ABSTRACT
Inference is reasoning that converts data and other information into evidence that can support or discredit a qualitative or quantitative hypothesis. For example, the body of evidence supports the hypothesis that low dissolved oxygen caused the fish kill and that the kill occurred where levels were below 2 mg/L. There are three types of inference: Deduction, Induction, and Abduction. In this chapter, I briefly describe the major categories of inferential methods commonly used in environmental assessment. In the end, most of your inferences by any of these methods will be some variant of abduction.
