Seminář: Investigating Measures of Association by Graphs and Tables of Critical Frequencies

There is lot of effort to find suitable measures of interestingness of association rules. The most known measures are confidence and support but there are tens of additional measures. Each association measure can be understood as a function of four independent variables. These variables correspond to frequencies from a fourfold contingency table of antecedent and succedent. A natural way to investigate functions is to study their graphs. However it is hard to deal with graphs of functions of four independent variables; thus graphs are generally not too much suitable to study association measures. We show that tables of critical frequencies can be used to overcome this difficulty for some important classes of association measures. We give an overview of important classes of association measures and then we show how the graphs of tables of critical frequencies describe behaviour of corresponding association measures in clear and concise way.