Bx Examples Repository

Title: The Vanishing Allergy

Version: 0.1

Type: Sketch

For example, Precise, Industrial, Sketch. Use common sense concerning whether to use one or more: for example, Precise and Sketch should be mutually exclusive, but conceivably either might be combined with Industrial.


(This is a placeholder for an example from Dagstuhl.) This example relates to provenance. Suppose we have two healthcare systems, one used by a general practitioner and one by a specialist. The general practitioner's system records patients' allergies and ongoing drug prescriptions. The specialist's records some more detailed information, and the drug prescriptions made by this specialist - but not allergies. The consistency that is maintained is that drugs in the specialist system should also be in the GP's, and that no patient should be prescribed a drug to which they are allergic. Patient X is recorded by the GP as being allergic to Drug Y. Patient X sees a specialist, who would normally have prescribed Drug Y, but because of the allergy, uses skill to prescribe (more expensive or less effective) Drug Z instead. Later, the GP determines that Patient X is not, in fact, allergic to Drug Y. Ideally, the provenance of the decision to prescribe Drug Z would enable the GP to change the prescription to Drug Y - but usually, it wouldn't.

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A difficult issue that we have found arises in writing examples is how to handle the choice points. Typically in making an example, even a small one, precise, one realises that there are several points where more than one choice is reasonable. These multiply to give a potentially unmanageable set of examples. Our proposal is that one “base” example should be given in the main body of the text, and variation points described here.


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Perdita Stevens typing about an example by Jens Weber

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