A new approach is under way for the research agenda of environmental valuation. Rather than treating stated preference (SP) and revealed preference (RP) as competing valuation techniques, analysts have started to view them as complementary, where the strengths of each approach can be used to provide more precise and possibly more accurate benefit estimates. In this study, the authors reexamine the models and motives for combining SP and RP data. They also reconsider the interpretation of "consistent" or "inconsistent" findings of RP and SP data.
Herriges, Joseph A.; Kling, Catherine L.; and Azevedo, Christopher D., "Linking Revealed and Stated Preferences to Test External Validity" (1999). CARD Working Papers. 229.