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I need to do some parameterized expectation work. I read Chapter 7. It is not well-written. The authors first introduce the general framework, and then introduce a series of examples. People would be stuck at the general framework part. They don't know WHY do we do that. A better way to introduce this method would be to use one or two completely worked out examples, paying particular attention to explain the ideas behind doing what we are doing. This way people will know the ideas behind the method, even though not necessarily the general framework (who need to know the general framework anyway?) Then introduce the general framework, and more examples