I've worked on Appraisal in multinational corporations' Sustainability Reports for my Masters' thesis.
Identifying and quantifying Appraisal automatically, I've found, implies some challenging methodological issues. You could try to have a look at these references. They have been helpful to me.
- Hunston, S. (2004). Counting the uncountable: problems of identifying evaluation in a text and in a corpus. In Partington, M. and Haarman, L. (eds.), Corpora and Discourse. Peter Lang, 157-188.
- Kaltenbacher, M. 2006. ''Culture related linguistic differences in tourist websites: the emotive and the factual. A corpus analysis within the framework of Appraisal?. In: Thompson, G. & S. Hunston (eds). System and Corpus. Exploring Connections. London: Equinox: 269-292.
I've also come across a couple of studies of Appraisal in Sentiment Analysis (freely available on the Web). Even if my background is different they were stimulating and useful.
Hope this helps.
From Corpora List
