A Probability Plan of Action
Gougeon, Deborah J., Educational Research Quarterly
An often difficult topic for students who take a course in Introductory Business Statistics is the chapter on Probability, but, more specifically, the Addition Laws of Probability and the concepts of Independence versus Dependence. These concepts are covered in virtually every Business Statistics textbook [1, 2, and 3 as examples]; however, there is never a clear cut "plan of action" ("game plan" if you will) to help students grasp these difficult concepts in a straight-forward and outlined way, only the usual narrative that often adds to the complexity of these issues.
An effective teaching strategy for the successful teaching of these concepts can be seen in the Table which displays an outlined schematic of how these problems can be solved. This "plan of action" is also shown as a Concept Map which is powerful as a cognitive and assessment tool. It is also an effective way of representing visually how a student understands a domain of knowledge. The Concept Map visually organizes their thinking and summarizes the topics of study. This Table/Concept Map has been very helpful to probability students when they are confronted with the following questions:
1. Find the Probability of A or B (A U B)
2. Find the Probability of A and B (A n B)
3. Find the Probability of A given B (A / B)
The Table/Concept Map provides an effective, successful "plan of action" to answer these questions in a very logical structured manner. Key words such as or, and, and given direct the student through the Table/Concept Map on how to solve a particular probability problem. For example, when one is asked to find P (A or B) the word or directs one to the Addition Laws of Probability (see Roman Numeral I on the Table) and then the decision needs to be made as to whether the events are mutually exclusive or not to determine the correct rule to be used. When one is asked to find the P (A and B), the Joint Probability, or P (AJB), the Conditional Probability, then one proceeds to Roman Numeral II in the table to do a test of independence initially, where the opposite rule of what you're trying to determine is tested. …