Abstract: In the construction of a symmetric input-output table from supply-use tables it is necessary to invoke a technology assumption to disambiguate how an industry uses a given input in the production recipe of multiple outputs. We begin this talk by presenting a formulation which allows for the systematic exploration of technology assumptions, with a focus on hybrids between the commodity and industry technology assumptions. We then present a Bayesian method that describes how the practitioner's belief in a particular assumption evolves when confronted with empirical observations, when the state space of assumptions is either finite or continuous. We present preliminary results using Eurostat data and discuss the problem of how to handle empirical observations for which all assumptions perform poorly.