I think I have basically narrowed it down to six categories: meaning, appropriacy, derivation, form, omission, and style. Out of those six categories, I think five of them have the greatest impact on the quality of student writing: meaning, appropriacy, derivation, form, and style. I'm thinking of leaving out omission from my final list when I begin to comb through the writing samples in my thesis project. I can then read through each of my writing samples, tagging the samples for five categories of vocabulary error. My plan to then to see if any patterns arise from the samples as a whole, and between the different groups in my corpus (native vs. non-native English speakers, different groups of NNES based on length of residence). I finally think I'm ready to start. Already, I'm fairly sure of what I'm going to find. So far, my NNES papers show are demonstrating a lack of depth of knowledge of vocabulary. The students seem to have a breadth of knowledge that stretches to about 11,000 word families of active vocabulary usage (compared to 17,000 for the native English speakers), but the problems lie in the categories of appropriacy, derivation, and form - in particular choosing the correct part of speech.
I'll keep you posted as to what I find. Enjoy my chart of possible vocabulary errors in academic writing.
P.S. It's May 4th. I just added spelling errors to my chart - I've decided orthography is an important part of vocabulary knowledge as well.