Our second example extends the use of portraying partial adjustments on influence diagrams, and introduces the notion of path correlation. Consider the model (1), and suppose that we observe runs of the experiment in batches with three observations of both product yields in each batch. Thus batch 1 consists of the observations , and so forth. We will adjust the unknowns by each of the four batches sequentially. (Where experimentation is very expensive, it is obviously useful to identify the point at which further experimentation is expected to contribute little extra knowledge.)