As a first step towards applying ACT-R to problems of likelihood judgment, we draw parallels between ACT-R and HyGene. More specifically, in the spirit of theory integration, we demonstrate the relation between ACT-R's declarative memory system and the core of HyGene: Minerva2. We first start by transforming ACT-R's activation equations into what is in our view a more intuitive form. This form then allows us to more transparently see the correspondence between the effect of prior history and current context in the two theories. The results provide insights into the workings of the two theories and open an avenue for future attempts of theory integration, not only between the two theories, but also to related theories of memory. Moreover, we hope these results will be important steps toward testing ACT-R's capabilities of accounting for judgment phenomena.