As originally developed by Charles Ragin in The Comparative Method (1987), qualitative comparative analysis (QCA) has been used extensively by comparative and historical sociologistsas an effective tool for analyzing data sets of medium-N populations. Like many other methods, however, QCA is atemporal and obscures the sequential nature of paths of causation. QCA ignores the order of events by treating combinations of attributes as though they occur simultaneously rather than as unfolding over time. While preserving the essential strengths of QCA, the authorspresent a modification that is capable of capturing the temporal nature of causal interactions. This modification involves a hybrid of Boolean algebra and sequence analysis to create a parsimonious set of solutions. This technique is referred to as temporal qualitative comparative analysis, or TQCA.
Key Words: qualitative comparative analysis • comparative and historical methodology • time • temporality • sequence